[PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Vivek Goyal]

Hi,

Here is another attempt on x86_64 relocatable bzImage patches(V4). This
patchset makes a bzImage relocatable and same kernel binary can be loaded
and run from different physical addresses.

As on now, this mainly helps distros who have to ship an extra kernel compiled
for a different physical address to capture the kernel crash dump. This
patchset will allow distros and kdump users to use production kernel itself
as dump capture kernel and there is no need to ship/build an extra kernel.
I am hopeful people will find other interesting usages down the line.

Eric has done all the heavy weight lifting requird to make this patchset
work. Last time I posted this patchset (V3), there were minor comments
which I have taken care of. Following are the changes since V3.

- Reduced the usage of _AC() macro to only shift operations, as per 
  Andi's comment.
- Restored the CONFIG_PHYSICAL_START option.
- Fixed few bugs with suspend to disk code path.

It would be good if these patches get into -mm so that it can undergo more
testing. I have been testing them and these just work fine for me.

Thanks
Vivek

[PATCH 1/20] x86_64: Assembly safe page.h and pgtable.h

[Vivek Goyal]

This patch makes pgtable.h and page.h safe to include
in assembly files like head.S.  Allowing us to use
symbolic constants instead of hard coded numbers when
refering to the page tables.

This patch copies asm-sparc64/const.h to asm-x86_64 to
get a definition of _AC() a very convinient macro that
allows us to force the type when we are compiling the
code in C and to drop all of the type information when
we are using the constant in assembly.  Previously this
was done with multiple definition of the same constant.
const.h was modified slightly so that it works when given
CONFIG options as arguments.

This patch adds #ifndef __ASSEMBLY__ ... #endif
and _AC(1,UL) where appropriate so the assembler won't
choke on the header files.  Otherwise nothing
should have changed.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 include/asm-x86_64/const.h   |   20 ++++++++++++++++++++
 include/asm-x86_64/page.h    |   28 ++++++++++------------------
 include/asm-x86_64/pgtable.h |   33 +++++++++++++++++++++------------
 3 files changed, 51 insertions(+), 30 deletions(-)

diff -puN /dev/null include/asm-x86_64/const.h
--- /dev/null	2007-03-07 00:46:17.354096448 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/const.h	2007-03-07 01:20:54.000000000 +0530
@@ -0,0 +1,20 @@
+/* const.h: Macros for dealing with constants.  */
+
+#ifndef _X86_64_CONST_H
+#define _X86_64_CONST_H
+
+/* Some constant macros are used in both assembler and
+ * C code.  Therefore we cannot annotate them always with
+ * 'UL' and other type specificers unilaterally.  We
+ * use the following macros to deal with this.
+ */
+
+#ifdef __ASSEMBLY__
+#define _AC(X,Y)	X
+#else
+#define __AC(X,Y)	(X##Y)
+#define _AC(X,Y)	__AC(X,Y)
+#endif
+
+
+#endif /* !(_X86_64_CONST_H) */
diff -puN include/asm-x86_64/page.h~x86_64-Assembly-safe-page.h-and-pgtable.h include/asm-x86_64/page.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/page.h~x86_64-Assembly-safe-page.h-and-pgtable.h	2007-03-07 01:20:54.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/page.h	2007-03-07 01:20:54.000000000 +0530
@@ -1,14 +1,11 @@
 #ifndef _X86_64_PAGE_H
 #define _X86_64_PAGE_H
 
+#include <asm/const.h>
 
 /* PAGE_SHIFT determines the page size */
 #define PAGE_SHIFT	12
-#ifdef __ASSEMBLY__
-#define PAGE_SIZE	(0x1 << PAGE_SHIFT)
-#else
-#define PAGE_SIZE	(1UL << PAGE_SHIFT)
-#endif
+#define PAGE_SIZE	(_AC(1,UL) << PAGE_SHIFT)
 #define PAGE_MASK	(~(PAGE_SIZE-1))
 #define PHYSICAL_PAGE_MASK	(~(PAGE_SIZE-1) & __PHYSICAL_MASK)
 
@@ -33,10 +30,10 @@
 #define N_EXCEPTION_STACKS 5  /* hw limit: 7 */
 
 #define LARGE_PAGE_MASK (~(LARGE_PAGE_SIZE-1))
-#define LARGE_PAGE_SIZE (1UL << PMD_SHIFT)
+#define LARGE_PAGE_SIZE (_AC(1,UL) << PMD_SHIFT)
 
 #define HPAGE_SHIFT PMD_SHIFT
-#define HPAGE_SIZE	((1UL) << HPAGE_SHIFT)
+#define HPAGE_SIZE	(_AC(1,UL) << HPAGE_SHIFT)
 #define HPAGE_MASK	(~(HPAGE_SIZE - 1))
 #define HUGETLB_PAGE_ORDER	(HPAGE_SHIFT - PAGE_SHIFT)
 
@@ -76,29 +73,24 @@ typedef struct { unsigned long pgprot; }
 #define __pgd(x) ((pgd_t) { (x) } )
 #define __pgprot(x)	((pgprot_t) { (x) } )
 
-#define __PHYSICAL_START	((unsigned long)CONFIG_PHYSICAL_START)
-#define __START_KERNEL		(__START_KERNEL_map + __PHYSICAL_START)
-#define __START_KERNEL_map	0xffffffff80000000UL
-#define __PAGE_OFFSET           0xffff810000000000UL
+#endif /* !__ASSEMBLY__ */
 
-#else
 #define __PHYSICAL_START	CONFIG_PHYSICAL_START
 #define __START_KERNEL		(__START_KERNEL_map + __PHYSICAL_START)
 #define __START_KERNEL_map	0xffffffff80000000
 #define __PAGE_OFFSET           0xffff810000000000
-#endif /* !__ASSEMBLY__ */
 
 /* to align the pointer to the (next) page boundary */
 #define PAGE_ALIGN(addr)	(((addr)+PAGE_SIZE-1)&PAGE_MASK)
 
 /* See Documentation/x86_64/mm.txt for a description of the memory map. */
 #define __PHYSICAL_MASK_SHIFT	46
-#define __PHYSICAL_MASK		((1UL << __PHYSICAL_MASK_SHIFT) - 1)
+#define __PHYSICAL_MASK		((_AC(1,UL) << __PHYSICAL_MASK_SHIFT) - 1)
 #define __VIRTUAL_MASK_SHIFT	48
-#define __VIRTUAL_MASK		((1UL << __VIRTUAL_MASK_SHIFT) - 1)
+#define __VIRTUAL_MASK		((_AC(1,UL) << __VIRTUAL_MASK_SHIFT) - 1)
 
-#define KERNEL_TEXT_SIZE  (40UL*1024*1024)
-#define KERNEL_TEXT_START 0xffffffff80000000UL 
+#define KERNEL_TEXT_SIZE  (40*1024*1024)
+#define KERNEL_TEXT_START 0xffffffff80000000
 
 #ifndef __ASSEMBLY__
 
@@ -106,7 +98,7 @@ typedef struct { unsigned long pgprot; }
 
 #endif /* __ASSEMBLY__ */
 
-#define PAGE_OFFSET		((unsigned long)__PAGE_OFFSET)
+#define PAGE_OFFSET		__PAGE_OFFSET
 
 /* Note: __pa(&symbol_visible_to_c) should be always replaced with __pa_symbol.
    Otherwise you risk miscompilation. */ 
diff -puN include/asm-x86_64/pgtable.h~x86_64-Assembly-safe-page.h-and-pgtable.h include/asm-x86_64/pgtable.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/pgtable.h~x86_64-Assembly-safe-page.h-and-pgtable.h	2007-03-07 01:20:54.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/pgtable.h	2007-03-07 01:20:54.000000000 +0530
@@ -1,6 +1,9 @@
 #ifndef _X86_64_PGTABLE_H
 #define _X86_64_PGTABLE_H
 
+#include <asm/const.h>
+#ifndef __ASSEMBLY__
+
 /*
  * This file contains the functions and defines necessary to modify and use
  * the x86-64 page table tree.
@@ -31,6 +34,8 @@ extern void clear_kernel_mapping(unsigne
 extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
 #define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
 
+#endif /* !__ASSEMBLY__ */
+
 /*
  * PGDIR_SHIFT determines what a top-level page table entry can map
  */
@@ -55,6 +60,8 @@ extern unsigned long empty_zero_page[PAG
  */
 #define PTRS_PER_PTE	512
 
+#ifndef __ASSEMBLY__
+
 #define pte_ERROR(e) \
 	printk("%s:%d: bad pte %p(%016lx).\n", __FILE__, __LINE__, &(e), pte_val(e))
 #define pmd_ERROR(e) \
@@ -118,22 +125,23 @@ static inline pte_t ptep_get_and_clear_f
 
 #define pte_pgprot(a)	(__pgprot((a).pte & ~PHYSICAL_PAGE_MASK))
 
-#define PMD_SIZE	(1UL << PMD_SHIFT)
+#endif /* !__ASSEMBLY__ */
+
+#define PMD_SIZE	(_AC(1,UL) << PMD_SHIFT)
 #define PMD_MASK	(~(PMD_SIZE-1))
-#define PUD_SIZE	(1UL << PUD_SHIFT)
+#define PUD_SIZE	(_AC(1,UL) << PUD_SHIFT)
 #define PUD_MASK	(~(PUD_SIZE-1))
-#define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
+#define PGDIR_SIZE	(_AC(1,UL) << PGDIR_SHIFT)
 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
 
 #define USER_PTRS_PER_PGD	((TASK_SIZE-1)/PGDIR_SIZE+1)
 #define FIRST_USER_ADDRESS	0
 
-#ifndef __ASSEMBLY__
-#define MAXMEM		 0x3fffffffffffUL
-#define VMALLOC_START    0xffffc20000000000UL
-#define VMALLOC_END      0xffffe1ffffffffffUL
-#define MODULES_VADDR    0xffffffff88000000UL
-#define MODULES_END      0xfffffffffff00000UL
+#define MAXMEM		 0x3fffffffffff
+#define VMALLOC_START    0xffffc20000000000
+#define VMALLOC_END      0xffffe1ffffffffff
+#define MODULES_VADDR    0xffffffff88000000
+#define MODULES_END      0xfffffffffff00000
 #define MODULES_LEN   (MODULES_END - MODULES_VADDR)
 
 #define _PAGE_BIT_PRESENT	0
@@ -159,7 +167,7 @@ static inline pte_t ptep_get_and_clear_f
 #define _PAGE_GLOBAL	0x100	/* Global TLB entry */
 
 #define _PAGE_PROTNONE	0x080	/* If not present */
-#define _PAGE_NX        (1UL<<_PAGE_BIT_NX)
+#define _PAGE_NX        (_AC(1,UL)<<_PAGE_BIT_NX)
 
 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
 #define _KERNPG_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
@@ -221,6 +229,8 @@ static inline pte_t ptep_get_and_clear_f
 #define __S110	PAGE_SHARED_EXEC
 #define __S111	PAGE_SHARED_EXEC
 
+#ifndef __ASSEMBLY__
+
 static inline unsigned long pgd_bad(pgd_t pgd)
 {
 	return pgd_val(pgd) & ~(PTE_MASK | _KERNPG_TABLE | _PAGE_USER);
@@ -406,8 +416,6 @@ extern spinlock_t pgd_lock;
 extern struct page *pgd_list;
 void vmalloc_sync_all(void);
 
-#endif /* !__ASSEMBLY__ */
-
 extern int kern_addr_valid(unsigned long addr); 
 
 #define io_remap_pfn_range(vma, vaddr, pfn, size, prot)		\
@@ -437,5 +445,6 @@ extern int kern_addr_valid(unsigned long
 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
 #define __HAVE_ARCH_PTE_SAME
 #include <asm-generic/pgtable.h>
+#endif /* !__ASSEMBLY__ */
 
 #endif /* _X86_64_PGTABLE_H */
_

Re: [PATCH 1/20] x86_64: Assembly safe page.h and pgtable.h

[Sam Ravnborg]

On Wed, Mar 07, 2007 at 12:29:20PM +0530, Vivek Goyal wrote:
> 
> 
> This patch makes pgtable.h and page.h safe to include
> in assembly files like head.S.  Allowing us to use
> symbolic constants instead of hard coded numbers when
> refering to the page tables.
> 
> This patch copies asm-sparc64/const.h to asm-x86_64 to
> get a definition of _AC() a very convinient macro that
> allows us to force the type when we are compiling the
> code in C and to drop all of the type information when
> we are using the constant in assembly.
Should this file not live in asm-generic and be useable
for all architectures?

	Sam

Re: [PATCH 1/20] x86_64: Assembly safe page.h and pgtable.h

[Vivek Goyal]

On Wed, Mar 07, 2007 at 08:24:04PM +0100, Sam Ravnborg wrote:
> On Wed, Mar 07, 2007 at 12:29:20PM +0530, Vivek Goyal wrote:
> > 
> > 
> > This patch makes pgtable.h and page.h safe to include
> > in assembly files like head.S.  Allowing us to use
> > symbolic constants instead of hard coded numbers when
> > refering to the page tables.
> > 
> > This patch copies asm-sparc64/const.h to asm-x86_64 to
> > get a definition of _AC() a very convinient macro that
> > allows us to force the type when we are compiling the
> > code in C and to drop all of the type information when
> > we are using the constant in assembly.
> Should this file not live in asm-generic and be useable
> for all architectures?
> 

Hi Sam,

Thanks for the review. This makes sense to me. Move const.h into
asm-generic and let everybody use it.

This is more of a small cleanup issue and involves changing few header files
in asm-sparc64 and make sure nothing is broken on sparc64. This patchset
is already becoming big and complex. Is it ok if we let the patch 
remain unmodified for now and once this gets in and settles down, I can
post another patch to do above modification?

Thanks
Vivek

Re: [PATCH 1/20] x86_64: Assembly safe page.h and pgtable.h

[Eric W. Biederman]

Vivek Goyal <vgoyal@in.ibm.com> writes:

> Hi Sam,
>
> Thanks for the review. This makes sense to me. Move const.h into
> asm-generic and let everybody use it.
>
> This is more of a small cleanup issue and involves changing few header files
> in asm-sparc64 and make sure nothing is broken on sparc64. This patchset
> is already becoming big and complex. Is it ok if we let the patch 
> remain unmodified for now and once this gets in and settles down, I can
> post another patch to do above modification?

Actually unless there is a reason not to, we can probably move this
into include/linux instead of include/asm-generic.  I don't see anything
in that header file that is architecture specific in any way.  Except
that it happens to only be used in architecture specific code.

Eric

[PATCH 2/20] x86_64: Kill temp boot pmds

[Vivek Goyal]

Early in the boot process we need the ability to set
up temporary mappings, before our normal mechanisms are
initialized.  Currently this is used to map pages that
are part of the page tables we are building and pages
during the dmi scan.

The core problem is that we are using the user portion of
the page tables to implement this.  Which means that while
this mechanism is active we cannot catch NULL pointer dereferences
and we deviate from the normal ways of handling things.

In this patch I modify early_ioremap to map pages into
the kernel portion of address space, roughly where
we will later put modules, and I make the discovery of
which addresses we can use dynamic which removes all
kinds of static limits and remove the dependencies
on implementation details between different parts of the code.

Now alloc_low_page() and unmap_low_page() use 
early_iomap() and early_iounmap() to allocate/map and 
unmap a page.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/head.S |    3 -
 arch/x86_64/mm/init.c     |  100 ++++++++++++++++++++--------------------------
 2 files changed, 45 insertions(+), 58 deletions(-)

diff -puN arch/x86_64/kernel/head.S~x86_64-Kill-temp_boot_pmds arch/x86_64/kernel/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head.S~x86_64-Kill-temp_boot_pmds	2007-03-07 01:21:26.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head.S	2007-03-07 01:21:26.000000000 +0530
@@ -288,9 +288,6 @@ NEXT_PAGE(level2_ident_pgt)
 	.quad	i << 21 | 0x083
 	i = i + 1
 	.endr
-	/* Temporary mappings for the super early allocator in arch/x86_64/mm/init.c */
-	.globl temp_boot_pmds
-temp_boot_pmds:
 	.fill	492,8,0
 	
 NEXT_PAGE(level2_kernel_pgt)
diff -puN arch/x86_64/mm/init.c~x86_64-Kill-temp_boot_pmds arch/x86_64/mm/init.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/mm/init.c~x86_64-Kill-temp_boot_pmds	2007-03-07 01:21:26.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/mm/init.c	2007-03-07 01:21:26.000000000 +0530
@@ -167,23 +167,9 @@ __set_fixmap (enum fixed_addresses idx, 
 
 unsigned long __initdata table_start, table_end; 
 
-extern pmd_t temp_boot_pmds[]; 
-
-static  struct temp_map { 
-	pmd_t *pmd;
-	void  *address; 
-	int    allocated; 
-} temp_mappings[] __initdata = { 
-	{ &temp_boot_pmds[0], (void *)(40UL * 1024 * 1024) },
-	{ &temp_boot_pmds[1], (void *)(42UL * 1024 * 1024) }, 
-	{}
-}; 
-
-static __meminit void *alloc_low_page(int *index, unsigned long *phys)
+static __meminit void *alloc_low_page(unsigned long *phys)
 { 
-	struct temp_map *ti;
-	int i; 
-	unsigned long pfn = table_end++, paddr; 
+	unsigned long pfn = table_end++;
 	void *adr;
 
 	if (after_bootmem) {
@@ -194,57 +180,63 @@ static __meminit void *alloc_low_page(in
 
 	if (pfn >= end_pfn) 
 		panic("alloc_low_page: ran out of memory"); 
-	for (i = 0; temp_mappings[i].allocated; i++) {
-		if (!temp_mappings[i].pmd) 
-			panic("alloc_low_page: ran out of temp mappings"); 
-	} 
-	ti = &temp_mappings[i];
-	paddr = (pfn << PAGE_SHIFT) & PMD_MASK; 
-	set_pmd(ti->pmd, __pmd(paddr | _KERNPG_TABLE | _PAGE_PSE)); 
-	ti->allocated = 1; 
-	__flush_tlb(); 	       
-	adr = ti->address + ((pfn << PAGE_SHIFT) & ~PMD_MASK); 
+
+	adr = early_ioremap(pfn * PAGE_SIZE, PAGE_SIZE);
 	memset(adr, 0, PAGE_SIZE);
-	*index = i; 
-	*phys  = pfn * PAGE_SIZE;  
-	return adr; 
-} 
+	*phys  = pfn * PAGE_SIZE;
+	return adr;
+}
 
-static __meminit void unmap_low_page(int i)
+static __meminit void unmap_low_page(void *adr)
 { 
-	struct temp_map *ti;
 
 	if (after_bootmem)
 		return;
 
-	ti = &temp_mappings[i];
-	set_pmd(ti->pmd, __pmd(0));
-	ti->allocated = 0; 
+	early_iounmap(adr, PAGE_SIZE);
 } 
 
 /* Must run before zap_low_mappings */
 __init void *early_ioremap(unsigned long addr, unsigned long size)
 {
-	unsigned long map = round_down(addr, LARGE_PAGE_SIZE); 
-
-	/* actually usually some more */
-	if (size >= LARGE_PAGE_SIZE) { 
-		return NULL;
+	unsigned long vaddr;
+	pmd_t *pmd, *last_pmd;
+	int i, pmds;
+
+	pmds = ((addr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE;
+	vaddr = __START_KERNEL_map;
+	pmd = level2_kernel_pgt;
+	last_pmd = level2_kernel_pgt + PTRS_PER_PMD - 1;
+	for (; pmd <= last_pmd; pmd++, vaddr += PMD_SIZE) {
+		for (i = 0; i < pmds; i++) {
+			if (pmd_present(pmd[i]))
+				goto next;
+		}
+		vaddr += addr & ~PMD_MASK;
+		addr &= PMD_MASK;
+		for (i = 0; i < pmds; i++, addr += PMD_SIZE)
+			set_pmd(pmd + i,__pmd(addr | _KERNPG_TABLE | _PAGE_PSE));
+		__flush_tlb();
+		return (void *)vaddr;
+	next:
+		;
 	}
-	set_pmd(temp_mappings[0].pmd,  __pmd(map | _KERNPG_TABLE | _PAGE_PSE));
-	map += LARGE_PAGE_SIZE;
-	set_pmd(temp_mappings[1].pmd,  __pmd(map | _KERNPG_TABLE | _PAGE_PSE));
-	__flush_tlb();
-	return temp_mappings[0].address + (addr & (LARGE_PAGE_SIZE-1));
+	printk("early_ioremap(0x%lx, %lu) failed\n", addr, size);
+	return NULL;
 }
 
 /* To avoid virtual aliases later */
 __init void early_iounmap(void *addr, unsigned long size)
 {
-	if ((void *)round_down((unsigned long)addr, LARGE_PAGE_SIZE) != temp_mappings[0].address)
-		printk("early_iounmap: bad address %p\n", addr);
-	set_pmd(temp_mappings[0].pmd, __pmd(0));
-	set_pmd(temp_mappings[1].pmd, __pmd(0));
+	unsigned long vaddr;
+	pmd_t *pmd;
+	int i, pmds;
+
+	vaddr = (unsigned long)addr;
+	pmds = ((vaddr & ~PMD_MASK) + size + ~PMD_MASK) / PMD_SIZE;
+	pmd = level2_kernel_pgt + pmd_index(vaddr);
+	for (i = 0; i < pmds; i++)
+		pmd_clear(pmd + i);
 	__flush_tlb();
 }
 
@@ -289,7 +281,6 @@ static void __meminit phys_pud_init(pud_
 
 
 	for (; i < PTRS_PER_PUD; i++, addr = (addr & PUD_MASK) + PUD_SIZE ) {
-		int map; 
 		unsigned long pmd_phys;
 		pud_t *pud = pud_page + pud_index(addr);
 		pmd_t *pmd;
@@ -307,12 +298,12 @@ static void __meminit phys_pud_init(pud_
 			continue;
 		}
 
-		pmd = alloc_low_page(&map, &pmd_phys);
+		pmd = alloc_low_page(&pmd_phys);
 		spin_lock(&init_mm.page_table_lock);
 		set_pud(pud, __pud(pmd_phys | _KERNPG_TABLE));
 		phys_pmd_init(pmd, addr, end);
 		spin_unlock(&init_mm.page_table_lock);
-		unmap_low_page(map);
+		unmap_low_page(pmd);
 	}
 	__flush_tlb();
 } 
@@ -364,7 +355,6 @@ void __meminit init_memory_mapping(unsig
 	end = (unsigned long)__va(end);
 
 	for (; start < end; start = next) {
-		int map;
 		unsigned long pud_phys; 
 		pgd_t *pgd = pgd_offset_k(start);
 		pud_t *pud;
@@ -372,7 +362,7 @@ void __meminit init_memory_mapping(unsig
 		if (after_bootmem)
 			pud = pud_offset(pgd, start & PGDIR_MASK);
 		else
-			pud = alloc_low_page(&map, &pud_phys);
+			pud = alloc_low_page(&pud_phys);
 
 		next = start + PGDIR_SIZE;
 		if (next > end) 
@@ -380,7 +370,7 @@ void __meminit init_memory_mapping(unsig
 		phys_pud_init(pud, __pa(start), __pa(next));
 		if (!after_bootmem)
 			set_pgd(pgd_offset_k(start), mk_kernel_pgd(pud_phys));
-		unmap_low_page(map);   
+		unmap_low_page(pud);
 	} 
 
 	if (!after_bootmem)
_

[PATCH 3/20] x86_64: Clean up the early boot page table

[Vivek Goyal]

- Merge physmem_pgt and ident_pgt, removing physmem_pgt.  The merge
  is broken as soon as mm/init.c:init_memory_mapping is run.
- As physmem_pgt is gone don't export it in pgtable.h.
- Use defines from pgtable.h for page permissions.
- Fix the physical memory identity mapping so it is at the correct
  address.
- Remove the physical memory mapping from wakeup_level4_pgt it
  is at the wrong address so we can't possibly be usinging it.
- Simply NEXT_PAGE the work to calculate the phys_ alias
  of the labels was very cool.  Unfortuantely it was a brittle
  special purpose hack that makes maitenance more difficult.
  Instead just use label - __START_KERNEL_map like we do
  everywhere else in assembly.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/head.S    |   61 +++++++++++++++++++------------------------
 include/asm-x86_64/pgtable.h |    1 
 2 files changed, 28 insertions(+), 34 deletions(-)

diff -puN arch/x86_64/kernel/head.S~x86_64-Cleanup-the-early-boot-page-table arch/x86_64/kernel/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head.S~x86_64-Cleanup-the-early-boot-page-table	2007-03-07 01:22:07.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head.S	2007-03-07 01:22:07.000000000 +0530
@@ -13,6 +13,7 @@
 #include <linux/init.h>
 #include <asm/desc.h>
 #include <asm/segment.h>
+#include <asm/pgtable.h>
 #include <asm/page.h>
 #include <asm/msr.h>
 #include <asm/cache.h>
@@ -260,52 +261,48 @@ ljumpvector:
 ENTRY(stext)
 ENTRY(_stext)
 
-	$page = 0
 #define NEXT_PAGE(name) \
-	$page = $page + 1; \
-	.org $page * 0x1000; \
-	phys_/**/name = $page * 0x1000 + __PHYSICAL_START; \
+	.balign	PAGE_SIZE; \
 ENTRY(name)
 
+/* Automate the creation of 1 to 1 mapping pmd entries */
+#define PMDS(START, PERM, COUNT)		\
+	i = 0 ;					\
+	.rept (COUNT) ;				\
+	.quad	(START) + (i << 21) + (PERM) ;	\
+	i = i + 1 ;				\
+	.endr
+
 NEXT_PAGE(init_level4_pgt)
 	/* This gets initialized in x86_64_start_kernel */
 	.fill	512,8,0
 
 NEXT_PAGE(level3_ident_pgt)
-	.quad	phys_level2_ident_pgt | 0x007
+	.quad	level2_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
 	.fill	511,8,0
 
 NEXT_PAGE(level3_kernel_pgt)
 	.fill	510,8,0
 	/* (2^48-(2*1024*1024*1024)-((2^39)*511))/(2^30) = 510 */
-	.quad	phys_level2_kernel_pgt | 0x007
+	.quad	level2_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
 	.fill	1,8,0
 
 NEXT_PAGE(level2_ident_pgt)
-	/* 40MB for bootup. 	*/
-	i = 0
-	.rept 20
-	.quad	i << 21 | 0x083
-	i = i + 1
-	.endr
-	.fill	492,8,0
+	/* Since I easily can, map the first 1G.
+	 * Don't set NX because code runs from these pages.
+	 */
+	PMDS(0x0000000000000000, __PAGE_KERNEL_LARGE_EXEC, PTRS_PER_PMD)
 	
 NEXT_PAGE(level2_kernel_pgt)
 	/* 40MB kernel mapping. The kernel code cannot be bigger than that.
 	   When you change this change KERNEL_TEXT_SIZE in page.h too. */
 	/* (2^48-(2*1024*1024*1024)-((2^39)*511)-((2^30)*510)) = 0 */
-	i = 0
-	.rept 20
-	.quad	i << 21 | 0x183
-	i = i + 1
-	.endr
+	PMDS(0x0000000000000000, __PAGE_KERNEL_LARGE_EXEC|_PAGE_GLOBAL,
+		KERNEL_TEXT_SIZE/PMD_SIZE)
 	/* Module mapping starts here */
-	.fill	492,8,0
-
-NEXT_PAGE(level3_physmem_pgt)
-	.quad	phys_level2_kernel_pgt | 0x007	/* so that __va works even before pagetable_init */
-	.fill	511,8,0
+	.fill	(PTRS_PER_PMD - (KERNEL_TEXT_SIZE/PMD_SIZE)),8,0
 
