[GIT PULL 00/13] EFI changes for v4.6 part 2

[GIT PULL 00/13] EFI changes for v4.6 part 2

[Matt Fleming]

Folks, here are the remaining EFI changes for v4.6.

Two of the patches were sent in the previous v4.6 pull request on 1st
February. Those include running EFI runtime services with interrupts
enabled (just like Windows does) and aligning the EFI GUID formats in
include/linux/efi.h to match the way they're written in the UEFI spec.
They've both been reworked to address comments.

The rest of the changes are all over the tree, and range from simple
fixes and cleanups to support for EFI_PROPERTIES_TABLE on x86.

The following changes since commit 35575e0e8ba633fc8276509a21f89b599b4f9006:

  efi: Add Persistent Memory type name (2016-02-03 11:41:20 +0100)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi.git tags/efi-next

for you to fetch changes up to 83a901db98e790e5682b85b8ee85f9e545d84e27:

  x86/efi: Only map kernel text for EFI mixed mode (2016-02-15 11:37:02 +0000)

----------------------------------------------------------------
 * checkpatch.pl cleanup of the GUIDs in efi.h which has the added
   benefit of making them more closely resemble how they're presented
   in the UEFI specification - Peter Jones

 * Now that we've verified that Windows works this way, leave
   interrupts enabled when invoking EFI runtime services which
   also reduces interrupt latencies - Ard Biesheuvel

 * Reduce page table attribute inconsistencies between the EFI page
   tables and the standard kernel page tables by ensuring we also set
   _PAGE_GLOBAL in the EFI-specific paths - Sai Praneeth Prakhya

 * A bunch of small fixes to the generic EFI stub and some early boot
   platform compatibility checks for ARM and arm64 - Ard Biesheuvel

 * Add support for EFI_PROPERTIES_TABLE to x86, allowing us to apply
   more secure memory mapping permissions for firmware that ships with
   the feature enabled - Sai Praneeth Prakhya

 * Fix an EFI mixed mode bug where we intend to only map the kernel
   image's text but end up mapping the entire image - Sai Praneeth Prakhya

----------------------------------------------------------------
Ard Biesheuvel (8):
      efi/runtime-wrappers: Run UEFI Runtime Services with interrupts enabled
      efi/arm64: Drop __init annotation from handle_kernel_image()
      arm64: vmlinux.lds.S: Handle .init.rodata.xxx and .init.bss sections
      efi/efistub: Prevent __init annotations from being used
      efi/arm-init: Use read-only early mappings
      efi/arm: Check for LPAE support before booting a LPAE kernel
      efi/arm64: Check for h/w support before booting a >4 KB granule kernel
      efi/arm*: Perform hardware compatibility check

Peter Jones (1):
      efi: Reformat GUID tables to follow the format in UEFI spec

Sai Praneeth (4):
      x86/mm/pageattr: Use _PAGE_GLOBAL bit for EFI page table mappings
      x86/mm/pageattr: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()
      x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables
      x86/efi: Only map kernel text for EFI mixed mode

 arch/arm64/kernel/vmlinux.lds.S           |  1 +
 arch/x86/include/asm/efi.h                |  2 +-
 arch/x86/mm/pageattr.c                    | 17 ++++++++
 arch/x86/platform/efi/efi.c               |  9 +++-
 arch/x86/platform/efi/efi_32.c            |  2 +-
 arch/x86/platform/efi/efi_64.c            | 55 ++++++++++++++++++++----
 drivers/firmware/efi/arm-init.c           | 14 +++---
 drivers/firmware/efi/libstub/arm-stub.c   |  4 ++
 drivers/firmware/efi/libstub/arm32-stub.c | 17 ++++++++
 drivers/firmware/efi/libstub/arm64-stub.c | 34 ++++++++++++---
 drivers/firmware/efi/libstub/efistub.h    | 12 ++++++
 drivers/firmware/efi/runtime-wrappers.c   | 71 ++++++++++++-------------------
 include/linux/efi.h                       | 63 ++++++++++++++++++---------
 13 files changed, 210 insertions(+), 91 deletions(-)