+#undef PMDS
 #undef NEXT_PAGE
 
 	.data
@@ -313,12 +310,10 @@ NEXT_PAGE(level3_physmem_pgt)
 #ifdef CONFIG_ACPI_SLEEP
 	.align PAGE_SIZE
 ENTRY(wakeup_level4_pgt)
-	.quad	phys_level3_ident_pgt | 0x007
-	.fill	255,8,0
-	.quad	phys_level3_physmem_pgt | 0x007
-	.fill	254,8,0
+	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.fill	510,8,0
 	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
-	.quad	phys_level3_kernel_pgt | 0x007
+	.quad	level3_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
 #endif
 
 #ifndef CONFIG_HOTPLUG_CPU
@@ -332,12 +327,12 @@ ENTRY(wakeup_level4_pgt)
 	 */
 	.align PAGE_SIZE
 ENTRY(boot_level4_pgt)
-	.quad	phys_level3_ident_pgt | 0x007
-	.fill	255,8,0
-	.quad	phys_level3_physmem_pgt | 0x007
-	.fill	254,8,0
+	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.fill	257,8,0
+	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.fill	252,8,0
 	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
-	.quad	phys_level3_kernel_pgt | 0x007
+	.quad	level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
 
 	.data
 
diff -puN include/asm-x86_64/pgtable.h~x86_64-Cleanup-the-early-boot-page-table include/asm-x86_64/pgtable.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/pgtable.h~x86_64-Cleanup-the-early-boot-page-table	2007-03-07 01:22:07.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/pgtable.h	2007-03-07 01:22:07.000000000 +0530
@@ -15,7 +15,6 @@
 #include <asm/pda.h>
 
 extern pud_t level3_kernel_pgt[512];
-extern pud_t level3_physmem_pgt[512];
 extern pud_t level3_ident_pgt[512];
 extern pmd_t level2_kernel_pgt[512];
 extern pgd_t init_level4_pgt[];
_

[PATCH 4/20] x86_64: Fix early printk to use standard ISA mapping

[Vivek Goyal]

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/early_printk.c |    3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff -puN arch/x86_64/kernel/early_printk.c~x86_64-fix-early_printk-to-use-the-standard-ISA-mapping arch/x86_64/kernel/early_printk.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/early_printk.c~x86_64-fix-early_printk-to-use-the-standard-ISA-mapping	2007-03-07 01:22:33.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/early_printk.c	2007-03-07 01:22:33.000000000 +0530
@@ -11,11 +11,10 @@
 
 #ifdef __i386__
 #include <asm/setup.h>
-#define VGABASE		(__ISA_IO_base + 0xb8000)
 #else
 #include <asm/bootsetup.h>
-#define VGABASE		((void __iomem *)0xffffffff800b8000UL)
 #endif
+#define VGABASE		(__ISA_IO_base + 0xb8000)
 
 static int max_ypos = 25, max_xpos = 80;
 static int current_ypos = 25, current_xpos = 0;
_

[PATCH 5/20] x86_64: modify copy_bootdata to use virtual addresses

[Vivek Goyal]

Use virtual addresses instead of physical addresses
in copy bootdata.  In addition fix the implementation
of the old bootloader convention.  Everything is
at real_mode_data always.  It is just that sometimes
real_mode_data was relocated by setup.S to not sit at
0x90000.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/head64.c |   17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff -puN arch/x86_64/kernel/head64.c~x86_64-modify-copy_bootdata-to-use-virtual-addresses arch/x86_64/kernel/head64.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head64.c~x86_64-modify-copy_bootdata-to-use-virtual-addresses	2007-03-07 01:23:55.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head64.c	2007-03-07 01:23:55.000000000 +0530
@@ -29,25 +29,24 @@ static void __init clear_bss(void)
 }
 
 #define NEW_CL_POINTER		0x228	/* Relative to real mode data */
-#define OLD_CL_MAGIC_ADDR	0x90020
+#define OLD_CL_MAGIC_ADDR	0x20
 #define OLD_CL_MAGIC            0xA33F
-#define OLD_CL_BASE_ADDR        0x90000
-#define OLD_CL_OFFSET           0x90022
+#define OLD_CL_OFFSET           0x22
 
 static void __init copy_bootdata(char *real_mode_data)
 {
-	int new_data;
+	unsigned long new_data;
 	char * command_line;
 
 	memcpy(x86_boot_params, real_mode_data, BOOT_PARAM_SIZE);
-	new_data = *(int *) (x86_boot_params + NEW_CL_POINTER);
+	new_data = *(u32 *) (x86_boot_params + NEW_CL_POINTER);
 	if (!new_data) {
-		if (OLD_CL_MAGIC != * (u16 *) OLD_CL_MAGIC_ADDR) {
+		if (OLD_CL_MAGIC != *(u16 *)(real_mode_data + OLD_CL_MAGIC_ADDR)) {
 			return;
 		}
-		new_data = OLD_CL_BASE_ADDR + * (u16 *) OLD_CL_OFFSET;
+		new_data = __pa(real_mode_data) + *(u16 *)(real_mode_data + OLD_CL_OFFSET);
 	}
-	command_line = (char *) ((u64)(new_data));
+	command_line = __va(new_data);
 	memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
 }
 
@@ -74,7 +73,7 @@ void __init x86_64_start_kernel(char * r
  		cpu_pda(i) = &boot_cpu_pda[i];
 
 	pda_init(0);
-	copy_bootdata(real_mode_data);
+	copy_bootdata(__va(real_mode_data));
 #ifdef CONFIG_SMP
 	cpu_set(0, cpu_online_map);
 #endif
_

[PATCH 6/20] x86_64: cleanup segments

[Vivek Goyal]

Move __KERNEL32_CS up into the unused gdt entry.  __KERNEL32_CS is
used when entering the kernel so putting it first is useful when
trying to keep boot gdt sizes to a minimum.

Set the accessed bit on all gdt entries.  We don't care
so there is no need for the cpu to burn the extra cycles,
and it potentially allows the pages to be immutable.  Plus
it is confusing when debugging and your gdt entries mysteriously
change.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/head.S    |   12 ++++++------
 include/asm-x86_64/segment.h |    2 +-
 2 files changed, 7 insertions(+), 7 deletions(-)

diff -puN arch/x86_64/kernel/head.S~x86_64-cleanup-segments arch/x86_64/kernel/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head.S~x86_64-cleanup-segments	2007-03-07 01:24:53.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head.S	2007-03-07 01:24:53.000000000 +0530
@@ -362,13 +362,13 @@ gdt:
 	
 ENTRY(cpu_gdt_table)
 	.quad	0x0000000000000000	/* NULL descriptor */
+	.quad	0x00cf9b000000ffff	/* __KERNEL32_CS */
+	.quad	0x00af9b000000ffff	/* __KERNEL_CS */
+	.quad	0x00cf93000000ffff	/* __KERNEL_DS */
+	.quad	0x00cffb000000ffff	/* __USER32_CS */
+	.quad	0x00cff3000000ffff	/* __USER_DS, __USER32_DS  */
+	.quad	0x00affb000000ffff	/* __USER_CS */
 	.quad	0x0			/* unused */
-	.quad	0x00af9a000000ffff	/* __KERNEL_CS */
-	.quad	0x00cf92000000ffff	/* __KERNEL_DS */
-	.quad	0x00cffa000000ffff	/* __USER32_CS */
-	.quad	0x00cff2000000ffff	/* __USER_DS, __USER32_DS  */		
-	.quad	0x00affa000000ffff	/* __USER_CS */
-	.quad	0x00cf9a000000ffff	/* __KERNEL32_CS */
 	.quad	0,0			/* TSS */
 	.quad	0,0			/* LDT */
 	.quad   0,0,0			/* three TLS descriptors */ 
diff -puN include/asm-x86_64/segment.h~x86_64-cleanup-segments include/asm-x86_64/segment.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/segment.h~x86_64-cleanup-segments	2007-03-07 01:24:53.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/segment.h	2007-03-07 01:24:53.000000000 +0530
@@ -6,7 +6,7 @@
 #define __KERNEL_CS	0x10
 #define __KERNEL_DS	0x18
 
-#define __KERNEL32_CS   0x38
+#define __KERNEL32_CS   0x08
 
 /* 
  * we cannot use the same code segment descriptor for user and kernel
_

[PATCH 7/20] x86_64: Add EFER to the register set saved by save_processor_state

[Vivek Goyal]

EFER varies like %cr4 depending on the cpu capabilities, and which cpu
capabilities we want to make use of.  So save/restore it make certain
we have the same EFER value when we are done.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/suspend.c |    3 ++-
 include/asm-x86_64/suspend.h |    1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff -puN arch/x86_64/kernel/suspend.c~x86_64-Add-EFER-to-the-set-registers-saved-by-save_processor_state arch/x86_64/kernel/suspend.c
--- linux-2.6.19-rc6-reloc/arch/x86_64/kernel/suspend.c~x86_64-Add-EFER-to-the-set-registers-saved-by-save_processor_state	2006-11-17 00:08:16.000000000 -0500
+++ linux-2.6.19-rc6-reloc-root/arch/x86_64/kernel/suspend.c	2006-11-17 00:08:16.000000000 -0500
@@ -33,7 +33,6 @@ void __save_processor_state(struct saved
 	asm volatile ("str %0"  : "=m" (ctxt->tr));
 
 	/* XMM0..XMM15 should be handled by kernel_fpu_begin(). */
-	/* EFER should be constant for kernel version, no need to handle it. */
 	/*
 	 * segment registers
 	 */
@@ -50,6 +49,7 @@ void __save_processor_state(struct saved
 	/*
 	 * control registers 
 	 */
+	rdmsrl(MSR_EFER, ctxt->efer);
 	asm volatile ("movq %%cr0, %0" : "=r" (ctxt->cr0));
 	asm volatile ("movq %%cr2, %0" : "=r" (ctxt->cr2));
 	asm volatile ("movq %%cr3, %0" : "=r" (ctxt->cr3));
@@ -75,6 +75,7 @@ void __restore_processor_state(struct sa
 	/*
 	 * control registers
 	 */
+	wrmsrl(MSR_EFER, ctxt->efer);
 	asm volatile ("movq %0, %%cr8" :: "r" (ctxt->cr8));
 	asm volatile ("movq %0, %%cr4" :: "r" (ctxt->cr4));
 	asm volatile ("movq %0, %%cr3" :: "r" (ctxt->cr3));
diff -puN include/asm-x86_64/suspend.h~x86_64-Add-EFER-to-the-set-registers-saved-by-save_processor_state include/asm-x86_64/suspend.h
--- linux-2.6.19-rc6-reloc/include/asm-x86_64/suspend.h~x86_64-Add-EFER-to-the-set-registers-saved-by-save_processor_state	2006-11-17 00:08:16.000000000 -0500
+++ linux-2.6.19-rc6-reloc-root/include/asm-x86_64/suspend.h	2006-11-17 00:08:16.000000000 -0500
@@ -17,6 +17,7 @@ struct saved_context {
   	u16 ds, es, fs, gs, ss;
 	unsigned long gs_base, gs_kernel_base, fs_base;
 	unsigned long cr0, cr2, cr3, cr4, cr8;
+	unsigned long efer;
 	u16 gdt_pad;
 	u16 gdt_limit;
 	unsigned long gdt_base;
_

[PATCH 8/20] x86_64: 64bit PIC SMP trampoline

[Vivek Goyal]

This modifies the SMP trampoline and all of the associated code so
it can jump to a 64bit kernel loaded at an arbitrary address.

The dependencies on having an idenetity mapped page in the kernel
page tables for SMP bootup have all been removed.

In addition the trampoline has been modified to verify
that long mode is supported.  Asking if long mode is implemented is
down right silly but we have traditionally had some of these checks,
and they can't hurt anything.  So when the totally ludicrous happens
we just might handle it correctly.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/head.S       |    1 
 arch/x86_64/kernel/setup.c      |    9 --
 arch/x86_64/kernel/trampoline.S |  168 ++++++++++++++++++++++++++++++++++++----
 3 files changed, 156 insertions(+), 22 deletions(-)

diff -puN arch/x86_64/kernel/head.S~x86_64-64bit-PIC-SMP-trampoline arch/x86_64/kernel/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head.S~x86_64-64bit-PIC-SMP-trampoline	2007-03-07 01:25:32.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head.S	2007-03-07 01:25:32.000000000 +0530
@@ -101,6 +101,7 @@ startup_32:
 	.org 0x100	
 	.globl startup_64
 startup_64:
+ENTRY(secondary_startup_64)
 	/* We come here either from startup_32
 	 * or directly from a 64bit bootloader.
 	 * Since we may have come directly from a bootloader we
diff -puN arch/x86_64/kernel/setup.c~x86_64-64bit-PIC-SMP-trampoline arch/x86_64/kernel/setup.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/setup.c~x86_64-64bit-PIC-SMP-trampoline	2007-03-07 01:25:32.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/setup.c	2007-03-07 01:25:32.000000000 +0530
@@ -329,15 +329,8 @@ void __init setup_arch(char **cmdline_p)
 #endif
 
 #ifdef CONFIG_SMP
-	/*
-	 * But first pinch a few for the stack/trampoline stuff
-	 * FIXME: Don't need the extra page at 4K, but need to fix
-	 * trampoline before removing it. (see the GDT stuff)
-	 */
-	reserve_bootmem_generic(PAGE_SIZE, PAGE_SIZE);
-
 	/* Reserve SMP trampoline */
-	reserve_bootmem_generic(SMP_TRAMPOLINE_BASE, PAGE_SIZE);
+	reserve_bootmem_generic(SMP_TRAMPOLINE_BASE, 2*PAGE_SIZE);
 #endif
 
 #ifdef CONFIG_ACPI_SLEEP
diff -puN arch/x86_64/kernel/trampoline.S~x86_64-64bit-PIC-SMP-trampoline arch/x86_64/kernel/trampoline.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/trampoline.S~x86_64-64bit-PIC-SMP-trampoline	2007-03-07 01:25:32.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/trampoline.S	2007-03-07 01:25:32.000000000 +0530
@@ -3,6 +3,7 @@
  *	Trampoline.S	Derived from Setup.S by Linus Torvalds
  *
  *	4 Jan 1997 Michael Chastain: changed to gnu as.
+ *	15 Sept 2005 Eric Biederman: 64bit PIC support
  *
  *	Entry: CS:IP point to the start of our code, we are 
  *	in real mode with no stack, but the rest of the 
@@ -17,15 +18,20 @@
  *	and IP is zero.  Thus, data addresses need to be absolute
  *	(no relocation) and are taken with regard to r_base.
  *
+ *	With the addition of trampoline_level4_pgt this code can
+ *	now enter a 64bit kernel that lives at arbitrary 64bit
+ *	physical addresses.
+ *
  *	If you work on this file, check the object module with objdump
  *	--full-contents --reloc to make sure there are no relocation
- *	entries. For the GDT entry we do hand relocation in smpboot.c
- *	because of 64bit linker limitations.
+ *	entries.
  */
 
 #include <linux/linkage.h>
-#include <asm/segment.h>
+#include <asm/pgtable.h>
 #include <asm/page.h>
+#include <asm/msr.h>
+#include <asm/segment.h>
 
 .data
 
@@ -33,15 +39,31 @@
 
 ENTRY(trampoline_data)
 r_base = .
+	cli			# We should be safe anyway
 	wbinvd	
 	mov	%cs, %ax	# Code and data in the same place
 	mov	%ax, %ds
+	mov	%ax, %es
+	mov	%ax, %ss
 
-	cli			# We should be safe anyway
 
 	movl	$0xA5A5A5A5, trampoline_data - r_base
 				# write marker for master knows we're running
 
+					# Setup stack
+	movw	$(trampoline_stack_end - r_base), %sp
+
+	call	verify_cpu		# Verify the cpu supports long mode
+
+	mov	%cs, %ax
+	movzx	%ax, %esi		# Find the 32bit trampoline location
+	shll	$4, %esi
+
+					# Fixup the vectors
+	addl	%esi, startup_32_vector - r_base
+	addl	%esi, startup_64_vector - r_base
+	addl	%esi, tgdt + 2 - r_base	# Fixup the gdt pointer
+
 	/*
 	 * GDT tables in non default location kernel can be beyond 16MB and
 	 * lgdt will not be able to load the address as in real mode default
@@ -49,23 +71,141 @@ r_base = .
 	 * to 32 bit.
 	 */
 
-	lidtl	idt_48 - r_base	# load idt with 0, 0
-	lgdtl	gdt_48 - r_base	# load gdt with whatever is appropriate
+	lidtl	tidt - r_base	# load idt with 0, 0
+	lgdtl	tgdt - r_base	# load gdt with whatever is appropriate
 
 	xor	%ax, %ax
 	inc	%ax		# protected mode (PE) bit
 	lmsw	%ax		# into protected mode
-	# flaush prefetch and jump to startup_32 in arch/x86_64/kernel/head.S
-	ljmpl	$__KERNEL32_CS, $(startup_32-__START_KERNEL_map)
+
+	# flush prefetch and jump to startup_32
+	ljmpl	*(startup_32_vector - r_base)
+
+	.code32
+	.balign 4
+startup_32:
+	movl	$__KERNEL_DS, %eax	# Initialize the %ds segment register
+	movl	%eax, %ds
+
+	xorl	%eax, %eax
+	btsl	$5, %eax		# Enable PAE mode
+	movl	%eax, %cr4
+
+					# Setup trampoline 4 level pagetables
+	leal	(trampoline_level4_pgt - r_base)(%esi), %eax
+	movl	%eax, %cr3
+
+	movl	$MSR_EFER, %ecx
+	movl	$(1 << _EFER_LME), %eax	# Enable Long Mode
+	xorl	%edx, %edx
+	wrmsr
+
+	xorl	%eax, %eax
+	btsl	$31, %eax		# Enable paging and in turn activate Long Mode
+	btsl	$0, %eax		# Enable protected mode
+	movl	%eax, %cr0
+
+	/*
+	 * At this point we're in long mode but in 32bit compatibility mode
+	 * with EFER.LME = 1, CS.L = 0, CS.D = 1 (and in turn
+	 * EFER.LMA = 1). Now we want to jump in 64bit mode, to do that we use
+	 * the new gdt/idt that has __KERNEL_CS with CS.L = 1.
+	 */
+	ljmp	*(startup_64_vector - r_base)(%esi)
+
+	.code64
+	.balign 4
+startup_64:
+	# Now jump into the kernel using virtual addresses
+	movq	$secondary_startup_64, %rax
+	jmp	*%rax
+
+	.code16
+verify_cpu:
+	pushl	$0			# Kill any dangerous flags
+	popfl
+
+	/* minimum CPUID flags for x86-64 */
+	/* see http://www.x86-64.org/lists/discuss/msg02971.html */
+#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\
+			   (1<<13)|(1<<15)|(1<<24)|(1<<25)|(1<<26))
+#define REQUIRED_MASK2 (1<<29)
+
+	pushfl				# check for cpuid
+	popl	%eax
+	movl	%eax, %ebx
+	xorl	$0x200000,%eax
+	pushl	%eax
+	popfl
+	pushfl
+	popl	%eax
+	pushl	%ebx
+	popfl
+	cmpl	%eax, %ebx
+	jz	no_longmode
+
+	xorl	%eax, %eax		# See if cpuid 1 is implemented
+	cpuid
+	cmpl	$0x1, %eax
+	jb	no_longmode
+
+	movl	$0x01, %eax		# Does the cpu have what it takes?
+	cpuid
+	andl	$REQUIRED_MASK1, %edx
+	xorl	$REQUIRED_MASK1, %edx
+	jnz	no_longmode
+
+	movl	$0x80000000, %eax	# See if extended cpuid is implemented
+	cpuid
+	cmpl	$0x80000001, %eax
+	jb	no_longmode
+
+	movl	$0x80000001, %eax	# Does the cpu have what it takes?
+	cpuid
+	andl	$REQUIRED_MASK2, %edx
+	xorl	$REQUIRED_MASK2, %edx
+	jnz	no_longmode
+
+	ret				# The cpu supports long mode
+
+no_longmode:
+	hlt
+	jmp no_longmode
+
 
 	# Careful these need to be in the same 64K segment as the above;
-idt_48:
+tidt:
 	.word	0			# idt limit = 0
 	.word	0, 0			# idt base = 0L
 
-gdt_48:
-	.short	GDT_ENTRIES*8 - 1	# gdt limit
-	.long	cpu_gdt_table-__START_KERNEL_map
+	# Duplicate the global descriptor table
+	# so the kernel can live anywhere
+	.balign 4
+tgdt:
+	.short	tgdt_end - tgdt		# gdt limit
+	.long	tgdt - r_base
+	.short 0
+	.quad	0x00cf9b000000ffff	# __KERNEL32_CS
+	.quad	0x00af9b000000ffff	# __KERNEL_CS
+	.quad	0x00cf93000000ffff	# __KERNEL_DS
+tgdt_end:
+
+	.balign 4
+startup_32_vector:
+	.long	startup_32 - r_base
+	.word	__KERNEL32_CS, 0
+
+	.balign 4
+startup_64_vector:
+	.long	startup_64 - r_base
+	.word	__KERNEL_CS, 0
+
+trampoline_stack:
+	.org 0x1000
+trampoline_stack_end:
+ENTRY(trampoline_level4_pgt)
+	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.fill	510,8,0
+	.quad	level3_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
 
-.globl trampoline_end
-trampoline_end:	
+ENTRY(trampoline_end)
_

[PATCH 9/20] x86_64: Get rid of dead code in suspend resume

[Vivek Goyal]

o Get rid of dead code in wakeup.S

o We never restore from saved_gdt, saved_idt, saved_ltd, saved_tss, saved_cr3,
  saved_cr4, saved_cr0, real_save_gdt, saved_efer, saved_efer2. Get rid
  of of associated code.

o Get rid of bogus_magic, bogus_31_magic and bogus_magic2. No longer being
  used.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/acpi/wakeup.S |   57 ---------------------------------------
 1 file changed, 1 insertion(+), 56 deletions(-)

diff -puN arch/x86_64/kernel/acpi/wakeup.S~x86_64-get-rid-of-dead-code-in-suspend-resume arch/x86_64/kernel/acpi/wakeup.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/acpi/wakeup.S~x86_64-get-rid-of-dead-code-in-suspend-resume	2007-03-07 01:26:21.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/acpi/wakeup.S	2007-03-07 01:26:21.000000000 +0530
@@ -258,8 +258,6 @@ gdt_48a:
 	.word	0, 0				# gdt base (filled in later)
 	
 	
-real_save_gdt:	.word 0
-		.quad 0
 real_magic:	.quad 0
 video_mode:	.quad 0
 video_flags:	.quad 0
@@ -272,10 +270,6 @@ bogus_32_magic:
 	movb	$0xb3,%al	;  outb %al,$0x80
 	jmp bogus_32_magic
 
-bogus_31_magic:
-	movb	$0xb1,%al	;  outb %al,$0x80
-	jmp bogus_31_magic
-
 bogus_cpu:
 	movb	$0xbc,%al	;  outb %al,$0x80
 	jmp bogus_cpu
@@ -346,16 +340,6 @@ check_vesaa:
 
 _setbada: jmp setbada
 
-	.code64
-bogus_magic:
-	movw	$0x0e00 + 'B', %ds:(0xb8018)
-	jmp bogus_magic
-
-bogus_magic2:
-	movw	$0x0e00 + '2', %ds:(0xb8018)
-	jmp bogus_magic2
-	
-
 wakeup_stack_begin:	# Stack grows down
 
 .org	0xff0
@@ -373,28 +357,11 @@ ENTRY(wakeup_end)
 #
 # Returned address is location of code in low memory (past data and stack)
 #
+	.code64
 ENTRY(acpi_copy_wakeup_routine)
 	pushq	%rax
-	pushq	%rcx
 	pushq	%rdx
 
-	sgdt	saved_gdt
-	sidt	saved_idt
-	sldt	saved_ldt
-	str	saved_tss
-
-	movq    %cr3, %rdx
-	movq    %rdx, saved_cr3
-	movq    %cr4, %rdx
-	movq    %rdx, saved_cr4
-	movq	%cr0, %rdx
-	movq	%rdx, saved_cr0
-	sgdt    real_save_gdt - wakeup_start (,%rdi)
-	movl	$MSR_EFER, %ecx
-	rdmsr
-	movl	%eax, saved_efer
-	movl	%edx, saved_efer2
-
 	movl	saved_video_mode, %edx
 	movl	%edx, video_mode - wakeup_start (,%rdi)
 	movl	acpi_video_flags, %edx
@@ -407,17 +374,8 @@ ENTRY(acpi_copy_wakeup_routine)
 	cmpl	$0x9abcdef0, %eax
 	jne	bogus_32_magic
 
-	# make sure %cr4 is set correctly (features, etc)
-	movl	saved_cr4 - __START_KERNEL_map, %eax
-	movq	%rax, %cr4
-
-	movl	saved_cr0 - __START_KERNEL_map, %eax
-	movq	%rax, %cr0
-	jmp	1f		# Flush pipelines
-1:
 	# restore the regs we used
 	popq	%rdx
-	popq	%rcx
 	popq	%rax
 ENTRY(do_suspend_lowlevel_s4bios)
 	ret
@@ -512,16 +470,3 @@ ENTRY(saved_eip)	.quad	0
 ENTRY(saved_esp)	.quad	0
 
 ENTRY(saved_magic)	.quad	0
-
-ALIGN
-# saved registers
-saved_gdt:	.quad	0,0
-saved_idt:	.quad	0,0
-saved_ldt:	.quad	0
-saved_tss:	.quad	0
-
-saved_cr0:	.quad 0
-saved_cr3:	.quad 0
-saved_cr4:	.quad 0
-saved_efer:	.quad 0
-saved_efer2:	.quad 0
_

[PATCH 10/20] x86_64: wakeup.S rename registers to reflect right names

[Vivek Goyal]

o Use appropriate names for 64bit regsiters.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/acpi/wakeup.S |   36 ++++++++++++++++++------------------
 include/asm-x86_64/suspend.h     |   12 ++++++------
 2 files changed, 24 insertions(+), 24 deletions(-)

diff -puN arch/x86_64/kernel/acpi/wakeup.S~x86_64-wakeup.S-rename-registers-to-reflect-right-names arch/x86_64/kernel/acpi/wakeup.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/acpi/wakeup.S~x86_64-wakeup.S-rename-registers-to-reflect-right-names	2007-03-07 01:26:55.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/acpi/wakeup.S	2007-03-07 01:26:55.000000000 +0530
@@ -211,16 +211,16 @@ wakeup_long64:
 	movw	%ax, %es
 	movw	%ax, %fs
 	movw	%ax, %gs
-	movq	saved_esp, %rsp
+	movq	saved_rsp, %rsp
 
 	movw	$0x0e00 + 'x', %ds:(0xb8018)
-	movq	saved_ebx, %rbx
-	movq	saved_edi, %rdi
-	movq	saved_esi, %rsi
-	movq	saved_ebp, %rbp
+	movq	saved_rbx, %rbx
+	movq	saved_rdi, %rdi
+	movq	saved_rsi, %rsi
+	movq	saved_rbp, %rbp
 
 	movw	$0x0e00 + '!', %ds:(0xb801a)
-	movq	saved_eip, %rax
+	movq	saved_rip, %rax
 	jmp	*%rax
 
 .code32
@@ -408,13 +408,13 @@ do_suspend_lowlevel:
 	movq %r15, saved_context_r15(%rip)
 	pushfq ; popq saved_context_eflags(%rip)
 
-	movq	$.L97, saved_eip(%rip)
+	movq	$.L97, saved_rip(%rip)
 
-	movq %rsp,saved_esp
-	movq %rbp,saved_ebp
-	movq %rbx,saved_ebx
-	movq %rdi,saved_edi
-	movq %rsi,saved_esi
+	movq %rsp,saved_rsp
+	movq %rbp,saved_rbp
+	movq %rbx,saved_rbx
+	movq %rdi,saved_rdi
+	movq %rsi,saved_rsi
 
 	addq	$8, %rsp
 	movl	$3, %edi
@@ -461,12 +461,12 @@ do_suspend_lowlevel:
 	
 .data
 ALIGN
-ENTRY(saved_ebp)	.quad	0
-ENTRY(saved_esi)	.quad	0
-ENTRY(saved_edi)	.quad	0
-ENTRY(saved_ebx)	.quad	0
+ENTRY(saved_rbp)	.quad	0
+ENTRY(saved_rsi)	.quad	0
+ENTRY(saved_rdi)	.quad	0
+ENTRY(saved_rbx)	.quad	0
 
-ENTRY(saved_eip)	.quad	0
-ENTRY(saved_esp)	.quad	0
+ENTRY(saved_rip)	.quad	0
+ENTRY(saved_rsp)	.quad	0
 
 ENTRY(saved_magic)	.quad	0
diff -puN include/asm-x86_64/suspend.h~x86_64-wakeup.S-rename-registers-to-reflect-right-names include/asm-x86_64/suspend.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/suspend.h~x86_64-wakeup.S-rename-registers-to-reflect-right-names	2007-03-07 01:26:55.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/suspend.h	2007-03-07 01:26:55.000000000 +0530
@@ -45,12 +45,12 @@ extern unsigned long saved_context_eflag
 extern void fix_processor_context(void);
 
 #ifdef CONFIG_ACPI_SLEEP
-extern unsigned long saved_eip;
-extern unsigned long saved_esp;
-extern unsigned long saved_ebp;
-extern unsigned long saved_ebx;
-extern unsigned long saved_esi;
-extern unsigned long saved_edi;
+extern unsigned long saved_rip;
+extern unsigned long saved_rsp;
+extern unsigned long saved_rbp;
+extern unsigned long saved_rbx;
+extern unsigned long saved_rsi;
+extern unsigned long saved_rdi;
 
 /* routines for saving/restoring kernel state */
 extern int acpi_save_state_mem(void);
_

Re: [PATCH 10/20] x86_64: wakeup.S rename registers to reflect right names

[Pavel Machek]

On Wed 2007-03-07 12:42:00, Vivek Goyal wrote:
> 
> 
> o Use appropriate names for 64bit regsiters.
> 
> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>

ACK.
								Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[PATCH 11/20] x86_64: wakeup.S misc cleanups

[Vivek Goyal]

o Various cleanups. One of the main purpose of cleanups is that make
  wakeup.S as close as possible to trampoline.S.

o Following are the changes
	- Indentations for comments.
	- Changed the gdt table to compact form and to resemble the
	  one in trampoline.S
	- Take the jump to 32bit from real mode using ljmpl. Makes code
	  more readable.
	- After enabling long mode, directly take a long jump for 64bit
	  mode. No need to take an extra jump to "reach_comaptibility_mode"
	- Stack is not used after real mode. So don't load stack in
 	  32 bit mode.
	- No need to enable PGE here.
	- No need to do extra EFER read, anyway we trash the read contents.
	- No need to enable system call (EFER_SCE). Anyway it will be 
	  enabled when original EFER is restored.
	- No need to set MP, ET, NE, WP, AM bits in cr0. Very soon we will
  	  reload the original cr0 while restroing the processor state.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/acpi/wakeup.S |  112 +++++++++++++--------------------------
 1 file changed, 40 insertions(+), 72 deletions(-)

diff -puN arch/x86_64/kernel/acpi/wakeup.S~x86_64-wakeup.S-misc-cleanups arch/x86_64/kernel/acpi/wakeup.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/acpi/wakeup.S~x86_64-wakeup.S-misc-cleanups	2007-03-07 01:27:32.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/acpi/wakeup.S	2007-03-07 01:27:32.000000000 +0530
@@ -30,11 +30,12 @@ wakeup_code:
 	cld
 	# setup data segment
 	movw	%cs, %ax
-	movw	%ax, %ds					# Make ds:0 point to wakeup_start
+	movw	%ax, %ds		# Make ds:0 point to wakeup_start
 	movw	%ax, %ss
-	mov	$(wakeup_stack - wakeup_code), %sp		# Private stack is needed for ASUS board
+					# Private stack is needed for ASUS board
+	mov	$(wakeup_stack - wakeup_code), %sp
 
-	pushl	$0						# Kill any dangerous flags
+	pushl	$0			# Kill any dangerous flags
 	popfl
 
 	movl	real_magic - wakeup_code, %eax
@@ -45,7 +46,7 @@ wakeup_code:
 	jz	1f
 	lcall   $0xc000,$3
 	movw	%cs, %ax
-	movw	%ax, %ds					# Bios might have played with that
+	movw	%ax, %ds		# Bios might have played with that
 	movw	%ax, %ss
 1:
 
@@ -75,9 +76,12 @@ wakeup_code:
 	jmp	1f
 1:
 
-	.byte 0x66, 0xea			# prefix + jmpi-opcode
-	.long	wakeup_32 - __START_KERNEL_map
-	.word	__KERNEL_CS
+	ljmpl   *(wakeup_32_vector - wakeup_code)
+
+	.balign 4
+wakeup_32_vector:
+	.long   wakeup_32 - __START_KERNEL_map
+	.word   __KERNEL32_CS, 0
 
 	.code32
 wakeup_32:
@@ -96,65 +100,50 @@ wakeup_32:
 	jnc	bogus_cpu
 	movl	%edx,%edi
 	
-	movw	$__KERNEL_DS, %ax
-	movw	%ax, %ds
-	movw	%ax, %es
-	movw	%ax, %fs
-	movw	%ax, %gs
+	movl	$__KERNEL_DS, %eax
+	movl	%eax, %ds
 
-	movw	$__KERNEL_DS, %ax	
-	movw	%ax, %ss
-
-	mov	$(wakeup_stack - __START_KERNEL_map), %esp
 	movl	saved_magic - __START_KERNEL_map, %eax
 	cmpl	$0x9abcdef0, %eax
 	jne	bogus_32_magic
 
+	movw	$0x0e00 + 'i', %ds:(0xb8012)
+	movb	$0xa8, %al	;  outb %al, $0x80;
+
 	/*
 	 * Prepare for entering 64bits mode
 	 */
 
-	/* Enable PAE mode and PGE */
+	/* Enable PAE */
 	xorl	%eax, %eax
 	btsl	$5, %eax
-	btsl	$7, %eax
 	movl	%eax, %cr4
 
 	/* Setup early boot stage 4 level pagetables */
 	movl	$(wakeup_level4_pgt - __START_KERNEL_map), %eax
 	movl	%eax, %cr3
 
-	/* Setup EFER (Extended Feature Enable Register) */
-	movl	$MSR_EFER, %ecx
-	rdmsr
-	/* Fool rdmsr and reset %eax to avoid dependences */
-	xorl	%eax, %eax
 	/* Enable Long Mode */
+	xorl    %eax, %eax
 	btsl	$_EFER_LME, %eax
-	/* Enable System Call */
-	btsl	$_EFER_SCE, %eax
 
-	/* No Execute supported? */	
+	/* No Execute supported? */
 	btl	$20,%edi
 	jnc     1f
 	btsl	$_EFER_NX, %eax
-1:	
 				
 	/* Make changes effective */
+1:	movl    $MSR_EFER, %ecx
+	xorl    %edx, %edx
 	wrmsr
-	wbinvd
 
 	xorl	%eax, %eax
 	btsl	$31, %eax			/* Enable paging and in turn activate Long Mode */
 	btsl	$0, %eax			/* Enable protected mode */
-	btsl	$1, %eax			/* Enable MP */
-	btsl	$4, %eax			/* Enable ET */
-	btsl	$5, %eax			/* Enable NE */
-	btsl	$16, %eax			/* Enable WP */
-	btsl	$18, %eax			/* Enable AM */
 
 	/* Make changes effective */
 	movl	%eax, %cr0
+
 	/* At this point:
 		CR4.PAE must be 1
 		CS.L must be 0
@@ -162,11 +151,6 @@ wakeup_32:
 		Next instruction must be a branch
 		This must be on identity-mapped page
 	*/
-	jmp	reach_compatibility_mode
-reach_compatibility_mode:
-	movw	$0x0e00 + 'i', %ds:(0xb8012)
-	movb	$0xa8, %al	;  outb %al, $0x80; 	
-		
 	/*
 	 * At this point we're in long mode but in 32bit compatibility mode
 	 * with EFER.LME = 1, CS.L = 0, CS.D = 1 (and in turn
@@ -174,24 +158,19 @@ reach_compatibility_mode:
 	 * the new gdt/idt that has __KERNEL_CS with CS.L = 1.
 	 */
 
-	movw	$0x0e00 + 'n', %ds:(0xb8014)
-	movb	$0xa9, %al	;  outb %al, $0x80
-	
-	/* Load new GDT with the 64bit segment using 32bit descriptor */
-	movl	$(pGDT32 - __START_KERNEL_map), %eax
-	lgdt	(%eax)
-
-	movl    $(wakeup_jumpvector - __START_KERNEL_map), %eax
 	/* Finally jump in 64bit mode */
-	ljmp	*(%eax)
+	ljmp	*(wakeup_long64_vector - __START_KERNEL_map)
 
-wakeup_jumpvector:
-	.long	wakeup_long64 - __START_KERNEL_map
-	.word	__KERNEL_CS
+	.balign 4
+wakeup_long64_vector:
+	.long   wakeup_long64 - __START_KERNEL_map
+	.word   __KERNEL_CS, 0
 
 .code64
 
-	/*	Hooray, we are in Long 64-bit mode (but still running in low memory) */
+	/* Hooray, we are in Long 64-bit mode (but still running in
+	 * low memory)
+	 */
 wakeup_long64:
 	/*
 	 * We must switch to a new descriptor in kernel space for the GDT
@@ -201,6 +180,9 @@ wakeup_long64:
 	 */
 	lgdt	cpu_gdt_descr - __START_KERNEL_map
 
+	movw	$0x0e00 + 'n', %ds:(0xb8014)
+	movb	$0xa9, %al	;  outb %al, $0x80
+
 	movw	$0x0e00 + 'u', %ds:(0xb8016)
 	
 	nop
@@ -227,33 +209,19 @@ wakeup_long64:
 
 	.align	64	
 gdta:
+	/* Its good to keep gdt in sync with one in trampoline.S */
 	.word	0, 0, 0, 0			# dummy
-
-	.word	0, 0, 0, 0			# unused
-
-	.word	0xFFFF				# 4Gb - (0x100000*0x1000 = 4Gb)
-	.word	0				# base address = 0
-	.word	0x9B00				# code read/exec. ??? Why I need 0x9B00 (as opposed to 0x9A00 in order for this to work?)
-	.word	0x00CF				# granularity = 4096, 386
-						#  (+5th nibble of limit)
-
-	.word	0xFFFF				# 4Gb - (0x100000*0x1000 = 4Gb)
-	.word	0				# base address = 0
-	.word	0x9200				# data read/write
-	.word	0x00CF				# granularity = 4096, 386
-						#  (+5th nibble of limit)
-# this is 64bit descriptor for code
-	.word	0xFFFF
-	.word	0
-	.word	0x9A00				# code read/exec
-	.word	0x00AF				# as above, but it is long mode and with D=0
+	/* ??? Why I need the accessed bit set in order for this to work? */
+	.quad   0x00cf9b000000ffff              # __KERNEL32_CS
+	.quad   0x00af9b000000ffff              # __KERNEL_CS
+	.quad   0x00cf93000000ffff              # __KERNEL_DS
 
 idt_48a:
 	.word	0				# idt limit = 0
 	.word	0, 0				# idt base = 0L
 
 gdt_48a:
-	.word	0x8000				# gdt limit=2048,
+	.word	0x800				# gdt limit=2048,
 						#  256 GDT entries
 	.word	0, 0				# gdt base (filled in later)
 	
@@ -263,7 +231,7 @@ video_mode:	.quad 0
 video_flags:	.quad 0
 
 bogus_real_magic:
-	movb	$0xba,%al	;  outb %al,$0x80		
+	movb	$0xba,%al	;  outb %al,$0x80
 	jmp bogus_real_magic
 
 bogus_32_magic:
_

Re: [PATCH 11/20] x86_64: wakeup.S misc cleanups

[Pavel Machek]

Hi!

> o Various cleanups. One of the main purpose of cleanups is that make
>   wakeup.S as close as possible to trampoline.S.
> 
> o Following are the changes
> 	- Indentations for comments.
> 	- Changed the gdt table to compact form and to resemble the
> 	  one in trampoline.S
> 	- Take the jump to 32bit from real mode using ljmpl. Makes code
> 	  more readable.
> 	- After enabling long mode, directly take a long jump for 64bit
> 	  mode. No need to take an extra jump to "reach_comaptibility_mode"
> 	- Stack is not used after real mode. So don't load stack in
>  	  32 bit mode.
> 	- No need to enable PGE here.
> 	- No need to do extra EFER read, anyway we trash the read contents.
> 	- No need to enable system call (EFER_SCE). Anyway it will be 
> 	  enabled when original EFER is restored.
> 	- No need to set MP, ET, NE, WP, AM bits in cr0. Very soon we will
>   	  reload the original cr0 while restroing the processor state.
> 
> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>

ACK, provided it was tested.
									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH 11/20] x86_64: wakeup.S misc cleanups

[Vivek Goyal]

On Wed, Mar 07, 2007 at 11:40:53PM +0100, Pavel Machek wrote:
> Hi!
> 
> > o Various cleanups. One of the main purpose of cleanups is that make
> >   wakeup.S as close as possible to trampoline.S.
> > 
> > o Following are the changes
> > 	- Indentations for comments.
> > 	- Changed the gdt table to compact form and to resemble the
> > 	  one in trampoline.S
> > 	- Take the jump to 32bit from real mode using ljmpl. Makes code
> > 	  more readable.
> > 	- After enabling long mode, directly take a long jump for 64bit
> > 	  mode. No need to take an extra jump to "reach_comaptibility_mode"
> > 	- Stack is not used after real mode. So don't load stack in
> >  	  32 bit mode.
> > 	- No need to enable PGE here.
> > 	- No need to do extra EFER read, anyway we trash the read contents.
> > 	- No need to enable system call (EFER_SCE). Anyway it will be 
> > 	  enabled when original EFER is restored.
> > 	- No need to set MP, ET, NE, WP, AM bits in cr0. Very soon we will
> >   	  reload the original cr0 while restroing the processor state.
> > 
> > Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
> > Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
> 
> ACK, provided it was tested.
> 									Pavel

Hi Pavel,

Thanks. I tested all the S3 related changes during my last posting. That
time I had access to an x86_64 box which supported ACPI state S3. Since then
this code has not changed and it has been running successfully in RHEL5 
kernels. Now I don't have access to an x86_64 machine which supports S3
so I can't test suspend to RAM. But I am sure that these patches are working
as nothing has changed since last posting.

Just now Nigel reported successful suspend to RAM results for 2.6.20. I
have requested him to test it for 2.6.21-rc2 also, if possible.

I have throughly tested suspend to disk (S4) and it works fine.

Thanks
Vivek

Re: [PATCH 11/20] x86_64: wakeup.S misc cleanups

[Pavel Machek]

Hi!

> +	movw	$0x0e00 + 'i', %ds:(0xb8012)
> +	movb	$0xa8, %al	;  outb %al, $0x80;
> +

> -	movw	$0x0e00 + 'i', %ds:(0xb8012)
> -	movb	$0xa8, %al	;  outb %al, $0x80; 	

Outbs were my debugging hacks, perhaps you can simply remove them at
this point? Not sure how useful "Linux" debug print is, it can
probably be removed, too.


-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH 11/20] x86_64: wakeup.S misc cleanups

[Vivek Goyal]

On Wed, Mar 07, 2007 at 11:41:57PM +0100, Pavel Machek wrote:
> Hi!
> 
> > +	movw	$0x0e00 + 'i', %ds:(0xb8012)
> > +	movb	$0xa8, %al	;  outb %al, $0x80;
> > +
> 
> > -	movw	$0x0e00 + 'i', %ds:(0xb8012)
> > -	movb	$0xa8, %al	;  outb %al, $0x80; 	
> 
> Outbs were my debugging hacks, perhaps you can simply remove them at
> this point? Not sure how useful "Linux" debug print is, it can
> probably be removed, too.
> 

Hi Pavel,

I found these debugging hacks useful while debugging some problem with 
my changes in this code. It helps to find out till what poing code flow
as reached in this assembly code. So I think its not a bad idea to let
this piece code be there.

Thanks
Vivek

Re: [PATCH 11/20] x86_64: wakeup.S misc cleanups

[Pavel Machek]

Hi!

> > > +	movw	$0x0e00 + 'i', %ds:(0xb8012)
> > > +	movb	$0xa8, %al	;  outb %al, $0x80;
> > > +
> > 
> > > -	movw	$0x0e00 + 'i', %ds:(0xb8012)
> > > -	movb	$0xa8, %al	;  outb %al, $0x80; 	
> > 
> > Outbs were my debugging hacks, perhaps you can simply remove them at
> > this point? Not sure how useful "Linux" debug print is, it can
> > probably be removed, too.
> > 
> 
> Hi Pavel,
> 
> I found these debugging hacks useful while debugging some problem with 
> my changes in this code. It helps to find out till what poing code flow
> as reached in this assembly code. So I think its not a bad idea to let
> this piece code be there.

Ok. (I was not sure how common are displays of port 0x80).


-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [Fastboot] [PATCH 11/20] x86_64: wakeup.S misc cleanups

[Lombard, David N]

On Thu, Mar 08, 2007 at 12:43:35PM +0100, Pavel Machek wrote:
> > > > +	movw	$0x0e00 + 'i', %ds:(0xb8012)
> > > > +	movb	$0xa8, %al	;  outb %al, $0x80;
> > > > +
> > > 
> > > > -	movw	$0x0e00 + 'i', %ds:(0xb8012)
> > > > -	movb	$0xa8, %al	;  outb %al, $0x80; 	
> > > 
> > > Outbs were my debugging hacks, perhaps you can simply remove them at
> > > this point? Not sure how useful "Linux" debug print is, it can
> > > probably be removed, too.
> > > 
> > I found these debugging hacks useful while debugging some problem with 
> > my changes in this code. It helps to find out till what poing code flow
> > as reached in this assembly code. So I think its not a bad idea to let
> > this piece code be there.
> 
> Ok. (I was not sure how common are displays of port 0x80).

They're now typically available in reasonably well stocked stores; I picked
one up from CompUSA about a year ago...

-- 
David N. Lombard, Intel, Irvine, CA
I do not speak for Intel Corporation; all comments are strictly my own.

[PATCH 12/20] x86_64: 64bit ACPI wakeup trampoline

[Vivek Goyal]

o Moved wakeup_level4_pgt into the wakeup routine so we can
  run the kernel above 4G.

o Now we first go to 64bit mode and continue to run from trampoline and
  then then start accessing kernel symbols and restore processor context.
  This enables us to resume even in relocatable kernel context when 
  kernel might not be loaded at physical addr it has been compiled for.

o Removed the need for modifying any existing kernel page table.

o Increased the size of the wakeup routine to 8K. This is required as
  wake page tables are on trampoline itself and they got to be at 4K
  boundary, hence one page is not sufficient.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/acpi/sleep.c  |   22 ++------------
 arch/x86_64/kernel/acpi/wakeup.S |   59 ++++++++++++++++++++++++---------------
 arch/x86_64/kernel/head.S        |    9 -----
 3 files changed, 41 insertions(+), 49 deletions(-)

diff -puN arch/x86_64/kernel/acpi/sleep.c~x86_64-64bit-ACPI-wakeup-trampoline arch/x86_64/kernel/acpi/sleep.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/acpi/sleep.c~x86_64-64bit-ACPI-wakeup-trampoline	2007-03-07 01:28:11.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/acpi/sleep.c	2007-03-07 01:28:11.000000000 +0530
@@ -60,17 +60,6 @@ extern char wakeup_start, wakeup_end;
 
 extern unsigned long acpi_copy_wakeup_routine(unsigned long);
 
-static pgd_t low_ptr;
-
-static void init_low_mapping(void)
-{
-	pgd_t *slot0 = pgd_offset(current->mm, 0UL);
-	low_ptr = *slot0;
-	set_pgd(slot0, *pgd_offset(current->mm, PAGE_OFFSET));
-	WARN_ON(num_online_cpus() != 1);
-	local_flush_tlb();
-}
-
 /**
  * acpi_save_state_mem - save kernel state
  *
@@ -79,8 +68,6 @@ static void init_low_mapping(void)
  */
 int acpi_save_state_mem(void)
 {
-	init_low_mapping();
-
 	memcpy((void *)acpi_wakeup_address, &wakeup_start,
 	       &wakeup_end - &wakeup_start);
 	acpi_copy_wakeup_routine(acpi_wakeup_address);
@@ -93,8 +80,6 @@ int acpi_save_state_mem(void)
  */
 void acpi_restore_state_mem(void)
 {
-	set_pgd(pgd_offset(current->mm, 0UL), low_ptr);
-	local_flush_tlb();
 }
 
 /**
@@ -107,10 +92,11 @@ void acpi_restore_state_mem(void)
  */
 void __init acpi_reserve_bootmem(void)
 {
-	acpi_wakeup_address = (unsigned long)alloc_bootmem_low(PAGE_SIZE);
-	if ((&wakeup_end - &wakeup_start) > PAGE_SIZE)
+	acpi_wakeup_address = (unsigned long)alloc_bootmem_low(PAGE_SIZE*2);
+	if ((&wakeup_end - &wakeup_start) > (PAGE_SIZE*2))
 		printk(KERN_CRIT
-		       "ACPI: Wakeup code way too big, will crash on attempt to suspend\n");
+		       "ACPI: Wakeup code way too big, will crash on attempt"
+		       " to suspend\n");
 }
 
 static int __init acpi_sleep_setup(char *str)
diff -puN arch/x86_64/kernel/acpi/wakeup.S~x86_64-64bit-ACPI-wakeup-trampoline arch/x86_64/kernel/acpi/wakeup.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/acpi/wakeup.S~x86_64-64bit-ACPI-wakeup-trampoline	2007-03-07 01:28:11.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/acpi/wakeup.S	2007-03-07 01:28:11.000000000 +0530
@@ -1,6 +1,7 @@
 .text
 #include <linux/linkage.h>
 #include <asm/segment.h>
+#include <asm/pgtable.h>
 #include <asm/page.h>
 #include <asm/msr.h>
 
@@ -62,12 +63,15 @@ wakeup_code:
 
 	movb	$0xa2, %al	;  outb %al, $0x80
 	
-	lidt	%ds:idt_48a - wakeup_code
-	xorl	%eax, %eax
-	movw	%ds, %ax			# (Convert %ds:gdt to a linear ptr)
-	shll	$4, %eax
-	addl	$(gdta - wakeup_code), %eax
-	movl	%eax, gdt_48a +2 - wakeup_code
+	mov	%ds, %ax			# Find 32bit wakeup_code addr
+	movzx   %ax, %esi			# (Convert %ds:gdt to a liner ptr)
+	shll    $4, %esi
+						# Fix up the vectors
+	addl    %esi, wakeup_32_vector - wakeup_code
+	addl    %esi, wakeup_long64_vector - wakeup_code
+	addl    %esi, gdt_48a + 2 - wakeup_code # Fixup the gdt pointer
+
+	lidtl	%ds:idt_48a - wakeup_code
 	lgdtl	%ds:gdt_48a - wakeup_code	# load gdt with whatever is
 						# appropriate
 
@@ -80,7 +84,7 @@ wakeup_code:
 
 	.balign 4
 wakeup_32_vector:
-	.long   wakeup_32 - __START_KERNEL_map
+	.long   wakeup_32 - wakeup_code
 	.word   __KERNEL32_CS, 0
 
 	.code32
@@ -103,10 +107,6 @@ wakeup_32:
 	movl	$__KERNEL_DS, %eax
 	movl	%eax, %ds
 
-	movl	saved_magic - __START_KERNEL_map, %eax
-	cmpl	$0x9abcdef0, %eax
-	jne	bogus_32_magic
-
 	movw	$0x0e00 + 'i', %ds:(0xb8012)
 	movb	$0xa8, %al	;  outb %al, $0x80;
 
@@ -120,7 +120,7 @@ wakeup_32:
 	movl	%eax, %cr4
 
 	/* Setup early boot stage 4 level pagetables */
-	movl	$(wakeup_level4_pgt - __START_KERNEL_map), %eax
+	leal    (wakeup_level4_pgt - wakeup_code)(%esi), %eax
 	movl	%eax, %cr3
 
 	/* Enable Long Mode */
@@ -159,11 +159,11 @@ wakeup_32:
 	 */
 
 	/* Finally jump in 64bit mode */
-	ljmp	*(wakeup_long64_vector - __START_KERNEL_map)
+        ljmp    *(wakeup_long64_vector - wakeup_code)(%esi)
 
 	.balign 4
 wakeup_long64_vector:
-	.long   wakeup_long64 - __START_KERNEL_map
+	.long   wakeup_long64 - wakeup_code
 	.word   __KERNEL_CS, 0
 
 .code64
@@ -178,11 +178,16 @@ wakeup_long64:
 	 * addresses where we're currently running on. We have to do that here
 	 * because in 32bit we couldn't load a 64bit linear address.
 	 */
-	lgdt	cpu_gdt_descr - __START_KERNEL_map
+	lgdt	cpu_gdt_descr
 
 	movw	$0x0e00 + 'n', %ds:(0xb8014)
 	movb	$0xa9, %al	;  outb %al, $0x80
 
+	movq    saved_magic, %rax
+	movq    $0x123456789abcdef0, %rdx
+	cmpq    %rdx, %rax
+	jne     bogus_64_magic
+
 	movw	$0x0e00 + 'u', %ds:(0xb8016)
 	
 	nop
@@ -223,20 +228,21 @@ idt_48a:
 gdt_48a:
 	.word	0x800				# gdt limit=2048,
 						#  256 GDT entries
-	.word	0, 0				# gdt base (filled in later)
-	
+	.long   gdta - wakeup_code              # gdt base (relocated in later)
 	
 real_magic:	.quad 0
 video_mode:	.quad 0
 video_flags:	.quad 0
 
+.code16
 bogus_real_magic:
 	movb	$0xba,%al	;  outb %al,$0x80
 	jmp bogus_real_magic
 
-bogus_32_magic:
+.code64
+bogus_64_magic:
 	movb	$0xb3,%al	;  outb %al,$0x80
-	jmp bogus_32_magic
+	jmp bogus_64_magic
 
 bogus_cpu:
 	movb	$0xbc,%al	;  outb %al,$0x80
@@ -263,6 +269,7 @@ bogus_cpu:
 #define VIDEO_FIRST_V7 0x0900
 
 # Setting of user mode (AX=mode ID) => CF=success
+.code16
 mode_seta:
 	movw	%ax, %bx
 #if 0
@@ -313,6 +320,13 @@ wakeup_stack_begin:	# Stack grows down
 .org	0xff0
 wakeup_stack:		# Just below end of page
 
+.org   0x1000
+ENTRY(wakeup_level4_pgt)
+	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.fill   510,8,0
+	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
+	.quad   level3_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
+
 ENTRY(wakeup_end)
 	
 ##
@@ -338,9 +352,10 @@ ENTRY(acpi_copy_wakeup_routine)
 	movq	$0x123456789abcdef0, %rdx
 	movq	%rdx, saved_magic
 
-	movl	saved_magic - __START_KERNEL_map, %eax
-	cmpl	$0x9abcdef0, %eax
-	jne	bogus_32_magic
+	movq    saved_magic, %rax
+	movq    $0x123456789abcdef0, %rdx
+	cmpq    %rdx, %rax
+	jne     bogus_64_magic
 
 	# restore the regs we used
 	popq	%rdx
diff -puN arch/x86_64/kernel/head.S~x86_64-64bit-ACPI-wakeup-trampoline arch/x86_64/kernel/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head.S~x86_64-64bit-ACPI-wakeup-trampoline	2007-03-07 01:28:11.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head.S	2007-03-07 01:28:11.000000000 +0530
@@ -308,15 +308,6 @@ NEXT_PAGE(level2_kernel_pgt)
 
 	.data
 
-#ifdef CONFIG_ACPI_SLEEP
-	.align PAGE_SIZE
-ENTRY(wakeup_level4_pgt)
-	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.fill	510,8,0
-	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
-	.quad	level3_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
-#endif
-
 #ifndef CONFIG_HOTPLUG_CPU
 	__INITDATA
 #endif
_

Re: [PATCH 12/20] x86_64: 64bit ACPI wakeup trampoline

[Pavel Machek]

Hi!