[PATCH 03/13] x86/mm/pageattr: Use _PAGE_GLOBAL bit for EFI page table mappings

[Matt Fleming]

From: Sai Praneeth <sai.praneeth.prakhya@intel.com>

Since EFI page tables can be treated as kernel page tables they should
be global. All the other page mapping functions in pageattr.c set the
_PAGE_GLOBAL bit and we want to avoid inconsistencies when we map a page
in the EFI code paths, for example when that page is split in
__split_large_page(), etc. It also makes it easier to validate that the
EFI region mappings have the correct attributes because there are fewer
differences compared with regular kernel mappings.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 arch/x86/mm/pageattr.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 632d34d20237..bf312da41a6d 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -909,6 +909,20 @@ static void populate_pte(struct cpa_data *cpa,
 
 	pte = pte_offset_kernel(pmd, start);
 
+	/*
+	 * Set the GLOBAL flags only if the PRESENT flag is
+	 * set otherwise pte_present will return true even on
+	 * a non present pte. The canon_pgprot will clear
+	 * _PAGE_GLOBAL for the ancient hardware that doesn't
+	 * support it.
+	 */
+	if (pgprot_val(pgprot) & _PAGE_PRESENT)
+		pgprot_val(pgprot) |= _PAGE_GLOBAL;
+	else
+		pgprot_val(pgprot) &= ~_PAGE_GLOBAL;
+
+	pgprot = canon_pgprot(pgprot);
+
 	while (num_pages-- && start < end) {
 		set_pte(pte, pfn_pte(cpa->pfn, pgprot));
 
-- 
2.6.2

[PATCH 04/13] efi/arm64: Drop __init annotation from handle_kernel_image()

[Matt Fleming]

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

After moving arm64-stub.c to libstub/, all of its sections are emitted
as .init.xxx sections automatically, and the __init annotation of
handle_kernel_image() causes it to end up in .init.init.text, which is
not recognized as an __init section by the linker scripts. So drop the
annotation.

Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 drivers/firmware/efi/libstub/arm64-stub.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
index 78dfbd34b6bf..9e0342745e4f 100644
--- a/drivers/firmware/efi/libstub/arm64-stub.c
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -13,13 +13,13 @@
 #include <asm/efi.h>
 #include <asm/sections.h>
 
-efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table_arg,
-					unsigned long *image_addr,
-					unsigned long *image_size,
-					unsigned long *reserve_addr,
-					unsigned long *reserve_size,
-					unsigned long dram_base,
-					efi_loaded_image_t *image)
+efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg,
+				 unsigned long *image_addr,
+				 unsigned long *image_size,
+				 unsigned long *reserve_addr,
+				 unsigned long *reserve_size,
+				 unsigned long dram_base,
+				 efi_loaded_image_t *image)
 {
 	efi_status_t status;
 	unsigned long kernel_size, kernel_memsize = 0;
-- 
2.6.2

[PATCH 01/13] efi: Reformat GUID tables to follow the format in UEFI spec

[Matt Fleming]

From: Peter Jones <pjones-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

This makes it much easier to hunt for typos in the GUID definitions.

It also makes checkpatch complain less about efi.h GUID additions, so
that if you add another one with the same style, checkpatch won't
complain about it.

Signed-off-by: Peter Jones <pjones-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
Cc: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Signed-off-by: Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>
---
 include/linux/efi.h | 63 +++++++++++++++++++++++++++++++++++------------------
 1 file changed, 42 insertions(+), 21 deletions(-)

diff --git a/include/linux/efi.h b/include/linux/efi.h
index 3c6cbbdae4aa..99b88c5a6770 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -536,67 +536,88 @@ void efi_native_runtime_setup(void);
  *  EFI Configuration Table and GUID definitions
  */
 #define NULL_GUID \
-    EFI_GUID(  0x00000000, 0x0000, 0x0000, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 )
+	EFI_GUID(0x00000000, 0x0000, 0x0000, \
+		 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00)
 