> o Moved wakeup_level4_pgt into the wakeup routine so we can
>   run the kernel above 4G.
> 
> o Now we first go to 64bit mode and continue to run from trampoline and
>   then then start accessing kernel symbols and restore processor context.
>   This enables us to resume even in relocatable kernel context when 
>   kernel might not be loaded at physical addr it has been compiled for.
> 
> o Removed the need for modifying any existing kernel page table.
> 
> o Increased the size of the wakeup routine to 8K. This is required as
>   wake page tables are on trampoline itself and they got to be at 4K
>   boundary, hence one page is not sufficient.
> 
> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>

> +	if ((&wakeup_end - &wakeup_start) > (PAGE_SIZE*2))
>  		printk(KERN_CRIT
> -		       "ACPI: Wakeup code way too big, will crash on attempt to suspend\n");
> +		       "ACPI: Wakeup code way too big, will crash on attempt"
> +		       " to suspend\n");

Hmm, if you split it like
		printk(KERN_CRIT "ACPI: Wakeup code way too big, will crash"
			"on attempt to suspend\n");

...you'll still keep 80-column rule while keeping it readable.

> @@ -159,11 +159,11 @@ wakeup_32:
>  	 */
>  
>  	/* Finally jump in 64bit mode */
> -	ljmp	*(wakeup_long64_vector - __START_KERNEL_map)
> +        ljmp    *(wakeup_long64_vector - wakeup_code)(%esi)

spaces vs. tabs problem.

Otherwise looks good. ACK if it was tested.
									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [Fastboot] [PATCH 12/20] x86_64: 64bit ACPI wakeup trampoline

[Bernhard Walle]

* Pavel Machek <pavel@ucw.cz> [2007-03-07 23:45]:
> 
> > +	if ((&wakeup_end - &wakeup_start) > (PAGE_SIZE*2))
> >  		printk(KERN_CRIT
> > -		       "ACPI: Wakeup code way too big, will crash on attempt to suspend\n");
> > +		       "ACPI: Wakeup code way too big, will crash on attempt"
> > +		       " to suspend\n");
> 
> Hmm, if you split it like
> 		printk(KERN_CRIT "ACPI: Wakeup code way too big, will crash"
> 			"on attempt to suspend\n");
> 
> ...you'll still keep 80-column rule while keeping it readable.

But I guess with a space after "crash" or before "on" :)


Regards,
Bernhard

Re: [PATCH 12/20] x86_64: 64bit ACPI wakeup trampoline

[Vivek Goyal]

On Wed, Mar 07, 2007 at 11:45:08PM +0100, Pavel Machek wrote:
[..]
> 
> > +	if ((&wakeup_end - &wakeup_start) > (PAGE_SIZE*2))
> >  		printk(KERN_CRIT
> > -		       "ACPI: Wakeup code way too big, will crash on attempt to suspend\n");
> > +		       "ACPI: Wakeup code way too big, will crash on attempt"
> > +		       " to suspend\n");
> 
> Hmm, if you split it like
> 		printk(KERN_CRIT "ACPI: Wakeup code way too big, will crash"
> 			"on attempt to suspend\n");
> 
> ...you'll still keep 80-column rule while keeping it readable.
> 

Thanks. Done the changes in attached patch.

> > @@ -159,11 +159,11 @@ wakeup_32:
> >  	 */
> >  
> >  	/* Finally jump in 64bit mode */
> > -	ljmp	*(wakeup_long64_vector - __START_KERNEL_map)
> > +        ljmp    *(wakeup_long64_vector - wakeup_code)(%esi)
> 
> spaces vs. tabs problem.
> 

Thanks. Done the changes in attached patch.

Vivek



o Moved wakeup_level4_pgt into the wakeup routine so we can
  run the kernel above 4G.

o Now we first go to 64bit mode and continue to run from trampoline and
  then then start accessing kernel symbols and restore processor context.
  This enables us to resume even in relocatable kernel context when 
  kernel might not be loaded at physical addr it has been compiled for.

o Removed the need for modifying any existing kernel page table.

o Increased the size of the wakeup routine to 8K. This is required as
  wake page tables are on trampoline itself and they got to be at 4K
  boundary, hence one page is not sufficient.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/acpi/sleep.c  |   23 ++-------------
 arch/x86_64/kernel/acpi/wakeup.S |   59 ++++++++++++++++++++++++---------------
 arch/x86_64/kernel/head.S        |    9 -----
 3 files changed, 41 insertions(+), 50 deletions(-)

diff -puN arch/x86_64/kernel/acpi/sleep.c~x86_64-64bit-ACPI-wakeup-trampoline arch/x86_64/kernel/acpi/sleep.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/acpi/sleep.c~x86_64-64bit-ACPI-wakeup-trampoline	2007-03-07 01:28:11.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/acpi/sleep.c	2007-03-08 18:26:13.000000000 +0530
@@ -60,17 +60,6 @@ extern char wakeup_start, wakeup_end;
 
 extern unsigned long acpi_copy_wakeup_routine(unsigned long);
 
-static pgd_t low_ptr;
-
-static void init_low_mapping(void)
-{
-	pgd_t *slot0 = pgd_offset(current->mm, 0UL);
-	low_ptr = *slot0;
-	set_pgd(slot0, *pgd_offset(current->mm, PAGE_OFFSET));
-	WARN_ON(num_online_cpus() != 1);
-	local_flush_tlb();
-}
-
 /**
  * acpi_save_state_mem - save kernel state
  *
@@ -79,8 +68,6 @@ static void init_low_mapping(void)
  */
 int acpi_save_state_mem(void)
 {
-	init_low_mapping();
-
 	memcpy((void *)acpi_wakeup_address, &wakeup_start,
 	       &wakeup_end - &wakeup_start);
 	acpi_copy_wakeup_routine(acpi_wakeup_address);
@@ -93,8 +80,6 @@ int acpi_save_state_mem(void)
  */
 void acpi_restore_state_mem(void)
 {
-	set_pgd(pgd_offset(current->mm, 0UL), low_ptr);
-	local_flush_tlb();
 }
 
 /**
@@ -107,10 +92,10 @@ void acpi_restore_state_mem(void)
  */
 void __init acpi_reserve_bootmem(void)
 {
-	acpi_wakeup_address = (unsigned long)alloc_bootmem_low(PAGE_SIZE);
-	if ((&wakeup_end - &wakeup_start) > PAGE_SIZE)
-		printk(KERN_CRIT
-		       "ACPI: Wakeup code way too big, will crash on attempt to suspend\n");
+	acpi_wakeup_address = (unsigned long)alloc_bootmem_low(PAGE_SIZE*2);
+	if ((&wakeup_end - &wakeup_start) > (PAGE_SIZE*2))
+		printk(KERN_CRIT "ACPI: Wakeup code way too big, will crash"
+				" on attempt to suspend\n");
 }
 
 static int __init acpi_sleep_setup(char *str)
diff -puN arch/x86_64/kernel/acpi/wakeup.S~x86_64-64bit-ACPI-wakeup-trampoline arch/x86_64/kernel/acpi/wakeup.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/acpi/wakeup.S~x86_64-64bit-ACPI-wakeup-trampoline	2007-03-07 01:28:11.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/acpi/wakeup.S	2007-03-08 18:27:55.000000000 +0530
@@ -1,6 +1,7 @@
 .text
 #include <linux/linkage.h>
 #include <asm/segment.h>
+#include <asm/pgtable.h>
 #include <asm/page.h>
 #include <asm/msr.h>
 
@@ -62,12 +63,15 @@ wakeup_code:
 
 	movb	$0xa2, %al	;  outb %al, $0x80
 	
-	lidt	%ds:idt_48a - wakeup_code
-	xorl	%eax, %eax
-	movw	%ds, %ax			# (Convert %ds:gdt to a linear ptr)
-	shll	$4, %eax
-	addl	$(gdta - wakeup_code), %eax
-	movl	%eax, gdt_48a +2 - wakeup_code
+	mov	%ds, %ax			# Find 32bit wakeup_code addr
+	movzx   %ax, %esi			# (Convert %ds:gdt to a liner ptr)
+	shll    $4, %esi
+						# Fix up the vectors
+	addl    %esi, wakeup_32_vector - wakeup_code
+	addl    %esi, wakeup_long64_vector - wakeup_code
+	addl    %esi, gdt_48a + 2 - wakeup_code # Fixup the gdt pointer
+
+	lidtl	%ds:idt_48a - wakeup_code
 	lgdtl	%ds:gdt_48a - wakeup_code	# load gdt with whatever is
 						# appropriate
 
@@ -80,7 +84,7 @@ wakeup_code:
 
 	.balign 4
 wakeup_32_vector:
-	.long   wakeup_32 - __START_KERNEL_map
+	.long   wakeup_32 - wakeup_code
 	.word   __KERNEL32_CS, 0
 
 	.code32
@@ -103,10 +107,6 @@ wakeup_32:
 	movl	$__KERNEL_DS, %eax
 	movl	%eax, %ds
 
-	movl	saved_magic - __START_KERNEL_map, %eax
-	cmpl	$0x9abcdef0, %eax
-	jne	bogus_32_magic
-
 	movw	$0x0e00 + 'i', %ds:(0xb8012)
 	movb	$0xa8, %al	;  outb %al, $0x80;
 
@@ -120,7 +120,7 @@ wakeup_32:
 	movl	%eax, %cr4
 
 	/* Setup early boot stage 4 level pagetables */
-	movl	$(wakeup_level4_pgt - __START_KERNEL_map), %eax
+	leal    (wakeup_level4_pgt - wakeup_code)(%esi), %eax
 	movl	%eax, %cr3
 
 	/* Enable Long Mode */
@@ -159,11 +159,11 @@ wakeup_32:
 	 */
 
 	/* Finally jump in 64bit mode */
-	ljmp	*(wakeup_long64_vector - __START_KERNEL_map)
+	ljmp    *(wakeup_long64_vector - wakeup_code)(%esi)
 
 	.balign 4
 wakeup_long64_vector:
-	.long   wakeup_long64 - __START_KERNEL_map
+	.long   wakeup_long64 - wakeup_code
 	.word   __KERNEL_CS, 0
 
 .code64
@@ -178,11 +178,16 @@ wakeup_long64:
 	 * addresses where we're currently running on. We have to do that here
 	 * because in 32bit we couldn't load a 64bit linear address.
 	 */
-	lgdt	cpu_gdt_descr - __START_KERNEL_map
+	lgdt	cpu_gdt_descr
 
 	movw	$0x0e00 + 'n', %ds:(0xb8014)
 	movb	$0xa9, %al	;  outb %al, $0x80
 
+	movq    saved_magic, %rax
+	movq    $0x123456789abcdef0, %rdx
+	cmpq    %rdx, %rax
+	jne     bogus_64_magic
+
 	movw	$0x0e00 + 'u', %ds:(0xb8016)
 	
 	nop
@@ -223,20 +228,21 @@ idt_48a:
 gdt_48a:
 	.word	0x800				# gdt limit=2048,
 						#  256 GDT entries
-	.word	0, 0				# gdt base (filled in later)
-	
+	.long   gdta - wakeup_code              # gdt base (relocated in later)
 	
 real_magic:	.quad 0
 video_mode:	.quad 0
 video_flags:	.quad 0
 
+.code16
 bogus_real_magic:
 	movb	$0xba,%al	;  outb %al,$0x80
 	jmp bogus_real_magic
 
-bogus_32_magic:
+.code64
+bogus_64_magic:
 	movb	$0xb3,%al	;  outb %al,$0x80
-	jmp bogus_32_magic
+	jmp bogus_64_magic
 
 bogus_cpu:
 	movb	$0xbc,%al	;  outb %al,$0x80
@@ -263,6 +269,7 @@ bogus_cpu:
 #define VIDEO_FIRST_V7 0x0900
 
 # Setting of user mode (AX=mode ID) => CF=success
+.code16
 mode_seta:
 	movw	%ax, %bx
 #if 0
@@ -313,6 +320,13 @@ wakeup_stack_begin:	# Stack grows down
 .org	0xff0
 wakeup_stack:		# Just below end of page
 
+.org   0x1000
+ENTRY(wakeup_level4_pgt)
+	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.fill   510,8,0
+	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
+	.quad   level3_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
+
 ENTRY(wakeup_end)
 	
 ##
@@ -338,9 +352,10 @@ ENTRY(acpi_copy_wakeup_routine)
 	movq	$0x123456789abcdef0, %rdx
 	movq	%rdx, saved_magic
 
-	movl	saved_magic - __START_KERNEL_map, %eax
-	cmpl	$0x9abcdef0, %eax
-	jne	bogus_32_magic
+	movq    saved_magic, %rax
+	movq    $0x123456789abcdef0, %rdx
+	cmpq    %rdx, %rax
+	jne     bogus_64_magic
 
 	# restore the regs we used
 	popq	%rdx
diff -puN arch/x86_64/kernel/head.S~x86_64-64bit-ACPI-wakeup-trampoline arch/x86_64/kernel/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head.S~x86_64-64bit-ACPI-wakeup-trampoline	2007-03-07 01:28:11.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head.S	2007-03-08 18:17:22.000000000 +0530
@@ -308,15 +308,6 @@ NEXT_PAGE(level2_kernel_pgt)
 
 	.data
 
-#ifdef CONFIG_ACPI_SLEEP
-	.align PAGE_SIZE
-ENTRY(wakeup_level4_pgt)
-	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.fill	510,8,0
-	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
-	.quad	level3_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
-#endif
-
 #ifndef CONFIG_HOTPLUG_CPU
 	__INITDATA
 #endif
_

Re: [PATCH 12/20] x86_64: 64bit ACPI wakeup trampoline

[Pavel Machek]

Hi!

> > ...you'll still keep 80-column rule while keeping it readable.
> > 
> 
> Thanks. Done the changes in attached patch.
> 
> > > @@ -159,11 +159,11 @@ wakeup_32:
> > >  	 */
> > >  
> > >  	/* Finally jump in 64bit mode */
> > > -	ljmp	*(wakeup_long64_vector - __START_KERNEL_map)
> > > +        ljmp    *(wakeup_long64_vector - wakeup_code)(%esi)
> > 
> > spaces vs. tabs problem.
> > 
> 
> Thanks. Done the changes in attached patch.
...
> o Increased the size of the wakeup routine to 8K. This is required as
>   wake page tables are on trampoline itself and they got to be at 4K
>   boundary, hence one page is not sufficient.
> 
> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>

ACK.
								Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[PATCH 13/20] x86_64: Modify discover_ebda to use virtual addresses

[Vivek Goyal]

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/setup.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff -puN arch/x86_64/kernel/setup.c~x86_64-Modify-discover_ebda-to-use-virtual-addresses arch/x86_64/kernel/setup.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/setup.c~x86_64-Modify-discover_ebda-to-use-virtual-addresses	2007-03-07 01:28:51.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/setup.c	2007-03-07 01:28:51.000000000 +0530
@@ -205,10 +205,10 @@ static void discover_ebda(void)
 	 * there is a real-mode segmented pointer pointing to the 
 	 * 4K EBDA area at 0x40E
 	 */
-	ebda_addr = *(unsigned short *)EBDA_ADDR_POINTER;
+	ebda_addr = *(unsigned short *)__va(EBDA_ADDR_POINTER);
 	ebda_addr <<= 4;
 
-	ebda_size = *(unsigned short *)(unsigned long)ebda_addr;
+	ebda_size = *(unsigned short *)__va(ebda_addr);
 
 	/* Round EBDA up to pages */
 	if (ebda_size == 0)
_

[PATCH 14/20] x86_64: Remove the identity mapping as early as possible

[Vivek Goyal]

With the rewrite of the SMP trampoline and the early page
allocator there is nothing that needs identity mapped pages,
once we start executing C code.

So add zap_identity_mappings into head64.c and remove
zap_low_mappings() from much later in the code.  The functions
 are subtly different thus the name change.

This also kills boot_level4_pgt which was from an earlier
attempt to move the identity mappings as early as possible,
and is now no longer needed.  Essentially I have replaced
boot_level4_pgt with trampoline_level4_pgt in trampoline.S

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/kernel/head.S    |   39 ++++++++++++++-------------------------
 arch/x86_64/kernel/head64.c  |   17 +++++++++++------
 arch/x86_64/kernel/setup.c   |    2 --
 arch/x86_64/kernel/setup64.c |    1 -
 arch/x86_64/mm/init.c        |   24 ------------------------
 include/asm-x86_64/pgtable.h |    1 -
 include/asm-x86_64/proto.h   |    2 --
 7 files changed, 25 insertions(+), 61 deletions(-)

diff -puN arch/x86_64/kernel/head64.c~x86_64-Remove-the-identity-mapping-as-early-as-possible arch/x86_64/kernel/head64.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head64.c~x86_64-Remove-the-identity-mapping-as-early-as-possible	2007-03-07 01:29:50.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head64.c	2007-03-07 01:29:50.000000000 +0530
@@ -18,8 +18,16 @@
 #include <asm/setup.h>
 #include <asm/desc.h>
 #include <asm/pgtable.h>
+#include <asm/tlbflush.h>
 #include <asm/sections.h>
 
+static void __init zap_identity_mappings(void)
+{
+	pgd_t *pgd = pgd_offset_k(0UL);
+	pgd_clear(pgd);
+	__flush_tlb();
+}
+
 /* Don't add a printk in there. printk relies on the PDA which is not initialized 
    yet. */
 static void __init clear_bss(void)
@@ -57,18 +65,15 @@ void __init x86_64_start_kernel(char * r
 	/* clear bss before set_intr_gate with early_idt_handler */
 	clear_bss();
 
+	/* Make NULL pointers segfault */
+	zap_identity_mappings();
+
 	for (i = 0; i < IDT_ENTRIES; i++)
 		set_intr_gate(i, early_idt_handler);
 	asm volatile("lidt %0" :: "m" (idt_descr));
 
 	early_printk("Kernel alive\n");
 
-	/*
-	 * switch to init_level4_pgt from boot_level4_pgt
-	 */
-	memcpy(init_level4_pgt, boot_level4_pgt, PTRS_PER_PGD*sizeof(pgd_t));
-	asm volatile("movq %0,%%cr3" :: "r" (__pa_symbol(&init_level4_pgt)));
-
  	for (i = 0; i < NR_CPUS; i++)
  		cpu_pda(i) = &boot_cpu_pda[i];
 
diff -puN arch/x86_64/kernel/head.S~x86_64-Remove-the-identity-mapping-as-early-as-possible arch/x86_64/kernel/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head.S~x86_64-Remove-the-identity-mapping-as-early-as-possible	2007-03-07 01:29:50.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head.S	2007-03-07 01:29:50.000000000 +0530
@@ -71,7 +71,7 @@ startup_32:
 	movl	%eax, %cr4
 
 	/* Setup early boot stage 4 level pagetables */
-	movl	$(boot_level4_pgt - __START_KERNEL_map), %eax
+	movl	$(init_level4_pgt - __START_KERNEL_map), %eax
 	movl	%eax, %cr3
 
 	/* Setup EFER (Extended Feature Enable Register) */
@@ -115,7 +115,7 @@ ENTRY(secondary_startup_64)
 	movq	%rax, %cr4
 
 	/* Setup early boot stage 4 level pagetables. */
-	movq	$(boot_level4_pgt - __START_KERNEL_map), %rax
+	movq	$(init_level4_pgt - __START_KERNEL_map), %rax
 	movq	%rax, %cr3
 
 	/* Check if nx is implemented */
@@ -274,9 +274,19 @@ ENTRY(name)
 	i = i + 1 ;				\
 	.endr
 
+	/*
+	 * This default setting generates an ident mapping at address 0x100000
+	 * and a mapping for the kernel that precisely maps virtual address
+	 * 0xffffffff80000000 to physical address 0x000000. (always using
+	 * 2Mbyte large pages provided by PAE mode)
+	 */
 NEXT_PAGE(init_level4_pgt)
-	/* This gets initialized in x86_64_start_kernel */
-	.fill	512,8,0
+	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.fill	257,8,0
+	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
+	.fill	252,8,0
+	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
+	.quad	level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
 
 NEXT_PAGE(level3_ident_pgt)
 	.quad	level2_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
@@ -307,27 +317,6 @@ NEXT_PAGE(level2_kernel_pgt)
 #undef NEXT_PAGE
 
 	.data
-
-#ifndef CONFIG_HOTPLUG_CPU
-	__INITDATA
-#endif
-	/*
-	 * This default setting generates an ident mapping at address 0x100000
-	 * and a mapping for the kernel that precisely maps virtual address
-	 * 0xffffffff80000000 to physical address 0x000000. (always using
-	 * 2Mbyte large pages provided by PAE mode)
-	 */
-	.align PAGE_SIZE
-ENTRY(boot_level4_pgt)
-	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.fill	257,8,0
-	.quad	level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
-	.fill	252,8,0
-	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
-	.quad	level3_kernel_pgt - __START_KERNEL_map + _PAGE_TABLE
-
-	.data
-
 	.align 16
 	.globl cpu_gdt_descr
 cpu_gdt_descr:
diff -puN arch/x86_64/kernel/setup64.c~x86_64-Remove-the-identity-mapping-as-early-as-possible arch/x86_64/kernel/setup64.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/setup64.c~x86_64-Remove-the-identity-mapping-as-early-as-possible	2007-03-07 01:29:50.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/setup64.c	2007-03-07 01:29:50.000000000 +0530
@@ -201,7 +201,6 @@ void __cpuinit cpu_init (void)
 	/* CPU 0 is initialised in head64.c */
 	if (cpu != 0) {
 		pda_init(cpu);
-		zap_low_mappings(cpu);
 	} else 
 		estacks = boot_exception_stacks; 
 
diff -puN arch/x86_64/kernel/setup.c~x86_64-Remove-the-identity-mapping-as-early-as-possible arch/x86_64/kernel/setup.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/setup.c~x86_64-Remove-the-identity-mapping-as-early-as-possible	2007-03-07 01:29:50.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/setup.c	2007-03-07 01:29:50.000000000 +0530
@@ -274,8 +274,6 @@ void __init setup_arch(char **cmdline_p)
 
 	dmi_scan_machine();
 
-	zap_low_mappings(0);
-
 #ifdef CONFIG_ACPI
 	/*
 	 * Initialize the ACPI boot-time table parser (gets the RSDP and SDT).
diff -puN arch/x86_64/mm/init.c~x86_64-Remove-the-identity-mapping-as-early-as-possible arch/x86_64/mm/init.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/mm/init.c~x86_64-Remove-the-identity-mapping-as-early-as-possible	2007-03-07 01:29:50.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/mm/init.c	2007-03-07 01:29:50.000000000 +0530
@@ -378,21 +378,6 @@ void __meminit init_memory_mapping(unsig
 	__flush_tlb_all();
 }
 
-void __cpuinit zap_low_mappings(int cpu)
-{
-	if (cpu == 0) {
-		pgd_t *pgd = pgd_offset_k(0UL);
-		pgd_clear(pgd);
-	} else {
-		/*
-		 * For AP's, zap the low identity mappings by changing the cr3
-		 * to init_level4_pgt and doing local flush tlb all
-		 */
-		asm volatile("movq %0,%%cr3" :: "r" (__pa_symbol(&init_level4_pgt)));
-	}
-	__flush_tlb_all();
-}
-
 #ifndef CONFIG_NUMA
 void __init paging_init(void)
 {
@@ -569,15 +554,6 @@ void __init mem_init(void)
 		reservedpages << (PAGE_SHIFT-10),
 		datasize >> 10,
 		initsize >> 10);
-
-#ifdef CONFIG_SMP
-	/*
-	 * Sync boot_level4_pgt mappings with the init_level4_pgt
-	 * except for the low identity mappings which are already zapped
-	 * in init_level4_pgt. This sync-up is essential for AP's bringup
-	 */
-	memcpy(boot_level4_pgt+1, init_level4_pgt+1, (PTRS_PER_PGD-1)*sizeof(pgd_t));
-#endif
 }
 
 void free_init_pages(char *what, unsigned long begin, unsigned long end)
diff -puN include/asm-x86_64/pgtable.h~x86_64-Remove-the-identity-mapping-as-early-as-possible include/asm-x86_64/pgtable.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/pgtable.h~x86_64-Remove-the-identity-mapping-as-early-as-possible	2007-03-07 01:29:50.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/pgtable.h	2007-03-07 01:29:50.000000000 +0530
@@ -18,7 +18,6 @@ extern pud_t level3_kernel_pgt[512];
 extern pud_t level3_ident_pgt[512];
 extern pmd_t level2_kernel_pgt[512];
 extern pgd_t init_level4_pgt[];
-extern pgd_t boot_level4_pgt[];
 extern unsigned long __supported_pte_mask;
 
 #define swapper_pg_dir init_level4_pgt
diff -puN include/asm-x86_64/proto.h~x86_64-Remove-the-identity-mapping-as-early-as-possible include/asm-x86_64/proto.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/proto.h~x86_64-Remove-the-identity-mapping-as-early-as-possible	2007-03-07 01:29:50.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/proto.h	2007-03-07 01:29:50.000000000 +0530
@@ -11,8 +11,6 @@ struct pt_regs;
 extern void start_kernel(void);
 extern void pda_init(int); 
 
-extern void zap_low_mappings(int cpu);
-
 extern void early_idt_handler(void);
 
 extern void mcheck_init(struct cpuinfo_x86 *c);
_

[PATCH 15/20] Move swsusp __pa() dependent code to arch portion

[Vivek Goyal]

o __pa() should be used only on kernel linearly mapped virtual addresses
  and not on kernel text and data addresses.

o Hibernation code needs to determine the physical address associated
  with kernel symbol to mark a section boundary which contains pages which
  don't have to be saved and restored during hibernate/resume operation.

o Move this piece of code in arch dependent section. So that architectures
  which don't have kernel text/data mapped into kernel linearly mapped
  region can come up with their own ways of determining physical addresses
  associated with a kernel text.

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/i386/power/suspend.c     |   14 ++++++++++++++
 arch/powerpc/kernel/Makefile  |    1 +
 arch/powerpc/kernel/suspend.c |   24 ++++++++++++++++++++++++
 arch/x86_64/kernel/suspend.c  |   14 ++++++++++++++
 kernel/power/power.h          |    5 ++---
 kernel/power/snapshot.c       |   11 -----------
 6 files changed, 55 insertions(+), 14 deletions(-)

diff -puN arch/i386/power/suspend.c~move-swsusp-__pa-dependent-code-to-arch-portion arch/i386/power/suspend.c
--- linux-2.6.21-rc2-reloc/arch/i386/power/suspend.c~move-swsusp-__pa-dependent-code-to-arch-portion	2007-03-07 01:30:18.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/i386/power/suspend.c	2007-03-07 01:30:18.000000000 +0530
@@ -16,6 +16,9 @@
 /* Defined in arch/i386/power/swsusp.S */
 extern int restore_image(void);
 
+/* References to section boundaries */
+extern const void __nosave_begin, __nosave_end;
+
 /* Pointer to the temporary resume page tables */
 pgd_t *resume_pg_dir;
 
@@ -156,3 +159,14 @@ int swsusp_arch_resume(void)
 	restore_image();
 	return 0;
 }
+
+/*
+ *	pfn_is_nosave - check if given pfn is in the 'nosave' section
+ */
+
+int pfn_is_nosave(unsigned long pfn)
+{
+	unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
+	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
+	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
+}
diff -puN arch/powerpc/kernel/Makefile~move-swsusp-__pa-dependent-code-to-arch-portion arch/powerpc/kernel/Makefile
--- linux-2.6.21-rc2-reloc/arch/powerpc/kernel/Makefile~move-swsusp-__pa-dependent-code-to-arch-portion	2007-03-07 01:30:18.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/powerpc/kernel/Makefile	2007-03-07 01:30:18.000000000 +0530
@@ -37,6 +37,7 @@ obj-$(CONFIG_CRASH_DUMP)	+= crash_dump.o
 obj-$(CONFIG_6xx)		+= idle_6xx.o l2cr_6xx.o cpu_setup_6xx.o
 obj-$(CONFIG_TAU)		+= tau_6xx.o
 obj32-$(CONFIG_SOFTWARE_SUSPEND) += swsusp_32.o
+obj-$(CONFIG_SOFTWARE_SUSPEND) += suspend.o
 obj32-$(CONFIG_MODULES)		+= module_32.o
 
 ifeq ($(CONFIG_PPC_MERGE),y)
diff -puN /dev/null arch/powerpc/kernel/suspend.c
--- /dev/null	2007-03-07 00:46:17.354096448 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/powerpc/kernel/suspend.c	2007-03-07 01:30:18.000000000 +0530
@@ -0,0 +1,24 @@
+/*
+ * Suspend support specific for power.
+ *
+ * Distribute under GPLv2
+ *
+ * Copyright (c) 2002 Pavel Machek <pavel@suse.cz>
+ * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
+ */
+
+#include <asm/page.h>
+
+/* References to section boundaries */
+extern const void __nosave_begin, __nosave_end;
+
+/*
+ *	pfn_is_nosave - check if given pfn is in the 'nosave' section
+ */
+
+int pfn_is_nosave(unsigned long pfn)
+{
+	unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
+	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT;
+	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
+}
diff -puN arch/x86_64/kernel/suspend.c~move-swsusp-__pa-dependent-code-to-arch-portion arch/x86_64/kernel/suspend.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/suspend.c~move-swsusp-__pa-dependent-code-to-arch-portion	2007-03-07 01:30:18.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/suspend.c	2007-03-07 01:30:18.000000000 +0530
@@ -13,6 +13,9 @@
 #include <asm/page.h>
 #include <asm/pgtable.h>
 
+/* References to section boundaries */
+extern const void __nosave_begin, __nosave_end;
+
 struct saved_context saved_context;
 
 unsigned long saved_context_eax, saved_context_ebx, saved_context_ecx, saved_context_edx;
@@ -220,4 +223,15 @@ int swsusp_arch_resume(void)
 	restore_image();
 	return 0;
 }
+
+/*
+ *	pfn_is_nosave - check if given pfn is in the 'nosave' section
+ */
+
+int pfn_is_nosave(unsigned long pfn)
+{
+	unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
+	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
+	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
+}
 #endif /* CONFIG_SOFTWARE_SUSPEND */
diff -puN kernel/power/power.h~move-swsusp-__pa-dependent-code-to-arch-portion kernel/power/power.h
--- linux-2.6.21-rc2-reloc/kernel/power/power.h~move-swsusp-__pa-dependent-code-to-arch-portion	2007-03-07 01:30:18.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/kernel/power/power.h	2007-03-07 01:30:18.000000000 +0530
@@ -23,6 +23,8 @@ static inline int pm_suspend_disk(void)
 }
 #endif
 
+extern int pfn_is_nosave(unsigned long);
+
 extern struct mutex pm_mutex;
 
 #define power_attr(_name) \
@@ -37,9 +39,6 @@ static struct subsys_attribute _name##_a
 
 extern struct subsystem power_subsys;
 
-/* References to section boundaries */
-extern const void __nosave_begin, __nosave_end;
-
 /* Preferred image size in bytes (default 500 MB) */
 extern unsigned long image_size;
 extern int in_suspend;
diff -puN kernel/power/snapshot.c~move-swsusp-__pa-dependent-code-to-arch-portion kernel/power/snapshot.c
--- linux-2.6.21-rc2-reloc/kernel/power/snapshot.c~move-swsusp-__pa-dependent-code-to-arch-portion	2007-03-07 01:30:18.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/kernel/power/snapshot.c	2007-03-07 01:30:18.000000000 +0530
@@ -651,17 +651,6 @@ static inline unsigned int count_highmem
 #endif /* CONFIG_HIGHMEM */
 
 /**
- *	pfn_is_nosave - check if given pfn is in the 'nosave' section
- */
-
-static inline int pfn_is_nosave(unsigned long pfn)
-{
-	unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
-	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT;
-	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
-}
-
-/**
  *	saveable - Determine whether a non-highmem page should be included in
  *	the suspend image.
  *
_

Re: [PATCH 15/20] Move swsusp __pa() dependent code to arch portion

[Pavel Machek]

Hi!

> o __pa() should be used only on kernel linearly mapped virtual addresses
>   and not on kernel text and data addresses.
> 
> o Hibernation code needs to determine the physical address associated
>   with kernel symbol to mark a section boundary which contains pages which
>   don't have to be saved and restored during hibernate/resume operation.
> 
> o Move this piece of code in arch dependent section. So that architectures
>   which don't have kernel text/data mapped into kernel linearly mapped
>   region can come up with their own ways of determining physical addresses
>   associated with a kernel text.
> 
> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>

...hmm, but that means 3 copies of same code. Can we put the

> +/*
> + *	pfn_is_nosave - check if given pfn is in the 'nosave' section
> + */
> +
> +int pfn_is_nosave(unsigned long pfn)
> +{
> +	unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
> +	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
> +	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
> +}

...in asm-generic/suspend.h (or something) and then just include it?
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH 15/20] Move swsusp __pa() dependent code to arch portion

[Vivek Goyal]

On Wed, Mar 07, 2007 at 11:47:40PM +0100, Pavel Machek wrote:
> Hi!
> 
> > o __pa() should be used only on kernel linearly mapped virtual addresses
> >   and not on kernel text and data addresses.
> > 
> > o Hibernation code needs to determine the physical address associated
> >   with kernel symbol to mark a section boundary which contains pages which
> >   don't have to be saved and restored during hibernate/resume operation.
> > 
> > o Move this piece of code in arch dependent section. So that architectures
> >   which don't have kernel text/data mapped into kernel linearly mapped
> >   region can come up with their own ways of determining physical addresses
> >   associated with a kernel text.
> > 
> > Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
> 
> ...hmm, but that means 3 copies of same code. Can we put the
> 

Actually it is not exactly same code. i386 and x86_64 use __pa_symbol()
and powerpc uses __pa() for determining physical address associated with
a kernel text symbol. That's the precise intent here. Leave it to arch
code to decide how to calculate physical address associated with a kernel
symbol.

> > +/*
> > + *	pfn_is_nosave - check if given pfn is in the 'nosave' section
> > + */
> > +
> > +int pfn_is_nosave(unsigned long pfn)
> > +{
> > +	unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
> > +	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
> > +	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
> > +}
> 
> ...in asm-generic/suspend.h (or something) and then just include it?
> 									Pavel

As code is not exactly same, we can't put it in asm-generic/suspend.h.

Thanks
Vivek

Re: [PATCH 15/20] Move swsusp __pa() dependent code to arch portion

[Pavel Machek]

Hi!

> > > +int pfn_is_nosave(unsigned long pfn)
> > > +{
> > > +	unsigned long nosave_begin_pfn = __pa_symbol(&__nosave_begin) >> PAGE_SHIFT;
> > > +	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa_symbol(&__nosave_end)) >> PAGE_SHIFT;
> > > +	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
> > > +}
> > 
> > ...in asm-generic/suspend.h (or something) and then just include it?
> > 									Pavel
> 
> As code is not exactly same, we can't put it in asm-generic/suspend.h.

Ok... ACK on the original patch, then.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[PATCH 16/20] swsusp: do not use virt_to_page on kernel data address

[Vivek Goyal]

o virt_to_page() call should be used on kernel linear addresses and not
  on kernel text and data addresses. Swsusp code uses it on kernel data
  (statically allocated swsusp_header).

o Allocate swsusp_header dynamically so that virt_to_page() can be used
  safely.

o I am changing this because in next few patches, __pa() on x86_64 will
  no longer support kernel text and data addresses and hibernation breaks. 

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 kernel/power/swap.c |   42 +++++++++++++++++++++++++++---------------
 1 file changed, 27 insertions(+), 15 deletions(-)

diff -puN kernel/power/swap.c~swsusp-do-not-use-virt_to_page-on-kernel-data-addr kernel/power/swap.c
--- linux-2.6.21-rc2-reloc/kernel/power/swap.c~swsusp-do-not-use-virt_to_page-on-kernel-data-addr	2007-03-07 01:30:43.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/kernel/power/swap.c	2007-03-07 01:30:43.000000000 +0530
@@ -33,12 +33,14 @@ extern char resume_file[];
 
 #define SWSUSP_SIG	"S1SUSPEND"
 
-static struct swsusp_header {
+struct swsusp_header {
 	char reserved[PAGE_SIZE - 20 - sizeof(sector_t)];
 	sector_t image;
 	char	orig_sig[10];
 	char	sig[10];
-} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header;
+} __attribute__((packed));
+
+static struct swsusp_header *swsusp_header;
 
 /*
  * General things
@@ -141,14 +143,14 @@ static int mark_swapfiles(sector_t start
 {
 	int error;
 
-	bio_read_page(swsusp_resume_block, &swsusp_header, NULL);
-	if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) ||
-	    !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) {
-		memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10);
-		memcpy(swsusp_header.sig,SWSUSP_SIG, 10);
-		swsusp_header.image = start;
+	bio_read_page(swsusp_resume_block, swsusp_header, NULL);
+	if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
+	    !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
+		memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
+		memcpy(swsusp_header->sig,SWSUSP_SIG, 10);
+		swsusp_header->image = start;
 		error = bio_write_page(swsusp_resume_block,
-					&swsusp_header, NULL);
+					swsusp_header, NULL);
 	} else {
 		printk(KERN_ERR "swsusp: Swap header not found!\n");
 		error = -ENODEV;
@@ -564,7 +566,7 @@ int swsusp_read(void)
 	if (error < PAGE_SIZE)
 		return error < 0 ? error : -EFAULT;
 	header = (struct swsusp_info *)data_of(snapshot);
-	error = get_swap_reader(&handle, swsusp_header.image);
+	error = get_swap_reader(&handle, swsusp_header->image);
 	if (!error)
 		error = swap_read_page(&handle, header, NULL);
 	if (!error)
@@ -591,17 +593,17 @@ int swsusp_check(void)
 	resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
 	if (!IS_ERR(resume_bdev)) {
 		set_blocksize(resume_bdev, PAGE_SIZE);
-		memset(&swsusp_header, 0, sizeof(swsusp_header));
+		memset(swsusp_header, 0, sizeof(PAGE_SIZE));
 		error = bio_read_page(swsusp_resume_block,
-					&swsusp_header, NULL);
+					swsusp_header, NULL);
 		if (error)
 			return error;
 
-		if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) {
-			memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10);
+		if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) {
+			memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
 			/* Reset swap signature now */
 			error = bio_write_page(swsusp_resume_block,
-						&swsusp_header, NULL);
+						swsusp_header, NULL);
 		} else {
 			return -EINVAL;
 		}
@@ -632,3 +634,13 @@ void swsusp_close(void)
 
 	blkdev_put(resume_bdev);
 }
+
+static int swsusp_header_init(void)
+{
+	swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
+	if (!swsusp_header)
+		panic("Could not allocate memory for swsusp_header\n");
+	return 0;
+}
+
+core_initcall(swsusp_header_init);
_

Re: [PATCH 16/20] swsusp: do not use virt_to_page on kernel data address

[Pavel Machek]

Hi!

> o virt_to_page() call should be used on kernel linear addresses and not
>   on kernel text and data addresses. Swsusp code uses it on kernel data
>   (statically allocated swsusp_header).
> 
> o Allocate swsusp_header dynamically so that virt_to_page() can be used
>   safely.
> 
> o I am changing this because in next few patches, __pa() on x86_64 will
>   no longer support kernel text and data addresses and hibernation breaks. 
> 
> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>

> +static int swsusp_header_init(void)
> +{
> +	swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
> +	if (!swsusp_header)
> +		panic("Could not allocate memory for swsusp_header\n");
> +	return 0;
> +}
> +
> +core_initcall(swsusp_header_init);

I do not like the panic, but I guess it is okay as we are running
during boot? (Could you add a comment?) Otherwise ok.

								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH 16/20] swsusp: do not use virt_to_page on kernel data address

[Vivek Goyal]

On Wed, Mar 07, 2007 at 11:49:15PM +0100, Pavel Machek wrote:
> Hi!
> 
> > o virt_to_page() call should be used on kernel linear addresses and not
> >   on kernel text and data addresses. Swsusp code uses it on kernel data
> >   (statically allocated swsusp_header).
> > 
> > o Allocate swsusp_header dynamically so that virt_to_page() can be used
> >   safely.
> > 
> > o I am changing this because in next few patches, __pa() on x86_64 will
> >   no longer support kernel text and data addresses and hibernation breaks. 
> > 
> > Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
> 
> > +static int swsusp_header_init(void)
> > +{
> > +	swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
> > +	if (!swsusp_header)
> > +		panic("Could not allocate memory for swsusp_header\n");
> > +	return 0;
> > +}
> > +
> > +core_initcall(swsusp_header_init);
> 
> I do not like the panic, but I guess it is okay as we are running
> during boot? (Could you add a comment?) Otherwise ok.
> 

Hi Pavel,

Yes, it is an initcall and this memory page will be allocated during
boot time. Not very sure what comment to put there. To me it seems
pretty obivious with "core_initcall".

Thanks
Vivek

Re: [PATCH 16/20] swsusp: do not use virt_to_page on kernel data address

[Pavel Machek]

Hi!

> > > Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
> > 
> > > +static int swsusp_header_init(void)
> > > +{
> > > +	swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
> > > +	if (!swsusp_header)
> > > +		panic("Could not allocate memory for swsusp_header\n");
> > > +	return 0;
> > > +}
> > > +
> > > +core_initcall(swsusp_header_init);
> > 
> > I do not like the panic, but I guess it is okay as we are running
> > during boot? (Could you add a comment?) Otherwise ok.
> > 
> 
> Hi Pavel,
> 
> Yes, it is an initcall and this memory page will be allocated during
> boot time. Not very sure what comment to put there. To me it seems
> pretty obivious with "core_initcall".

I'd put "/* running at boot time, so allocation can't fail */" there
(and maybe just replace panic with BUG_ON), but I guess that's not
important.

ACK.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH 16/20] swsusp: do not use virt_to_page on kernel data address

[Pavel Machek]

Hi!

> o virt_to_page() call should be used on kernel linear addresses and not
>   on kernel text and data addresses. Swsusp code uses it on kernel data
>   (statically allocated swsusp_header).
> 
> o Allocate swsusp_header dynamically so that virt_to_page() can be used
>   safely.
> 
> o I am changing this because in next few patches, __pa() on x86_64 will
>   no longer support kernel text and data addresses and hibernation breaks. 
> 
> Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>

(I assume this was tested, too?)
									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH 16/20] swsusp: do not use virt_to_page on kernel data address

[Nigel Cunningham]

Hi.

On Wed, 2007-03-07 at 23:50 +0100, Pavel Machek wrote:
> Hi!
> 
> > o virt_to_page() call should be used on kernel linear addresses and not
> >   on kernel text and data addresses. Swsusp code uses it on kernel data
> >   (statically allocated swsusp_header).
> > 
> > o Allocate swsusp_header dynamically so that virt_to_page() can be used
> >   safely.
> > 
> > o I am changing this because in next few patches, __pa() on x86_64 will
> >   no longer support kernel text and data addresses and hibernation breaks. 
> > 
> > Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
> 
> (I assume this was tested, too?)

Absolutely.

Nigel

Re: [PATCH 16/20] swsusp: do not use virt_to_page on kernel data address

[Vivek Goyal]

On Wed, Mar 07, 2007 at 11:50:06PM +0100, Pavel Machek wrote:
> Hi!
> 
> > o virt_to_page() call should be used on kernel linear addresses and not
> >   on kernel text and data addresses. Swsusp code uses it on kernel data
> >   (statically allocated swsusp_header).
> > 
> > o Allocate swsusp_header dynamically so that virt_to_page() can be used
> >   safely.
> > 
> > o I am changing this because in next few patches, __pa() on x86_64 will
> >   no longer support kernel text and data addresses and hibernation breaks. 
> > 
> > Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
> 
> (I assume this was tested, too?)
> 									Pavel

Yes. I have tested this and it works fine.

Thanks
Vivek

Re: [PATCH 16/20] swsusp: do not use virt_to_page on kernel data address

[Pavel Machek]

Hi!

> > > o virt_to_page() call should be used on kernel linear addresses and not
> > >   on kernel text and data addresses. Swsusp code uses it on kernel data
> > >   (statically allocated swsusp_header).
> > > 
> > > o Allocate swsusp_header dynamically so that virt_to_page() can be used
> > >   safely.
> > > 
> > > o I am changing this because in next few patches, __pa() on x86_64 will
> > >   no longer support kernel text and data addresses and hibernation breaks. 
> > > 
> > > Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
> > 
> > (I assume this was tested, too?)
> 
> Yes. I have tested this and it works fine.

ACK from me, then.
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[PATCH 17/20] x86_64: __pa and __pa_symbol address space separation

[Vivek Goyal]

Currently __pa_symbol is for use with symbols in the kernel address
map and __pa is for use with pointers into the physical memory map.
But the code is implemented so you can usually interchange the two.

__pa which is much more common can be implemented much more cheaply
if it is it doesn't have to worry about any other kernel address
spaces.  This is especially true with a relocatable kernel as
__pa_symbol needs to peform an extra variable read to resolve
the address.

There is a third macro that is added for the vsyscall data
__pa_vsymbol for finding the physical addesses of vsyscall pages.

Most of this patch is simply sorting through the references to
__pa or __pa_symbol and using the proper one.  A little of
it is continuing to use a physical address when we have it
instead of recalculating it several times.

swapper_pgd is now NULL.  leave_mm now uses init_mm.pgd
and init_mm.pgd is initialized at boot (instead of compile time)
to the physmem virtual mapping of init_level4_pgd.  The
physical address changed.

Except for the for EMPTY_ZERO page all of the remaining references
to __pa_symbol appear to be during kernel initialization.  So this
should reduce the cost of __pa in the common case, even on a relocated
kernel.

As this is technically a semantic change we need to be on the lookout
for anything I missed.  But it works for me (tm).

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/i386/kernel/alternative.c     |    8 ++++----
 arch/i386/mm/init.c                |   15 ++++++++-------
 arch/x86_64/kernel/machine_kexec.c |   14 +++++++-------
 arch/x86_64/kernel/setup.c         |    9 +++++----
 arch/x86_64/kernel/smp.c           |    2 +-
 arch/x86_64/kernel/vsyscall.c      |    9 +++++++--
 arch/x86_64/mm/init.c              |   21 +++++++++++----------
 arch/x86_64/mm/pageattr.c          |   16 ++++++++--------
 include/asm-x86_64/page.h          |    6 ++----
 include/asm-x86_64/pgtable.h       |    4 ++--
 10 files changed, 55 insertions(+), 49 deletions(-)

diff -puN arch/i386/kernel/alternative.c~x86_64-__pa-and-__pa_symbol-address-space-separation arch/i386/kernel/alternative.c
--- linux-2.6.21-rc2-reloc/arch/i386/kernel/alternative.c~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/i386/kernel/alternative.c	2007-03-07 01:31:03.000000000 +0530
@@ -389,8 +389,8 @@ void __init alternative_instructions(voi
 	if (no_replacement) {
 		printk(KERN_INFO "(SMP-)alternatives turned off\n");
 		free_init_pages("SMP alternatives",
-				(unsigned long)__smp_alt_begin,
-				(unsigned long)__smp_alt_end);
+				__pa_symbol(&__smp_alt_begin),
+				__pa_symbol(&__smp_alt_end));
 		return;
 	}
 
@@ -419,8 +419,8 @@ void __init alternative_instructions(voi
 						_text, _etext);
 		}
 		free_init_pages("SMP alternatives",
-				(unsigned long)__smp_alt_begin,
-				(unsigned long)__smp_alt_end);
+				__pa_symbol(&__smp_alt_begin),
+				__pa_symbol(&__smp_alt_end));
 	} else {
 		alternatives_smp_save(__smp_alt_instructions,
 				      __smp_alt_instructions_end);
diff -puN arch/i386/mm/init.c~x86_64-__pa-and-__pa_symbol-address-space-separation arch/i386/mm/init.c
--- linux-2.6.21-rc2-reloc/arch/i386/mm/init.c~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/i386/mm/init.c	2007-03-07 01:31:03.000000000 +0530
@@ -774,10 +774,11 @@ void free_init_pages(char *what, unsigne
 	unsigned long addr;
 
 	for (addr = begin; addr < end; addr += PAGE_SIZE) {
-		ClearPageReserved(virt_to_page(addr));
-		init_page_count(virt_to_page(addr));
-		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
-		free_page(addr);
+		struct page *page = pfn_to_page(addr >> PAGE_SHIFT);
+		ClearPageReserved(page);
+		init_page_count(page);
+		memset(page_address(page), POISON_FREE_INITMEM, PAGE_SIZE);
+		__free_page(page);
 		totalram_pages++;
 	}
 	printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
@@ -786,14 +787,14 @@ void free_init_pages(char *what, unsigne
 void free_initmem(void)
 {
 	free_init_pages("unused kernel memory",
-			(unsigned long)(&__init_begin),
-			(unsigned long)(&__init_end));
+			__pa_symbol(&__init_begin),
+			__pa_symbol(&__init_end));
 }
 
 #ifdef CONFIG_BLK_DEV_INITRD
 void free_initrd_mem(unsigned long start, unsigned long end)
 {
-	free_init_pages("initrd memory", start, end);
+	free_init_pages("initrd memory", __pa(start), __pa(end));
 }
 #endif
 
diff -puN arch/x86_64/kernel/machine_kexec.c~x86_64-__pa-and-__pa_symbol-address-space-separation arch/x86_64/kernel/machine_kexec.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/machine_kexec.c~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/machine_kexec.c	2007-03-07 01:31:03.000000000 +0530
@@ -191,19 +191,19 @@ NORET_TYPE void machine_kexec(struct kim
 
 	page_list[PA_CONTROL_PAGE] = __pa(control_page);
 	page_list[VA_CONTROL_PAGE] = (unsigned long)relocate_kernel;
-	page_list[PA_PGD] = __pa(kexec_pgd);
+	page_list[PA_PGD] = __pa_symbol(&kexec_pgd);
 	page_list[VA_PGD] = (unsigned long)kexec_pgd;
-	page_list[PA_PUD_0] = __pa(kexec_pud0);
+	page_list[PA_PUD_0] = __pa_symbol(&kexec_pud0);
 	page_list[VA_PUD_0] = (unsigned long)kexec_pud0;
-	page_list[PA_PMD_0] = __pa(kexec_pmd0);
+	page_list[PA_PMD_0] = __pa_symbol(&kexec_pmd0);
 	page_list[VA_PMD_0] = (unsigned long)kexec_pmd0;
-	page_list[PA_PTE_0] = __pa(kexec_pte0);
+	page_list[PA_PTE_0] = __pa_symbol(&kexec_pte0);
 	page_list[VA_PTE_0] = (unsigned long)kexec_pte0;
-	page_list[PA_PUD_1] = __pa(kexec_pud1);
+	page_list[PA_PUD_1] = __pa_symbol(&kexec_pud1);
 	page_list[VA_PUD_1] = (unsigned long)kexec_pud1;
-	page_list[PA_PMD_1] = __pa(kexec_pmd1);
+	page_list[PA_PMD_1] = __pa_symbol(&kexec_pmd1);
 	page_list[VA_PMD_1] = (unsigned long)kexec_pmd1;
-	page_list[PA_PTE_1] = __pa(kexec_pte1);
+	page_list[PA_PTE_1] = __pa_symbol(&kexec_pte1);
 	page_list[VA_PTE_1] = (unsigned long)kexec_pte1;
 
 	page_list[PA_TABLE_PAGE] =
diff -puN arch/x86_64/kernel/setup.c~x86_64-__pa-and-__pa_symbol-address-space-separation arch/x86_64/kernel/setup.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/setup.c~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/setup.c	2007-03-07 01:31:03.000000000 +0530
@@ -243,11 +243,12 @@ void __init setup_arch(char **cmdline_p)
 	init_mm.end_code = (unsigned long) &_etext;
 	init_mm.end_data = (unsigned long) &_edata;
 	init_mm.brk = (unsigned long) &_end;
+	init_mm.pgd = __va(__pa_symbol(&init_level4_pgt));
 
-	code_resource.start = virt_to_phys(&_text);
-	code_resource.end = virt_to_phys(&_etext)-1;
-	data_resource.start = virt_to_phys(&_etext);
-	data_resource.end = virt_to_phys(&_edata)-1;
+	code_resource.start = __pa_symbol(&_text);
+	code_resource.end = __pa_symbol(&_etext)-1;
+	data_resource.start = __pa_symbol(&_etext);
+	data_resource.end = __pa_symbol(&_edata)-1;
 
 	early_identify_cpu(&boot_cpu_data);
 
diff -puN arch/x86_64/kernel/smp.c~x86_64-__pa-and-__pa_symbol-address-space-separation arch/x86_64/kernel/smp.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/smp.c~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/smp.c	2007-03-07 01:31:03.000000000 +0530
@@ -76,7 +76,7 @@ static inline void leave_mm(int cpu)
 	if (read_pda(mmu_state) == TLBSTATE_OK)
 		BUG();
 	cpu_clear(cpu, read_pda(active_mm)->cpu_vm_mask);
-	load_cr3(swapper_pg_dir);
+	load_cr3(init_mm.pgd);
 }
 
 /*
diff -puN arch/x86_64/kernel/vsyscall.c~x86_64-__pa-and-__pa_symbol-address-space-separation arch/x86_64/kernel/vsyscall.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/vsyscall.c~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/vsyscall.c	2007-03-07 01:31:03.000000000 +0530
@@ -45,6 +45,11 @@
 