 #define MPS_TABLE_GUID    \
-    EFI_GUID(  0xeb9d2d2f, 0x2d88, 0x11d3, 0x9a, 0x16, 0x0, 0x90, 0x27, 0x3f, 0xc1, 0x4d )
+	EFI_GUID(0xeb9d2d2f, 0x2d88, 0x11d3, \
+		 0x9a, 0x16, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
 
 #define ACPI_TABLE_GUID    \
-    EFI_GUID(  0xeb9d2d30, 0x2d88, 0x11d3, 0x9a, 0x16, 0x0, 0x90, 0x27, 0x3f, 0xc1, 0x4d )
+	EFI_GUID(0xeb9d2d30, 0x2d88, 0x11d3, \
+		 0x9a, 0x16, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
 
 #define ACPI_20_TABLE_GUID    \
-    EFI_GUID(  0x8868e871, 0xe4f1, 0x11d3, 0xbc, 0x22, 0x0, 0x80, 0xc7, 0x3c, 0x88, 0x81 )
+	EFI_GUID(0x8868e871, 0xe4f1, 0x11d3, \
+		 0xbc, 0x22, 0x00, 0x80, 0xc7, 0x3c, 0x88, 0x81)
 
 #define SMBIOS_TABLE_GUID    \
-    EFI_GUID(  0xeb9d2d31, 0x2d88, 0x11d3, 0x9a, 0x16, 0x0, 0x90, 0x27, 0x3f, 0xc1, 0x4d )
+	EFI_GUID(0xeb9d2d31, 0x2d88, 0x11d3, \
+		 0x9a, 0x16, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
 
 #define SMBIOS3_TABLE_GUID    \
-    EFI_GUID(  0xf2fd1544, 0x9794, 0x4a2c, 0x99, 0x2e, 0xe5, 0xbb, 0xcf, 0x20, 0xe3, 0x94 )
+	EFI_GUID(0xf2fd1544, 0x9794, 0x4a2c, \
+		 0x99, 0x2e, 0xe5, 0xbb, 0xcf, 0x20, 0xe3, 0x94)
 
 #define SAL_SYSTEM_TABLE_GUID    \
-    EFI_GUID(  0xeb9d2d32, 0x2d88, 0x11d3, 0x9a, 0x16, 0x0, 0x90, 0x27, 0x3f, 0xc1, 0x4d )
+	EFI_GUID(0xeb9d2d32, 0x2d88, 0x11d3, \
+		 0x9a, 0x16, 0x00, 0x90, 0x27, 0x3f, 0xc1, 0x4d)
 
 #define HCDP_TABLE_GUID	\
-    EFI_GUID(  0xf951938d, 0x620b, 0x42ef, 0x82, 0x79, 0xa8, 0x4b, 0x79, 0x61, 0x78, 0x98 )
+	EFI_GUID(0xf951938d, 0x620b, 0x42ef, \
+		 0x82, 0x79, 0xa8, 0x4b, 0x79, 0x61, 0x78, 0x98)
 
 #define UGA_IO_PROTOCOL_GUID \
-    EFI_GUID(  0x61a4d49e, 0x6f68, 0x4f1b, 0xb9, 0x22, 0xa8, 0x6e, 0xed, 0xb, 0x7, 0xa2 )
+	EFI_GUID(0x61a4d49e, 0x6f68, 0x4f1b, \
+		 0xb9, 0x22, 0xa8, 0x6e, 0xed, 0x0b, 0x07, 0xa2)
 
 #define EFI_GLOBAL_VARIABLE_GUID \
-    EFI_GUID(  0x8be4df61, 0x93ca, 0x11d2, 0xaa, 0x0d, 0x00, 0xe0, 0x98, 0x03, 0x2b, 0x8c )
+	EFI_GUID(0x8be4df61, 0x93ca, 0x11d2, \
+		 0xaa, 0x0d, 0x00, 0xe0, 0x98, 0x03, 0x2b, 0x8c)
 
 #define UV_SYSTEM_TABLE_GUID \
-    EFI_GUID(  0x3b13a7d4, 0x633e, 0x11dd, 0x93, 0xec, 0xda, 0x25, 0x56, 0xd8, 0x95, 0x93 )
+	EFI_GUID(0x3b13a7d4, 0x633e, 0x11dd, \
+		 0x93, 0xec, 0xda, 0x25, 0x56, 0xd8, 0x95, 0x93)
 
 #define LINUX_EFI_CRASH_GUID \
-    EFI_GUID(  0xcfc8fc79, 0xbe2e, 0x4ddc, 0x97, 0xf0, 0x9f, 0x98, 0xbf, 0xe2, 0x98, 0xa0 )
+	EFI_GUID(0xcfc8fc79, 0xbe2e, 0x4ddc, \
+		 0x97, 0xf0, 0x9f, 0x98, 0xbf, 0xe2, 0x98, 0xa0)
 
 #define LOADED_IMAGE_PROTOCOL_GUID \
-    EFI_GUID(  0x5b1b31a1, 0x9562, 0x11d2, 0x8e, 0x3f, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b )
+	EFI_GUID(0x5b1b31a1, 0x9562, 0x11d2, \
+		 0x8e, 0x3f, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
 
 #define EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID \
-    EFI_GUID(  0x9042a9de, 0x23dc, 0x4a38, 0x96, 0xfb, 0x7a, 0xde, 0xd0, 0x80, 0x51, 0x6a )
+	EFI_GUID(0x9042a9de, 0x23dc, 0x4a38, \
+		 0x96, 0xfb, 0x7a, 0xde, 0xd0, 0x80, 0x51, 0x6a)
 
 #define EFI_UGA_PROTOCOL_GUID \
-    EFI_GUID(  0x982c298b, 0xf4fa, 0x41cb, 0xb8, 0x38, 0x77, 0xaa, 0x68, 0x8f, 0xb8, 0x39 )
+	EFI_GUID(0x982c298b, 0xf4fa, 0x41cb, \
+		 0xb8, 0x38, 0x77, 0xaa, 0x68, 0x8f, 0xb8, 0x39)
 
 #define EFI_PCI_IO_PROTOCOL_GUID \
-    EFI_GUID(  0x4cf5b200, 0x68b8, 0x4ca5, 0x9e, 0xec, 0xb2, 0x3e, 0x3f, 0x50, 0x2, 0x9a )
+	EFI_GUID(0x4cf5b200, 0x68b8, 0x4ca5, \
+		 0x9e, 0xec, 0xb2, 0x3e, 0x3f, 0x50, 0x02, 0x9a)
 
 #define EFI_FILE_INFO_ID \
-    EFI_GUID(  0x9576e92, 0x6d3f, 0x11d2, 0x8e, 0x39, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b )
+	EFI_GUID(0x9576e92, 0x6d3f, 0x11d2, \
+		 0x8e, 0x39, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
 
 #define EFI_SYSTEM_RESOURCE_TABLE_GUID \
-    EFI_GUID(  0xb122a263, 0x3661, 0x4f68, 0x99, 0x29, 0x78, 0xf8, 0xb0, 0xd6, 0x21, 0x80 )
+	EFI_GUID(0xb122a263, 0x3661, 0x4f68, \
+		 0x99, 0x29, 0x78, 0xf8, 0xb0, 0xd6, 0x21, 0x80)
 
 #define EFI_FILE_SYSTEM_GUID \
-    EFI_GUID(  0x964e5b22, 0x6459, 0x11d2, 0x8e, 0x39, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b )
+	EFI_GUID(0x964e5b22, 0x6459, 0x11d2, \
+		 0x8e, 0x39, 0x00, 0xa0, 0xc9, 0x69, 0x72, 0x3b)
 
 #define DEVICE_TREE_GUID \
-    EFI_GUID(  0xb1b621d5, 0xf19c, 0x41a5, 0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0 )
+	EFI_GUID(0xb1b621d5, 0xf19c, 0x41a5, \
+		 0x83, 0x0b, 0xd9, 0x15, 0x2c, 0x69, 0xaa, 0xe0)
 