 #define __vsyscall(nr) __attribute__ ((unused,__section__(".vsyscall_" #nr)))
 #define __syscall_clobber "r11","rcx","memory"
+#define __pa_vsymbol(x)			\
+	({unsigned long v;  		\
+	extern char __vsyscall_0; 	\
+	  asm("" : "=r" (v) : "0" (x)); \
+	  ((v - VSYSCALL_FIRST_PAGE) + __pa_symbol(&__vsyscall_0)); })
 
 struct vsyscall_gtod_data_t {
 	seqlock_t lock;
@@ -224,10 +229,10 @@ static int vsyscall_sysctl_change(ctl_ta
 		return ret;
 	/* gcc has some trouble with __va(__pa()), so just do it this
 	   way. */
-	map1 = ioremap(__pa_symbol(&vsysc1), 2);
+	map1 = ioremap(__pa_vsymbol(&vsysc1), 2);
 	if (!map1)
 		return -ENOMEM;
-	map2 = ioremap(__pa_symbol(&vsysc2), 2);
+	map2 = ioremap(__pa_vsymbol(&vsysc2), 2);
 	if (!map2) {
 		ret = -ENOMEM;
 		goto out;
diff -puN arch/x86_64/mm/init.c~x86_64-__pa-and-__pa_symbol-address-space-separation arch/x86_64/mm/init.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/mm/init.c~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/mm/init.c	2007-03-07 01:31:03.000000000 +0530
@@ -565,11 +565,11 @@ void free_init_pages(char *what, unsigne
 
 	printk(KERN_INFO "Freeing %s: %ldk freed\n", what, (end - begin) >> 10);
 	for (addr = begin; addr < end; addr += PAGE_SIZE) {
-		ClearPageReserved(virt_to_page(addr));
-		init_page_count(virt_to_page(addr));
-		memset((void *)(addr & ~(PAGE_SIZE-1)),
-			POISON_FREE_INITMEM, PAGE_SIZE);
-		free_page(addr);
+		struct page *page = pfn_to_page(addr >> PAGE_SHIFT);
+		ClearPageReserved(page);
+		init_page_count(page);
+		memset(page_address(page), POISON_FREE_INITMEM, PAGE_SIZE);
+		__free_page(page);
 		totalram_pages++;
 	}
 }
@@ -579,17 +579,18 @@ void free_initmem(void)
 	memset(__initdata_begin, POISON_FREE_INITDATA,
 		__initdata_end - __initdata_begin);
 	free_init_pages("unused kernel memory",
-			(unsigned long)(&__init_begin),
-			(unsigned long)(&__init_end));
+			__pa_symbol(&__init_begin),
+			__pa_symbol(&__init_end));
 }
 
 #ifdef CONFIG_DEBUG_RODATA
 
 void mark_rodata_ro(void)
 {
-	unsigned long addr = (unsigned long)__start_rodata;
+	unsigned long addr = (unsigned long)__va(__pa_symbol(&__start_rodata));
+	unsigned long end  = (unsigned long)__va(__pa_symbol(&__end_rodata));
 
-	for (; addr < (unsigned long)__end_rodata; addr += PAGE_SIZE)
+	for (; addr < end; addr += PAGE_SIZE)
 		change_page_attr_addr(addr, 1, PAGE_KERNEL_RO);
 
 	printk ("Write protecting the kernel read-only data: %luk\n",
@@ -608,7 +609,7 @@ void mark_rodata_ro(void)
 #ifdef CONFIG_BLK_DEV_INITRD
 void free_initrd_mem(unsigned long start, unsigned long end)
 {
-	free_init_pages("initrd memory", start, end);
+	free_init_pages("initrd memory", __pa(start), __pa(end));
 }
 #endif
 
diff -puN arch/x86_64/mm/pageattr.c~x86_64-__pa-and-__pa_symbol-address-space-separation arch/x86_64/mm/pageattr.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/mm/pageattr.c~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/mm/pageattr.c	2007-03-07 01:31:03.000000000 +0530
@@ -51,7 +51,6 @@ static struct page *split_large_page(uns
 	SetPagePrivate(base);
 	page_private(base) = 0;
 
-	address = __pa(address);
 	addr = address & LARGE_PAGE_MASK; 
 	pbase = (pte_t *)page_address(base);
 	for (i = 0; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE) {
@@ -101,13 +100,12 @@ static inline void save_page(struct page
  * No more special protections in this 2/4MB area - revert to a
  * large page again. 
  */
-static void revert_page(unsigned long address, pgprot_t ref_prot)
+static void revert_page(unsigned long address, unsigned long pfn, pgprot_t ref_prot)
 {
 	pgd_t *pgd;
 	pud_t *pud;
 	pmd_t *pmd;
 	pte_t large_pte;
-	unsigned long pfn;
 
 	pgd = pgd_offset_k(address);
 	BUG_ON(pgd_none(*pgd));
@@ -115,7 +113,6 @@ static void revert_page(unsigned long ad
 	BUG_ON(pud_none(*pud));
 	pmd = pmd_offset(pud, address);
 	BUG_ON(pmd_val(*pmd) & _PAGE_PSE);
-	pfn = (__pa(address) & LARGE_PAGE_MASK) >> PAGE_SHIFT;
 	large_pte = pfn_pte(pfn, ref_prot);
 	large_pte = pte_mkhuge(large_pte);
 	set_pte((pte_t *)pmd, large_pte);
@@ -141,7 +138,8 @@ __change_page_attr(unsigned long address
  			 */
 			struct page *split;
 			ref_prot2 = pte_pgprot(pte_clrhuge(*kpte));
-			split = split_large_page(address, prot, ref_prot2);
+			split = split_large_page(pfn << PAGE_SHIFT, prot,
+							ref_prot2);
 			if (!split)
 				return -ENOMEM;
 			set_pte(kpte, mk_pte(split, ref_prot2));
@@ -160,7 +158,7 @@ __change_page_attr(unsigned long address
 
 	if (page_private(kpte_page) == 0) {
 		save_page(kpte_page);
-		revert_page(address, ref_prot);
+		revert_page(address, pfn, ref_prot);
  	}
 	return 0;
 } 
@@ -180,6 +178,7 @@ __change_page_attr(unsigned long address
  */
 int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
 {
+	unsigned long phys_base_pfn = __pa_symbol(__START_KERNEL_map) >> PAGE_SHIFT;
 	int err = 0; 
 	int i; 
 
@@ -192,10 +191,11 @@ int change_page_attr_addr(unsigned long 
 			break; 
 		/* Handle kernel mapping too which aliases part of the
 		 * lowmem */
-		if (__pa(address) < KERNEL_TEXT_SIZE) {
+		if ((pfn >= phys_base_pfn) &&
+			((pfn - phys_base_pfn) < (KERNEL_TEXT_SIZE >> PAGE_SHIFT))) {
 			unsigned long addr2;
 			pgprot_t prot2;
-			addr2 = __START_KERNEL_map + __pa(address);
+			addr2 = __START_KERNEL_map + ((pfn - phys_base_pfn) << PAGE_SHIFT);
 			/* Make sure the kernel mappings stay executable */
 			prot2 = pte_pgprot(pte_mkexec(pfn_pte(0, prot)));
 			err = __change_page_attr(addr2, pfn, prot2,
diff -puN include/asm-x86_64/page.h~x86_64-__pa-and-__pa_symbol-address-space-separation include/asm-x86_64/page.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/page.h~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/page.h	2007-03-07 01:31:03.000000000 +0530
@@ -102,17 +102,15 @@ typedef struct { unsigned long pgprot; }
 
 /* Note: __pa(&symbol_visible_to_c) should be always replaced with __pa_symbol.
    Otherwise you risk miscompilation. */ 
-#define __pa(x)			(((unsigned long)(x)>=__START_KERNEL_map)?(unsigned long)(x) - (unsigned long)__START_KERNEL_map:(unsigned long)(x) - PAGE_OFFSET)
+#define __pa(x)			((unsigned long)(x) - PAGE_OFFSET)
 /* __pa_symbol should be used for C visible symbols.
    This seems to be the official gcc blessed way to do such arithmetic. */ 
 #define __pa_symbol(x)		\
 	({unsigned long v;  \
 	  asm("" : "=r" (v) : "0" (x)); \
-	  __pa(v); })
+	  (v - __START_KERNEL_map); })
 
 #define __va(x)			((void *)((unsigned long)(x)+PAGE_OFFSET))
-#define __boot_va(x)		__va(x)
-#define __boot_pa(x)		__pa(x)
 #ifdef CONFIG_FLATMEM
 #define pfn_valid(pfn)		((pfn) < end_pfn)
 #endif
diff -puN include/asm-x86_64/pgtable.h~x86_64-__pa-and-__pa_symbol-address-space-separation include/asm-x86_64/pgtable.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/pgtable.h~x86_64-__pa-and-__pa_symbol-address-space-separation	2007-03-07 01:31:03.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/pgtable.h	2007-03-07 01:31:03.000000000 +0530
@@ -20,7 +20,7 @@ extern pmd_t level2_kernel_pgt[512];
 extern pgd_t init_level4_pgt[];
 extern unsigned long __supported_pte_mask;
 
-#define swapper_pg_dir init_level4_pgt
+#define swapper_pg_dir ((pgd_t *)NULL)
 
 extern void paging_init(void);
 extern void clear_kernel_mapping(unsigned long addr, unsigned long size);
@@ -30,7 +30,7 @@ extern void clear_kernel_mapping(unsigne
  * for zero-mapped memory areas etc..
  */
 extern unsigned long empty_zero_page[PAGE_SIZE/sizeof(unsigned long)];
-#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
+#define ZERO_PAGE(vaddr) (pfn_to_page(__pa_symbol(&empty_zero_page) >> PAGE_SHIFT))
 
 #endif /* !__ASSEMBLY__ */
 
_

[PATCH 18/20] x86_64: Relocatable Kernel Support

[Vivek Goyal]

This patch modifies the x86_64 kernel so that it can be loaded and run
at any 2M aligned address, below 512G.  The technique used is to
compile the decompressor with -fPIC and modify it so the decompressor
is fully relocatable.  For the main kernel the page tables are
modified so the kernel remains at the same virtual address.  In
addition a variable phys_base is kept that holds the physical address
the kernel is loaded at.  __pa_symbol is modified to add that when
we take the address of a kernel symbol.

When loaded with a normal bootloader the decompressor will decompress
the kernel to 2M and it will run there.  This both ensures the
relocation code is always working, and makes it easier to use 2M
pages for the kernel and the cpu.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/Kconfig                     |   50 ++++
 arch/x86_64/boot/compressed/Makefile    |   12 -
 arch/x86_64/boot/compressed/head.S      |  322 +++++++++++++++++++++++---------
 arch/x86_64/boot/compressed/misc.c      |  251 +++++++++++++-----------
 arch/x86_64/boot/compressed/vmlinux.lds |   44 ++++
 arch/x86_64/boot/compressed/vmlinux.scr |    9 
 arch/x86_64/kernel/head.S               |  225 ++++++++++++----------
 arch/x86_64/kernel/suspend_asm.S        |    7 
 include/asm-x86_64/page.h               |    6 
 9 files changed, 596 insertions(+), 330 deletions(-)

diff -puN arch/x86_64/boot/compressed/head.S~x86_64-Relocatable-kernel-support arch/x86_64/boot/compressed/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/boot/compressed/head.S~x86_64-Relocatable-kernel-support	2007-03-07 01:31:35.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/boot/compressed/head.S	2007-03-07 01:31:35.000000000 +0530
@@ -26,116 +26,262 @@
 
 #include <linux/linkage.h>
 #include <asm/segment.h>
+#include <asm/pgtable.h>
 #include <asm/page.h>
+#include <asm/msr.h>
 
+.section ".text.head"
 	.code32
 	.globl startup_32
-	
+
 startup_32:
 	cld
 	cli
-	movl $(__KERNEL_DS),%eax
-	movl %eax,%ds
-	movl %eax,%es
-	movl %eax,%fs
-	movl %eax,%gs
-
-	lss stack_start,%esp
-	xorl %eax,%eax
-1:	incl %eax		# check that A20 really IS enabled
-	movl %eax,0x000000	# loop forever if it isn't
-	cmpl %eax,0x100000
-	je 1b
+	movl	$(__KERNEL_DS), %eax
+	movl	%eax, %ds
+	movl	%eax, %es
+	movl	%eax, %ss
+
+/* Calculate the delta between where we were compiled to run
+ * at and where we were actually loaded at.  This can only be done
+ * with a short local call on x86.  Nothing  else will tell us what
+ * address we are running at.  The reserved chunk of the real-mode
+ * data at 0x34-0x3f are used as the stack for this calculation.
+ * Only 4 bytes are needed.
+ */
+	leal	0x40(%esi), %esp
+	call	1f
+1:	popl	%ebp
+	subl	$1b, %ebp
+
+/* Compute the delta between where we were compiled to run at
+ * and where the code will actually run at.
+ */
+/* %ebp contains the address we are loaded at by the boot loader and %ebx
+ * contains the address where we should move the kernel image temporarily
+ * for safe in-place decompression.
+ */
+
+#ifdef CONFIG_RELOCATABLE
+	movl	%ebp, %ebx
+	addl	$(LARGE_PAGE_SIZE -1), %ebx
+	andl	$LARGE_PAGE_MASK, %ebx
+#else
+	movl	$CONFIG_PHYSICAL_START, %ebx
+#endif
+
+	/* Replace the compressed data size with the uncompressed size */
+	subl	input_len(%ebp), %ebx
+	movl	output_len(%ebp), %eax
+	addl	%eax, %ebx
+	/* Add 8 bytes for every 32K input block */
+	shrl	$12, %eax
+	addl	%eax, %ebx
+	/* Add 32K + 18 bytes of extra slack and align on a 4K boundary */
+	addl	$(32768 + 18 + 4095), %ebx
+	andl	$~4095, %ebx
 
 /*
- * Initialize eflags.  Some BIOS's leave bits like NT set.  This would
- * confuse the debugger if this code is traced.
- * XXX - best to initialize before switching to protected mode.
+ * Prepare for entering 64 bit mode
  */
-	pushl $0
-	popfl
+
+	/* Load new GDT with the 64bit segments using 32bit descriptor */
+	leal	gdt(%ebp), %eax
+	movl	%eax, gdt+2(%ebp)
+	lgdt	gdt(%ebp)
+
+	/* Enable PAE mode */
+	xorl	%eax, %eax
+	orl	$(1 << 5), %eax
+	movl	%eax, %cr4
+
+ /*
+  * Build early 4G boot pagetable
+  */
+	/* Initialize Page tables to 0*/
+	leal	pgtable(%ebx), %edi
+	xorl	%eax, %eax
+	movl	$((4096*6)/4), %ecx
+	rep	stosl
+
+	/* Build Level 4 */
+	leal	pgtable + 0(%ebx), %edi
+	leal	0x1007 (%edi), %eax
+	movl	%eax, 0(%edi)
+
+	/* Build Level 3 */
+	leal	pgtable + 0x1000(%ebx), %edi
+	leal	0x1007(%edi), %eax
+	movl	$4, %ecx
+1:	movl	%eax, 0x00(%edi)
+	addl	$0x00001000, %eax
+	addl	$8, %edi
+	decl	%ecx
+	jnz	1b
+
+	/* Build Level 2 */
+	leal	pgtable + 0x2000(%ebx), %edi
+	movl	$0x00000183, %eax
+	movl	$2048, %ecx
+1:	movl	%eax, 0(%edi)
+	addl	$0x00200000, %eax
+	addl	$8, %edi
+	decl	%ecx
+	jnz	1b
+
+	/* Enable the boot page tables */
+	leal	pgtable(%ebx), %eax
+	movl	%eax, %cr3
+
+	/* Enable Long mode in EFER (Extended Feature Enable Register) */
+	movl	$MSR_EFER, %ecx
+	rdmsr
+	btsl	$_EFER_LME, %eax
+	wrmsr
+
+	/* Setup for the jump to 64bit mode
+	 *
+	 * When the jump is performend we will be in long mode but
+	 * in 32bit compatibility mode with EFER.LME = 1, CS.L = 0, CS.D = 1
+	 * (and in turn EFER.LMA = 1).	To jump into 64bit mode we use
+	 * the new gdt/idt that has __KERNEL_CS with CS.L = 1.
+	 * We place all of the values on our mini stack so lret can
+	 * used to perform that far jump.
+	 */
+	pushl	$__KERNEL_CS
+	leal	startup_64(%ebp), %eax
+	pushl	%eax
+
+	/* Enter paged protected Mode, activating Long Mode */
+	movl	$0x80000001, %eax /* Enable Paging and Protected mode */
+	movl	%eax, %cr0
+
+	/* Jump from 32bit compatibility mode into 64bit mode. */
+	lret
+
+	/* Be careful here startup_64 needs to be at a predictable
+	 * address so I can export it in an ELF header.  Bootloaders
+	 * should look at the ELF header to find this address, as
+	 * it may change in the future.
+	 */
+	.code64
+	.org 0x100
+ENTRY(startup_64)
+	/* We come here either from startup_32 or directly from a
+	 * 64bit bootloader.  If we come here from a bootloader we depend on
+	 * an identity mapped page table being provied that maps our
+	 * entire text+data+bss and hopefully all of memory.
+	 */
+
+	/* Setup data segments. */
+	xorl	%eax, %eax
+	movl	%eax, %ds
+	movl	%eax, %es
+	movl	%eax, %ss
+
+	/* Compute the decompressed kernel start address.  It is where
+	 * we were loaded at aligned to a 2M boundary. %rbp contains the
+	 * decompressed kernel start address.
+	 *
+	 * If it is a relocatable kernel then decompress and run the kernel
+	 * from load address aligned to 2MB addr, otherwise decompress and
+	 * run the kernel from CONFIG_PHYSICAL_START
+	 */
+
+	/* Start with the delta to where the kernel will run at. */
+#ifdef CONFIG_RELOCATABLE
+	leaq	startup_32(%rip) /* - $startup_32 */, %rbp
+	addq	$(LARGE_PAGE_SIZE - 1), %rbp
+	andq	$LARGE_PAGE_MASK, %rbp
+	movq	%rbp, %rbx
+#else
+	movq	$CONFIG_PHYSICAL_START, %rbp
+	movq	%rbp, %rbx
+#endif
+
+	/* Replace the compressed data size with the uncompressed size */
+	movl	input_len(%rip), %eax
+	subq	%rax, %rbx
+	movl	output_len(%rip), %eax
+	addq	%rax, %rbx
+	/* Add 8 bytes for every 32K input block */
+	shrq	$12, %rax
+	addq	%rax, %rbx
+	/* Add 32K + 18 bytes of extra slack and align on a 4K boundary */
+	addq	$(32768 + 18 + 4095), %rbx
+	andq	$~4095, %rbx
+
+/* Copy the compressed kernel to the end of our buffer
+ * where decompression in place becomes safe.
+ */
+	leaq	_end(%rip), %r8
+	leaq	_end(%rbx), %r9
+	movq	$_end /* - $startup_32 */, %rcx
+1:	subq	$8, %r8
+	subq	$8, %r9
+	movq	0(%r8), %rax
+	movq	%rax, 0(%r9)
+	subq	$8, %rcx
+	jnz	1b
+
+/*
+ * Jump to the relocated address.
+ */
+	leaq	relocated(%rbx), %rax
+	jmp	*%rax
+
+.section ".text"
+relocated:
+
 /*
  * Clear BSS
  */
-	xorl %eax,%eax
-	movl $_edata,%edi
-	movl $_end,%ecx
-	subl %edi,%ecx
+	xorq	%rax, %rax
+	leaq    _edata(%rbx), %rdi
+	leaq    _end(%rbx), %rcx
+	subq	%rdi, %rcx
 	cld
 	rep
 	stosb
+
+	/* Setup the stack */
+	leaq	user_stack_end(%rip), %rsp
+
+	/* zero EFLAGS after setting rsp */
+	pushq	$0
+	popfq
+
 /*
  * Do the decompression, and jump to the new kernel..
  */
-	subl $16,%esp	# place for structure on the stack
-	movl %esp,%eax
-	pushl %esi	# real mode pointer as second arg
-	pushl %eax	# address of structure as first arg
-	call decompress_kernel
-	orl  %eax,%eax 
-	jnz  3f
-	addl $8,%esp
-	xorl %ebx,%ebx
-	ljmp $(__KERNEL_CS), $__PHYSICAL_START
-
-/*
- * We come here, if we were loaded high.
- * We need to move the move-in-place routine down to 0x1000
- * and then start it with the buffer addresses in registers,
- * which we got from the stack.
- */
-3:
-	movl %esi,%ebx	
-	movl $move_routine_start,%esi
-	movl $0x1000,%edi
-	movl $move_routine_end,%ecx
-	subl %esi,%ecx
-	addl $3,%ecx
-	shrl $2,%ecx
-	cld
-	rep
-	movsl
+	pushq	%rsi			# Save the real mode argument
+	movq	%rsi, %rdi		# real mode address
+	leaq	_heap(%rip), %rsi	# _heap
+	leaq	input_data(%rip), %rdx  # input_data
+	movl	input_len(%rip), %eax
+	movq	%rax, %rcx		# input_len
+	movq	%rbp, %r8		# output
+	call	decompress_kernel
+	popq	%rsi
 
-	popl %esi	# discard the address
-	addl $4,%esp	# real mode pointer
-	popl %esi	# low_buffer_start
-	popl %ecx	# lcount
-	popl %edx	# high_buffer_start
-	popl %eax	# hcount
-	movl $__PHYSICAL_START,%edi
-	cli		# make sure we don't get interrupted
-	ljmp $(__KERNEL_CS), $0x1000 # and jump to the move routine
 
 /*
- * Routine (template) for moving the decompressed kernel in place,
- * if we were high loaded. This _must_ PIC-code !
+ * Jump to the decompressed kernel.
  */
-move_routine_start:
-	movl %ecx,%ebp
-	shrl $2,%ecx
-	rep
-	movsl
-	movl %ebp,%ecx
-	andl $3,%ecx
-	rep
-	movsb
-	movl %edx,%esi
-	movl %eax,%ecx	# NOTE: rep movsb won't move if %ecx == 0
-	addl $3,%ecx
-	shrl $2,%ecx
-	rep
-	movsl
-	movl %ebx,%esi	# Restore setup pointer
-	xorl %ebx,%ebx
-	ljmp $(__KERNEL_CS), $__PHYSICAL_START
-move_routine_end:
+	jmp	*%rbp
 
-
-/* Stack for uncompression */ 	
-	.align 32
-user_stack:	 	
+	.data
+gdt:
+	.word	gdt_end - gdt
+	.long	gdt
+	.word	0
+	.quad	0x0000000000000000	/* NULL descriptor */
+	.quad	0x00af9a000000ffff	/* __KERNEL_CS */
+	.quad	0x00cf92000000ffff	/* __KERNEL_DS */
+gdt_end:
+	.bss
+/* Stack for uncompression */
+	.balign 4
+user_stack:
 	.fill 4096,4,0
-stack_start:	
-	.long user_stack+4096
-	.word __KERNEL_DS
-
+user_stack_end:
diff -puN arch/x86_64/boot/compressed/Makefile~x86_64-Relocatable-kernel-support arch/x86_64/boot/compressed/Makefile
--- linux-2.6.21-rc2-reloc/arch/x86_64/boot/compressed/Makefile~x86_64-Relocatable-kernel-support	2007-03-07 01:31:35.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/boot/compressed/Makefile	2007-03-07 01:31:35.000000000 +0530
@@ -8,16 +8,14 @@
 
 targets		:= vmlinux vmlinux.bin vmlinux.bin.gz head.o misc.o piggy.o
 EXTRA_AFLAGS	:= -traditional
-AFLAGS		:= $(subst -m64,-m32,$(AFLAGS))
 
 # cannot use EXTRA_CFLAGS because base CFLAGS contains -mkernel which conflicts with
 # -m32
-CFLAGS := -m32 -D__KERNEL__ -Iinclude -O2  -fno-strict-aliasing
-LDFLAGS := -m elf_i386
+CFLAGS := -m64 -D__KERNEL__ -Iinclude -O2  -fno-strict-aliasing -fPIC -mcmodel=small -fno-builtin
+LDFLAGS := -m elf_x86_64
 
-LDFLAGS_vmlinux := -Ttext $(IMAGE_OFFSET) -e startup_32 -m elf_i386
-
-$(obj)/vmlinux: $(obj)/head.o $(obj)/misc.o $(obj)/piggy.o FORCE
+LDFLAGS_vmlinux := -T
+$(obj)/vmlinux: $(src)/vmlinux.lds $(obj)/head.o $(obj)/misc.o $(obj)/piggy.o FORCE
 	$(call if_changed,ld)
 	@:
 
@@ -27,7 +25,7 @@ $(obj)/vmlinux.bin: vmlinux FORCE
 $(obj)/vmlinux.bin.gz: $(obj)/vmlinux.bin FORCE
 	$(call if_changed,gzip)
 
-LDFLAGS_piggy.o := -r --format binary --oformat elf32-i386 -T
+LDFLAGS_piggy.o := -r --format binary --oformat elf64-x86-64 -T
 
 $(obj)/piggy.o: $(obj)/vmlinux.scr $(obj)/vmlinux.bin.gz FORCE
 	$(call if_changed,ld)
diff -puN arch/x86_64/boot/compressed/misc.c~x86_64-Relocatable-kernel-support arch/x86_64/boot/compressed/misc.c
--- linux-2.6.21-rc2-reloc/arch/x86_64/boot/compressed/misc.c~x86_64-Relocatable-kernel-support	2007-03-07 01:31:35.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/boot/compressed/misc.c	2007-03-07 01:31:35.000000000 +0530
@@ -9,10 +9,95 @@
  * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
  */
 
+#define _LINUX_STRING_H_ 1
+#define __LINUX_BITMAP_H 1
+
+#include <linux/linkage.h>
 #include <linux/screen_info.h>
 #include <asm/io.h>
 #include <asm/page.h>
 
+/* WARNING!!
+ * This code is compiled with -fPIC and it is relocated dynamically
+ * at run time, but no relocation processing is performed.
+ * This means that it is not safe to place pointers in static structures.
+ */
+
+/*
+ * Getting to provable safe in place decompression is hard.
+ * Worst case behaviours need to be analized.
+ * Background information:
+ *
+ * The file layout is:
+ *    magic[2]
+ *    method[1]
+ *    flags[1]
+ *    timestamp[4]
+ *    extraflags[1]
+ *    os[1]
+ *    compressed data blocks[N]
+ *    crc[4] orig_len[4]
+ *
+ * resulting in 18 bytes of non compressed data overhead.
+ *
+ * Files divided into blocks
+ * 1 bit (last block flag)
+ * 2 bits (block type)
+ *
+ * 1 block occurs every 32K -1 bytes or when there 50% compression has been achieved.
+ * The smallest block type encoding is always used.
+ *
+ * stored:
+ *    32 bits length in bytes.
+ *
+ * fixed:
+ *    magic fixed tree.
+ *    symbols.
+ *
+ * dynamic:
+ *    dynamic tree encoding.
+ *    symbols.
+ *
+ *
+ * The buffer for decompression in place is the length of the
+ * uncompressed data, plus a small amount extra to keep the algorithm safe.
+ * The compressed data is placed at the end of the buffer.  The output
+ * pointer is placed at the start of the buffer and the input pointer
+ * is placed where the compressed data starts.  Problems will occur
+ * when the output pointer overruns the input pointer.
+ *
+ * The output pointer can only overrun the input pointer if the input
+ * pointer is moving faster than the output pointer.  A condition only
+ * triggered by data whose compressed form is larger than the uncompressed
+ * form.
+ *
+ * The worst case at the block level is a growth of the compressed data
+ * of 5 bytes per 32767 bytes.
+ *
+ * The worst case internal to a compressed block is very hard to figure.
+ * The worst case can at least be boundined by having one bit that represents
+ * 32764 bytes and then all of the rest of the bytes representing the very
+ * very last byte.
+ *
+ * All of which is enough to compute an amount of extra data that is required
+ * to be safe.  To avoid problems at the block level allocating 5 extra bytes
+ * per 32767 bytes of data is sufficient.  To avoind problems internal to a block
+ * adding an extra 32767 bytes (the worst case uncompressed block size) is
+ * sufficient, to ensure that in the worst case the decompressed data for
+ * block will stop the byte before the compressed data for a block begins.
+ * To avoid problems with the compressed data's meta information an extra 18
+ * bytes are needed.  Leading to the formula:
+ *
+ * extra_bytes = (uncompressed_size >> 12) + 32768 + 18 + decompressor_size.
+ *
+ * Adding 8 bytes per 32K is a bit excessive but much easier to calculate.
+ * Adding 32768 instead of 32767 just makes for round numbers.
+ * Adding the decompressor_size is necessary as it musht live after all
+ * of the data as well.  Last I measured the decompressor is about 14K.
+ * 10K of actuall data and 4K of bss.
+ *
+ */
+
 /*
  * gzip declarations
  */
@@ -28,15 +113,20 @@ typedef unsigned char  uch;
 typedef unsigned short ush;
 typedef unsigned long  ulg;
 
-#define WSIZE 0x8000		/* Window size must be at least 32k, */
-				/* and a power of two */
-
-static uch *inbuf;	     /* input buffer */
-static uch window[WSIZE];    /* Sliding window buffer */
-
-static unsigned insize = 0;  /* valid bytes in inbuf */
-static unsigned inptr = 0;   /* index of next byte to be processed in inbuf */
-static unsigned outcnt = 0;  /* bytes in output buffer */
+#define WSIZE 0x80000000	/* Window size must be at least 32k,
+				 * and a power of two
+				 * We don't actually have a window just
+				 * a huge output buffer so I report
+				 * a 2G windows size, as that should
+				 * always be larger than our output buffer.
+				 */
+
+static uch *inbuf;	/* input buffer */
+static uch *window;	/* Sliding window buffer, (and final output buffer) */
+
+static unsigned insize;  /* valid bytes in inbuf */
+static unsigned inptr;   /* index of next byte to be processed in inbuf */
+static unsigned outcnt;  /* bytes in output buffer */
 
 /* gzip flag byte */
 #define ASCII_FLAG   0x01 /* bit 0 set: file probably ASCII text */
@@ -87,8 +177,6 @@ extern unsigned char input_data[];
 extern int input_len;
 
 static long bytes_out = 0;
-static uch *output_data;
-static unsigned long output_ptr = 0;
 
 static void *malloc(int size);
 static void free(void *where);
@@ -98,17 +186,10 @@ static void *memcpy(void *dest, const vo
 
 static void putstr(const char *);
 
-extern int end;
-static long free_mem_ptr = (long)&end;
+static long free_mem_ptr;
 static long free_mem_end_ptr;
 
-#define INPLACE_MOVE_ROUTINE  0x1000
-#define LOW_BUFFER_START      0x2000
-#define LOW_BUFFER_MAX       0x90000
-#define HEAP_SIZE             0x3000
-static unsigned int low_buffer_end, low_buffer_size;
-static int high_loaded =0;
-static uch *high_buffer_start /* = (uch *)(((ulg)&end) + HEAP_SIZE)*/;
+#define HEAP_SIZE             0x6000
 
 static char *vidmem = (char *)0xb8000;
 static int vidport;
@@ -218,58 +299,31 @@ static void* memcpy(void* dest, const vo
  */
 static int fill_inbuf(void)
 {
-	if (insize != 0) {
-		error("ran out of input data");
-	}
-
-	inbuf = input_data;
-	insize = input_len;
-	inptr = 1;
-	return inbuf[0];
+	error("ran out of input data");
+	return 0;
 }
 
 /* ===========================================================================
  * Write the output window window[0..outcnt-1] and update crc and bytes_out.
  * (Used for the decompressed data only.)
  */
-static void flush_window_low(void)
-{
-    ulg c = crc;         /* temporary variable */
-    unsigned n;
-    uch *in, *out, ch;
-    
-    in = window;
-    out = &output_data[output_ptr]; 
-    for (n = 0; n < outcnt; n++) {
-	    ch = *out++ = *in++;
-	    c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
-    }
-    crc = c;
-    bytes_out += (ulg)outcnt;
-    output_ptr += (ulg)outcnt;
-    outcnt = 0;
-}
-
-static void flush_window_high(void)
-{
-    ulg c = crc;         /* temporary variable */
-    unsigned n;
-    uch *in,  ch;
-    in = window;
-    for (n = 0; n < outcnt; n++) {
-	ch = *output_data++ = *in++;
-	if ((ulg)output_data == low_buffer_end) output_data=high_buffer_start;
-	c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
-    }
-    crc = c;
-    bytes_out += (ulg)outcnt;
-    outcnt = 0;
-}
-
 static void flush_window(void)
 {
-	if (high_loaded) flush_window_high();
-	else flush_window_low();
+	/* With my window equal to my output buffer
+	 * I only need to compute the crc here.
+	 */
+	ulg c = crc;         /* temporary variable */
+	unsigned n;
+	uch *in, ch;
+
+	in = window;
+	for (n = 0; n < outcnt; n++) {
+		ch = *in++;
+		c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
+	}
+	crc = c;
+	bytes_out += (ulg)outcnt;
+	outcnt = 0;
 }
 
 static void error(char *x)
@@ -281,57 +335,8 @@ static void error(char *x)
 	while(1);	/* Halt */
 }
 
-static void setup_normal_output_buffer(void)
-{
-#ifdef STANDARD_MEMORY_BIOS_CALL
-	if (RM_EXT_MEM_K < 1024) error("Less than 2MB of memory");
-#else
-	if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) < 1024) error("Less than 2MB of memory");
-#endif
-	output_data = (unsigned char *)__PHYSICAL_START; /* Normally Points to 1M */
-	free_mem_end_ptr = (long)real_mode;
-}
-
-struct moveparams {
-	uch *low_buffer_start;  int lcount;
-	uch *high_buffer_start; int hcount;
-};
-
-static void setup_output_buffer_if_we_run_high(struct moveparams *mv)
-{
-	high_buffer_start = (uch *)(((ulg)&end) + HEAP_SIZE);
-#ifdef STANDARD_MEMORY_BIOS_CALL
-	if (RM_EXT_MEM_K < (3*1024)) error("Less than 4MB of memory");
-#else
-	if ((RM_ALT_MEM_K > RM_EXT_MEM_K ? RM_ALT_MEM_K : RM_EXT_MEM_K) < (3*1024)) error("Less than 4MB of memory");
-#endif	
-	mv->low_buffer_start = output_data = (unsigned char *)LOW_BUFFER_START;
-	low_buffer_end = ((unsigned int)real_mode > LOW_BUFFER_MAX
-	  ? LOW_BUFFER_MAX : (unsigned int)real_mode) & ~0xfff;
-	low_buffer_size = low_buffer_end - LOW_BUFFER_START;
-	high_loaded = 1;
-	free_mem_end_ptr = (long)high_buffer_start;
-	if ( (__PHYSICAL_START + low_buffer_size) > ((ulg)high_buffer_start)) {
-		high_buffer_start = (uch *)(__PHYSICAL_START + low_buffer_size);
-		mv->hcount = 0; /* say: we need not to move high_buffer */
-	}
-	else mv->hcount = -1;
-	mv->high_buffer_start = high_buffer_start;
-}
-
-static void close_output_buffer_if_we_run_high(struct moveparams *mv)
-{
-	if (bytes_out > low_buffer_size) {
-		mv->lcount = low_buffer_size;
-		if (mv->hcount)
-			mv->hcount = bytes_out - low_buffer_size;
-	} else {
-		mv->lcount = bytes_out;
-		mv->hcount = 0;
-	}
-}
-
-int decompress_kernel(struct moveparams *mv, void *rmode)
+asmlinkage void decompress_kernel(void *rmode, unsigned long heap,
+	uch *input_data, unsigned long input_len, uch *output)
 {
 	real_mode = rmode;
 
@@ -346,13 +351,21 @@ int decompress_kernel(struct moveparams 
 	lines = RM_SCREEN_INFO.orig_video_lines;
 	cols = RM_SCREEN_INFO.orig_video_cols;
 
-	if (free_mem_ptr < 0x100000) setup_normal_output_buffer();
-	else setup_output_buffer_if_we_run_high(mv);
+	window = output;  		/* Output buffer (Normally at 1M) */
+	free_mem_ptr     = heap;	/* Heap  */
+	free_mem_end_ptr = heap + HEAP_SIZE;
+	inbuf  = input_data;		/* Input buffer */
+	insize = input_len;
+	inptr  = 0;
+
+	if ((ulg)output & 0x1fffffUL)
+		error("Destination address not 2M aligned");
+	if ((ulg)output >= 0xffffffffffUL)
+		error("Destination address too large");
 
 	makecrc();
 	putstr(".\nDecompressing Linux...");
 	gunzip();
 	putstr("done.\nBooting the kernel.\n");
-	if (high_loaded) close_output_buffer_if_we_run_high(mv);
-	return high_loaded;
+	return;
 }
diff -puN /dev/null arch/x86_64/boot/compressed/vmlinux.lds
--- /dev/null	2007-03-07 00:46:17.354096448 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/boot/compressed/vmlinux.lds	2007-03-07 01:31:35.000000000 +0530
@@ -0,0 +1,44 @@
+OUTPUT_FORMAT("elf64-x86-64", "elf64-x86-64", "elf64-x86-64")
+OUTPUT_ARCH(i386:x86-64)
+ENTRY(startup_64)
+SECTIONS
+{
+	/* Be careful parts of head.S assume startup_32 is at
+ 	 * address 0.
+	 */
+	. = 0;
+	.text :	{
+		_head = . ;
+		*(.text.head)
+		_ehead = . ;
+		*(.text.compressed)
+		_text = .; 	/* Text */
+		*(.text)
+		*(.text.*)
+		_etext = . ;
+	}
+	.rodata : {
+		_rodata = . ;
+		*(.rodata)	 /* read-only data */
+		*(.rodata.*)
+		_erodata = . ;
+	}
+	.data :	{
+		_data = . ;
+		*(.data)
+		*(.data.*)
+		_edata = . ;
+	}
+	.bss : {
+		_bss = . ;
+		*(.bss)
+		*(.bss.*)
+		*(COMMON)
+		. = ALIGN(8);
+		_end = . ;
+		. = ALIGN(4096);
+		pgtable = . ;
+		. = . + 4096 * 6;
+		_heap = .;
+	}
+}
diff -puN arch/x86_64/boot/compressed/vmlinux.scr~x86_64-Relocatable-kernel-support arch/x86_64/boot/compressed/vmlinux.scr
--- linux-2.6.21-rc2-reloc/arch/x86_64/boot/compressed/vmlinux.scr~x86_64-Relocatable-kernel-support	2007-03-07 01:31:35.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/boot/compressed/vmlinux.scr	2007-03-07 01:31:35.000000000 +0530
@@ -1,9 +1,10 @@
 SECTIONS
 {
-  .data : { 
+  .text.compressed : {
 	input_len = .;
-	LONG(input_data_end - input_data) input_data = .; 
-	*(.data) 
-	input_data_end = .; 
+	LONG(input_data_end - input_data) input_data = .;
+	*(.data)
+	output_len = . - 4;
+	input_data_end = .;
 	}
 }
diff -puN arch/x86_64/Kconfig~x86_64-Relocatable-kernel-support arch/x86_64/Kconfig
--- linux-2.6.21-rc2-reloc/arch/x86_64/Kconfig~x86_64-Relocatable-kernel-support	2007-03-07 01:31:35.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/Kconfig	2007-03-07 01:31:35.000000000 +0530
@@ -565,23 +565,57 @@ config CRASH_DUMP
 	  PHYSICAL_START.
           For more details see Documentation/kdump/kdump.txt
 
+config RELOCATABLE
+	bool "Build a relocatable kernel(EXPERIMENTAL)"
+	depends on EXPERIMENTAL
+	default y
+	help
+	  Builds a relocatable kernel. This enables loading and running
+	  a kernel binary from a different physical address than it has
+	  been compiled for.
+ 
+	  One use is for the kexec on panic case where the recovery kernel
+	  must live at a different physical address than the primary
+	  kernel.
+
+	  Note: If CONFIG_RELOCATABLE=y, then kernel run from the address
+	  it has been loaded at and compile time physical address
+	  (CONFIG_PHYSICAL_START) is ignored.
+
 config PHYSICAL_START
 	hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
-	default "0x1000000" if CRASH_DUMP
 	default "0x200000"
 	help
-	  This gives the physical address where the kernel is loaded. Normally
-	  for regular kernels this value is 0x200000 (2MB). But in the case
-	  of kexec on panic the fail safe kernel needs to run at a different
-	  address than the panic-ed kernel. This option is used to set the load
-	  address for kernels used to capture crash dump on being kexec'ed
-	  after panic. The default value for crash dump kernels is
-	  0x1000000 (16MB). This can also be set based on the "X" value as
+	  This gives the physical address where the kernel is loaded. It
+	  should be aligned to 2MB boundary.
+
+	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
+	  bzImage will decompress itself to above physical address and
+	  run from there. Otherwise, bzImage will run from the address where
+	  it has been loaded by the boot loader and will ignore above physical
+	  address.
+
+	  In normal kdump cases one does not have to set/change this option
+	  as now bzImage can be compiled as a completely relocatable image
+	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
+	  address. This option is mainly useful for the folks who don't want
+	  to use a bzImage for capturing the crash dump and want to use a
+	  vmlinux instead.
+
+	  So if you are using bzImage for capturing the crash dump, leave
+	  the value here unchanged to 0x200000 and set CONFIG_RELOCATABLE=y.
+	  Otherwise if you plan to use vmlinux for capturing the crash dump
+	  change this value to start of the reserved region (Typically 16MB
+	  0x1000000). In other words, it can be set based on the "X" value as
 	  specified in the "crashkernel=YM@XM" command line boot parameter
 	  passed to the panic-ed kernel. Typically this parameter is set as
 	  crashkernel=64M@16M. Please take a look at
 	  Documentation/kdump/kdump.txt for more details about crash dumps.
 
+	  Usage of bzImage for capturing the crash dump is advantageous as
+	  one does not have to build two kernels. Same kernel can be used
+	  as production kernel and capture kernel.
+
 	  Don't change this unless you know what you are doing.
 
 config SECCOMP
diff -puN arch/x86_64/kernel/head.S~x86_64-Relocatable-kernel-support arch/x86_64/kernel/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/head.S~x86_64-Relocatable-kernel-support	2007-03-07 01:31:35.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/head.S	2007-03-07 01:31:35.000000000 +0530
@@ -5,6 +5,7 @@
  *  Copyright (C) 2000 Pavel Machek <pavel@suse.cz>
  *  Copyright (C) 2000 Karsten Keil <kkeil@suse.de>
  *  Copyright (C) 2001,2002 Andi Kleen <ak@suse.de>
+ *  Copyright (C) 2005 Eric Biederman <ebiederm@xmission.com>
  */
 
 
@@ -17,95 +18,127 @@
 #include <asm/page.h>
 #include <asm/msr.h>
 #include <asm/cache.h>
-	
+
 /* we are not able to switch in one step to the final KERNEL ADRESS SPACE
- * because we need identity-mapped pages on setup so define __START_KERNEL to
- * 0x100000 for this stage
- * 
+ * because we need identity-mapped pages.
+ *
  */
 
 	.text
 	.section .bootstrap.text
-	.code32
-	.globl startup_32
-/* %bx:	 1 if coming from smp trampoline on secondary cpu */ 
-startup_32:
-	
+	.code64
+	.globl startup_64
+startup_64:
+
 	/*
-	 * At this point the CPU runs in 32bit protected mode (CS.D = 1) with
-	 * paging disabled and the point of this file is to switch to 64bit
-	 * long mode with a kernel mapping for kerneland to jump into the
-	 * kernel virtual addresses.
- 	 * There is no stack until we set one up.
+	 * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 1,
+	 * and someone has loaded an identity mapped page table
+	 * for us.  These identity mapped page tables map all of the
+	 * kernel pages and possibly all of memory.
+	 *
+	 * %esi holds a physical pointer to real_mode_data.
+	 *
+	 * We come here either directly from a 64bit bootloader, or from
+	 * arch/x86_64/boot/compressed/head.S.
+	 *
+	 * We only come here initially at boot nothing else comes here.
+	 *
+	 * Since we may be loaded at an address different from what we were
+	 * compiled to run at we first fixup the physical addresses in our page
+	 * tables and then reload them.
 	 */
 
-	/* Initialize the %ds segment register */
-	movl $__KERNEL_DS,%eax
-	movl %eax,%ds
+	/* Compute the delta between the address I am compiled to run at and the
+	 * address I am actually running at.
+	 */
+	leaq	_text(%rip), %rbp
+	subq	$_text - __START_KERNEL_map, %rbp
 
-	/* Load new GDT with the 64bit segments using 32bit descriptor */
-	lgdt	pGDT32 - __START_KERNEL_map
+	/* Is the address not 2M aligned? */
+	movq	%rbp, %rax
+	andl	$~LARGE_PAGE_MASK, %eax
+	testl	%eax, %eax
+	jnz	bad_address
+
+	/* Is the address too large? */
+	leaq	_text(%rip), %rdx
+	movq	$PGDIR_SIZE, %rax
+	cmpq	%rax, %rdx
+	jae	bad_address
 
-	/* If the CPU doesn't support CPUID this will double fault.
-	 * Unfortunately it is hard to check for CPUID without a stack. 
+	/* Fixup the physical addresses in the page table
 	 */
-	
-	/* Check if extended functions are implemented */		
-	movl	$0x80000000, %eax
-	cpuid
-	cmpl	$0x80000000, %eax
-	jbe	no_long_mode
-	/* Check if long mode is implemented */
-	mov	$0x80000001, %eax
-	cpuid
-	btl	$29, %edx
-	jnc	no_long_mode
+	addq	%rbp, init_level4_pgt + 0(%rip)
+	addq	%rbp, init_level4_pgt + (258*8)(%rip)
+	addq	%rbp, init_level4_pgt + (511*8)(%rip)
+
+	addq	%rbp, level3_ident_pgt + 0(%rip)
+	addq	%rbp, level3_kernel_pgt + (510*8)(%rip)
+
+	/* Add an Identity mapping if I am above 1G */
+	leaq	_text(%rip), %rdi
+	andq	$LARGE_PAGE_MASK, %rdi
+
+	movq	%rdi, %rax
+	shrq	$PUD_SHIFT, %rax
+	andq	$(PTRS_PER_PUD - 1), %rax
+	jz	ident_complete
+
+	leaq	(level2_spare_pgt - __START_KERNEL_map + _KERNPG_TABLE)(%rbp), %rdx
+	leaq	level3_ident_pgt(%rip), %rbx
+	movq	%rdx, 0(%rbx, %rax, 8)
+
+	movq	%rdi, %rax
+	shrq	$PMD_SHIFT, %rax
+	andq	$(PTRS_PER_PMD - 1), %rax
+	leaq	__PAGE_KERNEL_LARGE_EXEC(%rdi), %rdx
+	leaq	level2_spare_pgt(%rip), %rbx
+	movq	%rdx, 0(%rbx, %rax, 8)
+ident_complete:
 
-	/*
-	 * Prepare for entering 64bits mode
+	/* Fixup the kernel text+data virtual addresses
 	 */
+	leaq	level2_kernel_pgt(%rip), %rdi
+	leaq	4096(%rdi), %r8
+	/* See if it is a valid page table entry */
+1:	testq	$1, 0(%rdi)
+	jz	2f
+	addq	%rbp, 0(%rdi)
+	/* Go to the next page */
+2:	addq	$8, %rdi
+	cmp	%r8, %rdi
+	jne	1b
 
-	/* Enable PAE mode */
-	xorl	%eax, %eax
-	btsl	$5, %eax
-	movl	%eax, %cr4
-
-	/* Setup early boot stage 4 level pagetables */
-	movl	$(init_level4_pgt - __START_KERNEL_map), %eax
-	movl	%eax, %cr3
+	/* Fixup phys_base */
+	addq	%rbp, phys_base(%rip)
 
-	/* Setup EFER (Extended Feature Enable Register) */
-	movl	$MSR_EFER, %ecx
-	rdmsr
-
-	/* Enable Long Mode */
-	btsl	$_EFER_LME, %eax
-				
-	/* Make changes effective */
-	wrmsr
+#ifdef CONFIG_SMP
+	addq	%rbp, trampoline_level4_pgt + 0(%rip)
+	addq	%rbp, trampoline_level4_pgt + (511*8)(%rip)
+#endif
+#ifdef CONFIG_ACPI_SLEEP
+	addq	%rbp, wakeup_level4_pgt + 0(%rip)
+	addq	%rbp, wakeup_level4_pgt + (511*8)(%rip)
+#endif
 
-	xorl	%eax, %eax
-	btsl	$31, %eax			/* Enable paging and in turn activate Long Mode */
-	btsl	$0, %eax			/* Enable protected mode */
-	/* Make changes effective */
-	movl	%eax, %cr0
-	/*
-	 * At this point we're in long mode but in 32bit compatibility mode
-	 * with EFER.LME = 1, CS.L = 0, CS.D = 1 (and in turn
-	 * EFER.LMA = 1). Now we want to jump in 64bit mode, to do that we use
-	 * the new gdt/idt that has __KERNEL_CS with CS.L = 1.
+	/* Due to ENTRY(), sometimes the empty space gets filled with
+	 * zeros. Better take a jmp than relying on empty space being
+	 * filled with 0x90 (nop)
 	 */
-	ljmp	$__KERNEL_CS, $(startup_64 - __START_KERNEL_map)
-
-	.code64
-	.org 0x100	
-	.globl startup_64
-startup_64:
+	jmp secondary_startup_64
 ENTRY(secondary_startup_64)
-	/* We come here either from startup_32
-	 * or directly from a 64bit bootloader.
-	 * Since we may have come directly from a bootloader we
-	 * reload the page tables here.
+	/*
+	 * At this point the CPU runs in 64bit mode CS.L = 1 CS.D = 1,
+	 * and someone has loaded a mapped page table.
+	 *
+	 * %esi holds a physical pointer to real_mode_data.
+	 *
+	 * We come here either from startup_64 (using physical addresses)
+	 * or from trampoline.S (using virtual addresses).
+	 *
+	 * Using virtual addresses from trampoline.S removes the need
+	 * to have any identity mapped pages in the kernel page table
+	 * after the boot processor executes this code.
 	 */
 
 	/* Enable PAE mode and PGE */
@@ -116,8 +149,14 @@ ENTRY(secondary_startup_64)
 
 	/* Setup early boot stage 4 level pagetables. */
 	movq	$(init_level4_pgt - __START_KERNEL_map), %rax
+	addq	phys_base(%rip), %rax
 	movq	%rax, %cr3
 
+	/* Ensure I am executing from virtual addresses */
+	movq	$1f, %rax
+	jmp	*%rax
+1:
+
 	/* Check if nx is implemented */
 	movl	$0x80000001, %eax
 	cpuid
@@ -126,17 +165,11 @@ ENTRY(secondary_startup_64)
 	/* Setup EFER (Extended Feature Enable Register) */
 	movl	$MSR_EFER, %ecx
 	rdmsr
-
-	/* Enable System Call */
-	btsl	$_EFER_SCE, %eax
-
-	/* No Execute supported? */
-	btl	$20,%edi
+	btsl	$_EFER_SCE, %eax	/* Enable System Call */
+	btl	$20,%edi		/* No Execute supported? */
 	jnc     1f
 	btsl	$_EFER_NX, %eax
-1:
-	/* Make changes effective */
-	wrmsr
+1:	wrmsr				/* Make changes effective */
 
 	/* Setup cr0 */
 #define CR0_PM				1		/* protected mode */
@@ -163,7 +196,7 @@ ENTRY(secondary_startup_64)
 	 * addresses where we're currently running on. We have to do that here
 	 * because in 32bit we couldn't load a 64bit linear address.
 	 */
-	lgdt	cpu_gdt_descr
+	lgdt	cpu_gdt_descr(%rip)
 
 	/* set up data segments. actually 0 would do too */
 	movl $__KERNEL_DS,%eax
@@ -214,6 +247,9 @@ initial_code:
 init_rsp:
 	.quad  init_thread_union+THREAD_SIZE-8
 
+bad_address:
+	jmp bad_address
+
 ENTRY(early_idt_handler)
 	cmpl $2,early_recursion_flag(%rip)
 	jz  1f
@@ -242,23 +278,7 @@ early_idt_msg:
 early_idt_ripmsg:
 	.asciz "RIP %s\n"
 
-.code32
-ENTRY(no_long_mode)
-	/* This isn't an x86-64 CPU so hang */
-1:
-	jmp	1b
-
-.org 0xf00
-	.globl pGDT32
-pGDT32:
-	.word	gdt_end-cpu_gdt_table-1
-	.long	cpu_gdt_table-__START_KERNEL_map
-
-.org 0xf10	
-ljumpvector:
-	.long	startup_64-__START_KERNEL_map
-	.word	__KERNEL_CS
-
+.balign PAGE_SIZE
 ENTRY(stext)
 ENTRY(_stext)
 
@@ -303,7 +323,7 @@ NEXT_PAGE(level2_ident_pgt)
 	 * Don't set NX because code runs from these pages.
 	 */
 	PMDS(0x0000000000000000, __PAGE_KERNEL_LARGE_EXEC, PTRS_PER_PMD)
-	
+
 NEXT_PAGE(level2_kernel_pgt)
 	/* 40MB kernel mapping. The kernel code cannot be bigger than that.
 	   When you change this change KERNEL_TEXT_SIZE in page.h too. */
@@ -313,6 +333,9 @@ NEXT_PAGE(level2_kernel_pgt)
 	/* Module mapping starts here */
 	.fill	(PTRS_PER_PMD - (KERNEL_TEXT_SIZE/PMD_SIZE)),8,0
 
+NEXT_PAGE(level2_spare_pgt)
+	.fill   512,8,0
+
 #undef PMDS
 #undef NEXT_PAGE
 
@@ -330,6 +353,10 @@ gdt:
 	.endr
 #endif
 
+ENTRY(phys_base)
+	/* This must match the first entry in level2_kernel_pgt */
+	.quad   0x0000000000000000
+
 /* We need valid kernel segments for data and code in long mode too
  * IRET will check the segment types  kkeil 2000/10/28
  * Also sysret mandates a special GDT layout 
diff -puN arch/x86_64/kernel/suspend_asm.S~x86_64-Relocatable-kernel-support arch/x86_64/kernel/suspend_asm.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/suspend_asm.S~x86_64-Relocatable-kernel-support	2007-03-07 01:31:35.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/suspend_asm.S	2007-03-07 01:31:35.000000000 +0530
@@ -71,9 +71,10 @@ loop:
 	jmp	loop
 done:
 	/* go back to the original page tables */
-	leaq	init_level4_pgt(%rip), %rax
-	subq	$__START_KERNEL_map, %rax
-	movq	%rax, %cr3
+	movq    $(init_level4_pgt - __START_KERNEL_map), %rax
+	addq    phys_base(%rip), %rax
+	movq    %rax, %cr3
+
 	/* Flush TLB, including "global" things (vmalloc) */
 	movq	mmu_cr4_features(%rip), %rax
 	movq	%rax, %rdx
diff -puN include/asm-x86_64/page.h~x86_64-Relocatable-kernel-support include/asm-x86_64/page.h
--- linux-2.6.21-rc2-reloc/include/asm-x86_64/page.h~x86_64-Relocatable-kernel-support	2007-03-07 01:31:35.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/include/asm-x86_64/page.h	2007-03-07 01:31:35.000000000 +0530
@@ -61,6 +61,8 @@ typedef struct { unsigned long pgd; } pg
 
 typedef struct { unsigned long pgprot; } pgprot_t;
 
+extern unsigned long phys_base;
+
 #define pte_val(x)	((x).pte)
 #define pmd_val(x)	((x).pmd)
 #define pud_val(x)	((x).pud)
@@ -101,14 +103,14 @@ typedef struct { unsigned long pgprot; }
 #define PAGE_OFFSET		__PAGE_OFFSET
 
 /* Note: __pa(&symbol_visible_to_c) should be always replaced with __pa_symbol.
-   Otherwise you risk miscompilation. */ 
+   Otherwise you risk miscompilation. */
 #define __pa(x)			((unsigned long)(x) - PAGE_OFFSET)
 /* __pa_symbol should be used for C visible symbols.
    This seems to be the official gcc blessed way to do such arithmetic. */ 
 #define __pa_symbol(x)		\
 	({unsigned long v;  \
 	  asm("" : "=r" (v) : "0" (x)); \
-	  (v - __START_KERNEL_map); })
+	  ((v - __START_KERNEL_map) + phys_base); })
 
 #define __va(x)			((void *)((unsigned long)(x)+PAGE_OFFSET))
 #ifdef CONFIG_FLATMEM
_

[PATCH 19/20] x86_64: Extend bzImage protocol for relocatable bzImage

[Vivek Goyal]

o Extend the bzImage protocol (same as i386) to allow bzImage loaders to
  load the protected mode kernel at non-1MB address. Now protected mode
  component is relocatable and can be loaded at non-1MB addresses.

o As of today kdump uses it to run a second kernel from a reserved memory
  area.

Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/boot/setup.S |   13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff -puN arch/x86_64/boot/setup.S~x86_64-extend-bzImage-protocol-for-relocatable-bzImage arch/x86_64/boot/setup.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/boot/setup.S~x86_64-extend-bzImage-protocol-for-relocatable-bzImage	2007-03-07 01:32:01.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/boot/setup.S	2007-03-07 01:32:01.000000000 +0530
@@ -80,7 +80,7 @@ start:
 # This is the setup header, and it must start at %cs:2 (old 0x9020:2)
 
 		.ascii	"HdrS"		# header signature
-		.word	0x0204		# header version number (>= 0x0105)
+		.word	0x0205		# header version number (>= 0x0105)
 					# or else old loadlin-1.5 will fail)
 realmode_swtch:	.word	0, 0		# default_switch, SETUPSEG
 start_sys_seg:	.word	SYSSEG
@@ -155,7 +155,16 @@ cmd_line_ptr:	.long 0			# (Header versio
 					# low memory 0x10000 or higher.
 
 ramdisk_max:	.long 0xffffffff
-	
+kernel_alignment:  .long 0x200000       # physical addr alignment required for
+					# protected mode relocatable kernel
+#ifdef CONFIG_RELOCATABLE
+relocatable_kernel:    .byte 1
+#else
+relocatable_kernel:    .byte 0
+#endif
+pad2:                  .byte 0
+pad3:                  .word 0
+
 trampoline:	call	start_of_setup
 		.align 16
 					# The offset at this point is 0x240
_

[PATCH 20/20] x86_64: Move cpu verification code to common file

[Vivek Goyal]

o This patch moves the code to verify long mode and SSE to a common file.
  This code is now shared by trampoline.S, wakeup.S, boot/setup.S and
  boot/compressed/head.S

o So far we used to do very limited check in trampoline.S, wakeup.S and
  in 32bit entry point. Now all the entry paths are forced to do the
  exhaustive check, including SSE because verify_cpu is shared.

o I am keeping this patch as last in the x86 relocatable series because
  previous patches have got quite some amount of testing done and don't want
  to distrub that. So that if there is problem introduced by this patch, at
  least it can be easily isolated.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Vivek Goyal <vgoyal@in.ibm.com>
---

 arch/x86_64/boot/compressed/head.S |   19 ++++++
 arch/x86_64/boot/setup.S           |   65 ++-------------------
 arch/x86_64/kernel/acpi/wakeup.S   |   30 +++++-----
 arch/x86_64/kernel/trampoline.S    |   51 +----------------
 arch/x86_64/kernel/verify_cpu.S    |  110 +++++++++++++++++++++++++++++++++++++
 5 files changed, 152 insertions(+), 123 deletions(-)

diff -puN arch/x86_64/boot/compressed/head.S~x86_64-move-cpu-verfication-code-to-common-file arch/x86_64/boot/compressed/head.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/boot/compressed/head.S~x86_64-move-cpu-verfication-code-to-common-file	2007-03-07 01:32:27.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/boot/compressed/head.S	2007-03-07 01:32:27.000000000 +0530
@@ -54,6 +54,15 @@ startup_32:
 1:	popl	%ebp
 	subl	$1b, %ebp
 
+/* setup a stack and make sure cpu supports long mode. */
+	movl	$user_stack_end, %eax
+	addl	%ebp, %eax
+	movl	%eax, %esp
+
+	call	verify_cpu
+	testl	%eax, %eax
+	jnz	no_longmode
+
 /* Compute the delta between where we were compiled to run at
  * and where the code will actually run at.
  */
@@ -159,13 +168,21 @@ startup_32:
 	/* Jump from 32bit compatibility mode into 64bit mode. */
 	lret
 
+no_longmode:
+	/* This isn't an x86-64 CPU so hang */
+1:
+	hlt
+	jmp     1b
+
+#include "../../kernel/verify_cpu.S"
+
 	/* Be careful here startup_64 needs to be at a predictable
 	 * address so I can export it in an ELF header.  Bootloaders
 	 * should look at the ELF header to find this address, as
 	 * it may change in the future.
 	 */
 	.code64
-	.org 0x100
+	.org 0x200
 ENTRY(startup_64)
 	/* We come here either from startup_32 or directly from a
 	 * 64bit bootloader.  If we come here from a bootloader we depend on
diff -puN arch/x86_64/boot/setup.S~x86_64-move-cpu-verfication-code-to-common-file arch/x86_64/boot/setup.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/boot/setup.S~x86_64-move-cpu-verfication-code-to-common-file	2007-03-07 01:32:27.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/boot/setup.S	2007-03-07 01:32:27.000000000 +0530
@@ -299,64 +299,10 @@ loader_ok:
 	movw	%cs,%ax
 	movw	%ax,%ds
 	
-	/* minimum CPUID flags for x86-64 */
-	/* see http://www.x86-64.org/lists/discuss/msg02971.html */		
-#define SSE_MASK ((1<<25)|(1<<26))
-#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\
-					   (1<<13)|(1<<15)|(1<<24))
-#define REQUIRED_MASK2 (1<<29)
-
-	pushfl				/* standard way to check for cpuid */
-	popl	%eax
-	movl	%eax,%ebx
-	xorl	$0x200000,%eax
-	pushl	%eax
-	popfl
-	pushfl
-	popl	%eax
-	cmpl	%eax,%ebx
-	jz	no_longmode		/* cpu has no cpuid */
-	movl	$0x0,%eax
-	cpuid
-	cmpl	$0x1,%eax
-	jb	no_longmode		/* no cpuid 1 */
-	xor	%di,%di
-	cmpl	$0x68747541,%ebx	/* AuthenticAMD */
-	jnz	noamd
-	cmpl	$0x69746e65,%edx
-	jnz	noamd
-	cmpl	$0x444d4163,%ecx
-	jnz	noamd
-	mov	$1,%di			/* cpu is from AMD */
-noamd:		
-	movl    $0x1,%eax
-	cpuid
-	andl	$REQUIRED_MASK1,%edx
-	xorl	$REQUIRED_MASK1,%edx
-	jnz	no_longmode
-	movl    $0x80000000,%eax
-	cpuid
-	cmpl    $0x80000001,%eax
-	jb      no_longmode             /* no extended cpuid */
-	movl    $0x80000001,%eax
-	cpuid
-	andl    $REQUIRED_MASK2,%edx
-	xorl    $REQUIRED_MASK2,%edx
-	jnz     no_longmode
-sse_test:		
-	movl	$1,%eax
-	cpuid
-	andl	$SSE_MASK,%edx
-	cmpl	$SSE_MASK,%edx
-	je	sse_ok
-	test	%di,%di
-	jz	no_longmode	/* only try to force SSE on AMD */ 
-	movl	$0xc0010015,%ecx	/* HWCR */
-	rdmsr
-	btr	$15,%eax	/* enable SSE */
-	wrmsr
-	xor	%di,%di		/* don't loop */
-	jmp	sse_test	/* try again */	
+	call verify_cpu
+	testl %eax,%eax
+	jz sse_ok
+
 no_longmode:
 	call	beep
 	lea	long_mode_panic,%si
@@ -366,7 +312,8 @@ no_longmode_loop:		
 long_mode_panic:
 	.string "Your CPU does not support long mode. Use a 32bit distribution."
 	.byte 0
-	
+
+#include "../kernel/verify_cpu.S"
 sse_ok:
 	popw	%ds
 	
diff -puN arch/x86_64/kernel/acpi/wakeup.S~x86_64-move-cpu-verfication-code-to-common-file arch/x86_64/kernel/acpi/wakeup.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/acpi/wakeup.S~x86_64-move-cpu-verfication-code-to-common-file	2007-03-07 01:32:27.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/acpi/wakeup.S	2007-03-07 01:32:27.000000000 +0530
@@ -43,6 +43,11 @@ wakeup_code:
 	cmpl	$0x12345678, %eax
 	jne	bogus_real_magic
 
+  	call	verify_cpu			# Verify the cpu supports long
+						# mode
+	testl	%eax, %eax
+	jnz	no_longmode
+
 	testl	$1, video_flags - wakeup_code
 	jz	1f
 	lcall   $0xc000,$3
@@ -92,18 +97,6 @@ wakeup_32:
 # Running in this code, but at low address; paging is not yet turned on.
 	movb	$0xa5, %al	;  outb %al, $0x80
 
-	/* Check if extended functions are implemented */		
-	movl	$0x80000000, %eax
-	cpuid
-	cmpl	$0x80000000, %eax
-	jbe	bogus_cpu
-	wbinvd
-	mov	$0x80000001, %eax
-	cpuid
-	btl	$29, %edx
-	jnc	bogus_cpu
-	movl	%edx,%edi
-	
 	movl	$__KERNEL_DS, %eax
 	movl	%eax, %ds
 
@@ -123,6 +116,11 @@ wakeup_32:
 	leal    (wakeup_level4_pgt - wakeup_code)(%esi), %eax
 	movl	%eax, %cr3
 
+        /* Check if nx is implemented */
+        movl    $0x80000001, %eax
+        cpuid
+        movl    %edx,%edi
+
 	/* Enable Long Mode */
 	xorl    %eax, %eax
 	btsl	$_EFER_LME, %eax
@@ -244,10 +242,12 @@ bogus_64_magic:
 	movb	$0xb3,%al	;  outb %al,$0x80
 	jmp bogus_64_magic
 
-bogus_cpu:
-	movb	$0xbc,%al	;  outb %al,$0x80
-	jmp bogus_cpu
+.code16
+no_longmode:
+	movb    $0xbc,%al       ;  outb %al,$0x80
+	jmp no_longmode
 
+#include "../verify_cpu.S"
 	
 /* This code uses an extended set of video mode numbers. These include:
  * Aliases for standard modes
diff -puN arch/x86_64/kernel/trampoline.S~x86_64-move-cpu-verfication-code-to-common-file arch/x86_64/kernel/trampoline.S
--- linux-2.6.21-rc2-reloc/arch/x86_64/kernel/trampoline.S~x86_64-move-cpu-verfication-code-to-common-file	2007-03-07 01:32:27.000000000 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/trampoline.S	2007-03-07 01:32:27.000000000 +0530
@@ -54,6 +54,8 @@ r_base = .
 	movw	$(trampoline_stack_end - r_base), %sp
 
 	call	verify_cpu		# Verify the cpu supports long mode
+	testl   %eax, %eax		# Check for return code
+	jnz	no_longmode
 
 	mov	%cs, %ax
 	movzx	%ax, %esi		# Find the 32bit trampoline location
@@ -121,57 +123,10 @@ startup_64:
 	jmp	*%rax
 
 	.code16
-verify_cpu:
-	pushl	$0			# Kill any dangerous flags
-	popfl
-
-	/* minimum CPUID flags for x86-64 */
-	/* see http://www.x86-64.org/lists/discuss/msg02971.html */
-#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\
-			   (1<<13)|(1<<15)|(1<<24)|(1<<25)|(1<<26))
-#define REQUIRED_MASK2 (1<<29)
-
-	pushfl				# check for cpuid
-	popl	%eax
-	movl	%eax, %ebx
-	xorl	$0x200000,%eax
-	pushl	%eax
-	popfl
-	pushfl
-	popl	%eax
-	pushl	%ebx
-	popfl
-	cmpl	%eax, %ebx
-	jz	no_longmode
-
-	xorl	%eax, %eax		# See if cpuid 1 is implemented
-	cpuid
-	cmpl	$0x1, %eax
-	jb	no_longmode
-
-	movl	$0x01, %eax		# Does the cpu have what it takes?
-	cpuid
-	andl	$REQUIRED_MASK1, %edx
-	xorl	$REQUIRED_MASK1, %edx
-	jnz	no_longmode
-
-	movl	$0x80000000, %eax	# See if extended cpuid is implemented
-	cpuid
-	cmpl	$0x80000001, %eax
-	jb	no_longmode
-
-	movl	$0x80000001, %eax	# Does the cpu have what it takes?
-	cpuid
-	andl	$REQUIRED_MASK2, %edx
-	xorl	$REQUIRED_MASK2, %edx
-	jnz	no_longmode
-
-	ret				# The cpu supports long mode
-
 no_longmode:
 	hlt
 	jmp no_longmode
-
+#include "verify_cpu.S"
 
 	# Careful these need to be in the same 64K segment as the above;
 tidt:
diff -puN /dev/null arch/x86_64/kernel/verify_cpu.S
--- /dev/null	2007-03-07 00:46:17.354096448 +0530
+++ linux-2.6.21-rc2-reloc-root/arch/x86_64/kernel/verify_cpu.S	2007-03-07 01:43:04.000000000 +0530
@@ -0,0 +1,110 @@
+/*
+ *
+ *	verify_cpu.S - Code for cpu long mode and SSE verification. This
+ *	code has been borrowed from boot/setup.S and was introduced by
+ * 	Andi Kleen.
+ *
+ *	Copyright (c) 2007  Andi Kleen (ak@suse.de)
+ *	Copyright (c) 2007  Eric Biederman (ebiederm@xmission.com)
+ *	Copyright (c) 2007  Vivek Goyal (vgoyal@in.ibm.com)
+ *
+ * 	This source code is licensed under the GNU General Public License,
+ * 	Version 2.  See the file COPYING for more details.
+ *
+ *	This is a common code for verification whether CPU supports
+ * 	long mode and SSE or not. It is not called directly instead this
+ *	file is included at various places and compiled in that context.
+ * 	Following are the current usage.
+ *
+ * 	This file is included by both 16bit and 32bit code.
+ *
+ *	arch/x86_64/boot/setup.S : Boot cpu verification (16bit)
+ *	arch/x86_64/boot/compressed/head.S: Boot cpu verification (32bit)
+ *	arch/x86_64/kernel/trampoline.S: secondary processor verfication (16bit)
+ *	arch/x86_64/kernel/acpi/wakeup.S:Verfication at resume (16bit)
+ *
+ *	verify_cpu, returns the status of cpu check in register %eax.
+ *		0: Success    1: Failure
+ *
+ * 	The caller needs to check for the error code and take the action
+ * 	appropriately. Either display a message or halt.
+ */
+
+verify_cpu:
+
+	pushfl				# Save caller passed flags
+	pushl	$0			# Kill any dangerous flags
+	popfl
+
+	/* minimum CPUID flags for x86-64 */
+	/* see http://www.x86-64.org/lists/discuss/msg02971.html */
+#define SSE_MASK ((1<<25)|(1<<26))
+#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\
+					   (1<<13)|(1<<15)|(1<<24))
+#define REQUIRED_MASK2 (1<<29)
+	pushfl				# standard way to check for cpuid
+	popl	%eax
+	movl	%eax,%ebx
+	xorl	$0x200000,%eax
+	pushl	%eax
+	popfl
+	pushfl
+	popl	%eax
+	cmpl	%eax,%ebx
+	jz	verify_cpu_no_longmode	# cpu has no cpuid
+
+	movl	$0x0,%eax		# See if cpuid 1 is implemented
+	cpuid
+	cmpl	$0x1,%eax
+	jb	verify_cpu_no_longmode	# no cpuid 1
+
+	xor	%di,%di
+	cmpl	$0x68747541,%ebx	# AuthenticAMD
+	jnz	verify_cpu_noamd
+	cmpl	$0x69746e65,%edx
+	jnz	verify_cpu_noamd
+	cmpl	$0x444d4163,%ecx
+	jnz	verify_cpu_noamd
+	mov	$1,%di			# cpu is from AMD
+
+verify_cpu_noamd:
+	movl    $0x1,%eax		# Does the cpu have what it takes
+	cpuid
+	andl	$REQUIRED_MASK1,%edx
+	xorl	$REQUIRED_MASK1,%edx
+	jnz	verify_cpu_no_longmode
+
+	movl    $0x80000000,%eax	# See if extended cpuid is implemented
+	cpuid
+	cmpl    $0x80000001,%eax
+	jb      verify_cpu_no_longmode	# no extended cpuid
+
+	movl    $0x80000001,%eax	# Does the cpu have what it takes
+	cpuid
+	andl    $REQUIRED_MASK2,%edx
+	xorl    $REQUIRED_MASK2,%edx
+	jnz     verify_cpu_no_longmode
+
+verify_cpu_sse_test:
+	movl	$1,%eax
+	cpuid
+	andl	$SSE_MASK,%edx
+	cmpl	$SSE_MASK,%edx
+	je	verify_cpu_sse_ok
+	test	%di,%di
+	jz	verify_cpu_no_longmode	# only try to force SSE on AMD
+	movl	$0xc0010015,%ecx	# HWCR
+	rdmsr
+	btr	$15,%eax		# enable SSE
+	wrmsr
+	xor	%di,%di			# don't loop
+	jmp	verify_cpu_sse_test	# try again
+
+verify_cpu_no_longmode:
+	popfl				# Restore caller passed flags
+	movl $1,%eax
+	ret
+verify_cpu_sse_ok:
+	popfl				# Restore caller passed flags
+	xorl %eax, %eax
+	ret
_

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Arjan van de Ven]

On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
> Hi,
> 
> Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> patchset makes a bzImage relocatable and same kernel binary can be loaded
> and run from different physical addresses.


have these patches been extensively tested with various suspend
scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Eric W. Biederman]

Arjan van de Ven <arjan@infradead.org> writes:

> On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
>> Hi,
>> 
>> Here is another attempt on x86_64 relocatable bzImage patches(V4). This
>> patchset makes a bzImage relocatable and same kernel binary can be loaded
>> and run from different physical addresses.
>
>
> have these patches been extensively tested with various suspend
> scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)

It should be noted what broke was the non-portable constructs in the generic
suspend code.

In particular using __pa() outside of architecture code is not allowed.
Using virt_to_phys() on addresses not part of the kernel's linear mapping is
not generically supported.

text/data are not required to be part of the kernel's linear mapping.

This patchset now causes all code using these non-portable constructs to
fail on x86_64.  Which I think is a good thing so we can more easily
spot these kinds of problems.

Patches 15 and 16 appear to make the swpsuspend code rely on portable
constructs.   I will let Vivek reply to the amount of testing he has
done in this area.

Eric

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Nigel Cunningham]

Hi.

On Wed, 2007-03-07 at 07:07 -0800, Arjan van de Ven wrote:
> On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
> > Hi,
> > 
> > Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> > patchset makes a bzImage relocatable and same kernel binary can be loaded
> > and run from different physical addresses.
> 
> 
> have these patches been extensively tested with various suspend
> scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)

We did work on this for RHEL5, getting relocatable kernel support
working fine with S4. While doing it and since, I've been running
Suspend2 with the same patch.

Since that work, Vivek has done more modifications, but I can confirm
that the basic design is reliable with S4. Haven't tried S3, but can do.
Will report back shortly.

Regards,

Nigel

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Nigel Cunningham]

Hi.

On Thu, 2007-03-08 at 07:49 +1100, Nigel Cunningham wrote:
> Hi.
> 
> On Wed, 2007-03-07 at 07:07 -0800, Arjan van de Ven wrote:
> > On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
> > > Hi,
> > > 
> > > Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> > > patchset makes a bzImage relocatable and same kernel binary can be loaded
> > > and run from different physical addresses.
> > 
> > 
> > have these patches been extensively tested with various suspend
> > scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)
> 
> We did work on this for RHEL5, getting relocatable kernel support
> working fine with S4. While doing it and since, I've been running
> Suspend2 with the same patch.
> 
> Since that work, Vivek has done more modifications, but I can confirm
> that the basic design is reliable with S4. Haven't tried S3, but can do.
> Will report back shortly.

S3 works okay here with a relocatable x86_64 kernel (2.6.20).

Regards,

Nigel

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Vivek Goyal]

On Thu, Mar 08, 2007 at 10:15:02AM +1100, Nigel Cunningham wrote:
> Hi.
> 
> On Thu, 2007-03-08 at 07:49 +1100, Nigel Cunningham wrote:
> > Hi.
> > 
> > On Wed, 2007-03-07 at 07:07 -0800, Arjan van de Ven wrote:
> > > On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
> > > > Hi,
> > > > 
> > > > Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> > > > patchset makes a bzImage relocatable and same kernel binary can be loaded
> > > > and run from different physical addresses.
> > > 
> > > 
> > > have these patches been extensively tested with various suspend
> > > scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)
> > 
> > We did work on this for RHEL5, getting relocatable kernel support
> > working fine with S4. While doing it and since, I've been running
> > Suspend2 with the same patch.
> > 
> > Since that work, Vivek has done more modifications, but I can confirm
> > that the basic design is reliable with S4. Haven't tried S3, but can do.
> > Will report back shortly.
> 
> S3 works okay here with a relocatable x86_64 kernel (2.6.20).
> 

Hi Nigel,

Is it possible to test S3 with 2.6.21-rc2 kernels also. Right now I don't 
have access to any machine supporting S3. I tested it at the time of my last
posting and it had worked well. Appreciate your help.

Thanks
Vivek

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Nigel Cunningham]

Hi.

On Thu, 2007-03-08 at 10:10 +0530, Vivek Goyal wrote:
> On Thu, Mar 08, 2007 at 10:15:02AM +1100, Nigel Cunningham wrote:
> > Hi.
> > 
> > On Thu, 2007-03-08 at 07:49 +1100, Nigel Cunningham wrote:
> > > Hi.
> > > 
> > > On Wed, 2007-03-07 at 07:07 -0800, Arjan van de Ven wrote:
> > > > On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
> > > > > Hi,
> > > > > 
> > > > > Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> > > > > patchset makes a bzImage relocatable and same kernel binary can be loaded
> > > > > and run from different physical addresses.
> > > > 
> > > > 
> > > > have these patches been extensively tested with various suspend
> > > > scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)
> > > 
> > > We did work on this for RHEL5, getting relocatable kernel support
> > > working fine with S4. While doing it and since, I've been running
> > > Suspend2 with the same patch.
> > > 
> > > Since that work, Vivek has done more modifications, but I can confirm
> > > that the basic design is reliable with S4. Haven't tried S3, but can do.
> > > Will report back shortly.
> > 
> > S3 works okay here with a relocatable x86_64 kernel (2.6.20).
> > 
> 
> Hi Nigel,
> 
> Is it possible to test S3 with 2.6.21-rc2 kernels also. Right now I don't 
> have access to any machine supporting S3. I tested it at the time of my last
> posting and it had worked well. Appreciate your help.

Tested with rc3 (rc2 wouldn't compile), and it works fine.

If you're willing, please add

Signed-off-by: Nigel Cunningham <ncunning@redhat.com>

or

Acked-by: Nigel Cunningham <ncunning@redhat.com>

to the hibernation related parts as you see appropriate, since I helped
(albeit in a minor way compared to your work and Eric's work) with
preparing and testing them for RHEL5 and have confirmed they're still ok
in this version.

Regards,

Nigel

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Vivek Goyal]

On Thu, Mar 08, 2007 at 07:07:23PM +1100, Nigel Cunningham wrote:
> Hi.
> 
> On Thu, 2007-03-08 at 10:10 +0530, Vivek Goyal wrote:
> > On Thu, Mar 08, 2007 at 10:15:02AM +1100, Nigel Cunningham wrote:
> > > Hi.
> > > 
> > > On Thu, 2007-03-08 at 07:49 +1100, Nigel Cunningham wrote:
> > > > Hi.
> > > > 
> > > > On Wed, 2007-03-07 at 07:07 -0800, Arjan van de Ven wrote:
> > > > > On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
> > > > > > Hi,
> > > > > > 
> > > > > > Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> > > > > > patchset makes a bzImage relocatable and same kernel binary can be loaded
> > > > > > and run from different physical addresses.
> > > > > 
> > > > > 
> > > > > have these patches been extensively tested with various suspend
> > > > > scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)
> > > > 
> > > > We did work on this for RHEL5, getting relocatable kernel support
> > > > working fine with S4. While doing it and since, I've been running
> > > > Suspend2 with the same patch.
> > > > 
> > > > Since that work, Vivek has done more modifications, but I can confirm
> > > > that the basic design is reliable with S4. Haven't tried S3, but can do.
> > > > Will report back shortly.
> > > 
> > > S3 works okay here with a relocatable x86_64 kernel (2.6.20).
> > > 
> > 
> > Hi Nigel,
> > 
> > Is it possible to test S3 with 2.6.21-rc2 kernels also. Right now I don't 
> > have access to any machine supporting S3. I tested it at the time of my last
> > posting and it had worked well. Appreciate your help.
> 
> Tested with rc3 (rc2 wouldn't compile), and it works fine.
> 

Thanks a lot Nigel.

> If you're willing, please add
> 
> Signed-off-by: Nigel Cunningham <ncunning@redhat.com>
> 
> or
> 
> Acked-by: Nigel Cunningham <ncunning@redhat.com>
> 
> to the hibernation related parts as you see appropriate, since I helped
> (albeit in a minor way compared to your work and Eric's work) with
> preparing and testing them for RHEL5 and have confirmed they're still ok
> in this version.

Sure. You have helped a lot. I think either Andi or Andrew needs to
add "Acked-by:" string while adding the hibernation related patches
(Assuming they decide do pick up the patches.)

Thanks
Vivek

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Vivek Goyal]

On Thu, Mar 08, 2007 at 10:15:02AM +1100, Nigel Cunningham wrote:
> Hi.
> 
> On Thu, 2007-03-08 at 07:49 +1100, Nigel Cunningham wrote:
> > Hi.
> > 
> > On Wed, 2007-03-07 at 07:07 -0800, Arjan van de Ven wrote:
> > > On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
> > > > Hi,
> > > > 
> > > > Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> > > > patchset makes a bzImage relocatable and same kernel binary can be loaded
> > > > and run from different physical addresses.
> > > 
> > > 
> > > have these patches been extensively tested with various suspend
> > > scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)
> > 
> > We did work on this for RHEL5, getting relocatable kernel support
> > working fine with S4. While doing it and since, I've been running
> > Suspend2 with the same patch.
> > 
> > Since that work, Vivek has done more modifications, but I can confirm
> > that the basic design is reliable with S4. Haven't tried S3, but can do.
> > Will report back shortly.
> 
> S3 works okay here with a relocatable x86_64 kernel (2.6.20).
> 

Ok. Got hold of a system which supports Standby mode (S1) and it works fine
with 2.6.21-rc2 + relocatable patchset.

Thanks
Vivek

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Vivek Goyal]

On Wed, Mar 07, 2007 at 07:07:39AM -0800, Arjan van de Ven wrote:
> On Wed, 2007-03-07 at 12:27 +0530, Vivek Goyal wrote:
> > Hi,
> > 
> > Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> > patchset makes a bzImage relocatable and same kernel binary can be loaded
> > and run from different physical addresses.
> 
> 
> have these patches been extensively tested with various suspend
> scenarios? (S1,S3,S4 in acpi speak or s2ram and s2disk in Linux speak)

Hi Arjan,

I have tested these patches for suspend to RAM and suspend to disk and they
work fine. In the past we had few issues with suspend to disk and now
these issues have been resolved in this patchset. 

Thanks
Vivek

Re: [PATCH 0/20] x86_64 Relocatable bzImage support (V4)

[Andi Kleen]

On Wednesday 07 March 2007 07:57, Vivek Goyal wrote:
> Hi,
> 
> Here is another attempt on x86_64 relocatable bzImage patches(V4). This
> patchset makes a bzImage relocatable and same kernel binary can be loaded
> and run from different physical addresses.

I merged them all for now. Thanks.

-Andi