 #define EFI_PROPERTIES_TABLE_GUID \
-    EFI_GUID(  0x880aaca3, 0x4adc, 0x4a04, 0x90, 0x79, 0xb7, 0x47, 0x34, 0x08, 0x25, 0xe5 )
+	EFI_GUID(0x880aaca3, 0x4adc, 0x4a04, \
+		 0x90, 0x79, 0xb7, 0x47, 0x34, 0x08, 0x25, 0xe5)
 
 typedef struct {
 	efi_guid_t guid;
-- 
2.6.2

[PATCH 02/13] efi/runtime-wrappers: Run UEFI Runtime Services with interrupts enabled

[Matt Fleming]

From: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>

The UEFI spec allows Runtime Services to be invoked with interrupts
enabled. The only reason we were disabling interrupts was to prevent
recursive calls into the services on the same CPU, which will lead to
deadlock. However, the only context where such invocations may occur
legally is from efi-pstore via efivars, and that code has been updated
to call a non-blocking alternative when invoked from a non-interruptible
context.

So instead, update the ordinary, blocking UEFI Runtime Services wrappers
to execute with interrupts enabled. This aims to prevent excessive interrupt
latencies on uniprocessor platforms with slow variable stores.

Note that other OSes such as Windows call UEFI Runtime Services with
interrupts enabled as well.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>
Cc: Linus Torvalds <torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Cc: Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>
Signed-off-by: Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>
---
 drivers/firmware/efi/runtime-wrappers.c | 71 +++++++++++++--------------------
 1 file changed, 28 insertions(+), 43 deletions(-)

diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c
index 7b8b2f2702ca..de6953039af6 100644
--- a/drivers/firmware/efi/runtime-wrappers.c
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -63,23 +63,21 @@ static DEFINE_SPINLOCK(efi_runtime_lock);
 
 static efi_status_t virt_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(get_time, tm, tc);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
 static efi_status_t virt_efi_set_time(efi_time_t *tm)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(set_time, tm);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -87,23 +85,21 @@ static efi_status_t virt_efi_get_wakeup_time(efi_bool_t *enabled,
 					     efi_bool_t *pending,
 					     efi_time_t *tm)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(get_wakeup_time, enabled, pending, tm);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
 static efi_status_t virt_efi_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(set_wakeup_time, enabled, tm);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -113,13 +109,12 @@ static efi_status_t virt_efi_get_variable(efi_char16_t *name,
 					  unsigned long *data_size,
 					  void *data)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(get_variable, name, vendor, attr, data_size,
 			       data);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -127,12 +122,11 @@ static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 					       efi_char16_t *name,
 					       efi_guid_t *vendor)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(get_next_variable, name_size, name, vendor);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -142,13 +136,12 @@ static efi_status_t virt_efi_set_variable(efi_char16_t *name,
 					  unsigned long data_size,
 					  void *data)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(set_variable, name, vendor, attr, data_size,
 			       data);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -157,15 +150,14 @@ virt_efi_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor,
 				  u32 attr, unsigned long data_size,
 				  void *data)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
+	if (!spin_trylock(&efi_runtime_lock))
 		return EFI_NOT_READY;
 
 	status = efi_call_virt(set_variable, name, vendor, attr, data_size,
 			       data);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -175,16 +167,15 @@ static efi_status_t virt_efi_query_variable_info(u32 attr,
 						 u64 *remaining_space,
 						 u64 *max_variable_size)
 {
-	unsigned long flags;
 	efi_status_t status;
 
 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 		return EFI_UNSUPPORTED;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(query_variable_info, attr, storage_space,
 			       remaining_space, max_variable_size);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -194,29 +185,27 @@ virt_efi_query_variable_info_nonblocking(u32 attr,
 					 u64 *remaining_space,
 					 u64 *max_variable_size)
 {
-	unsigned long flags;
 	efi_status_t status;
 
 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 		return EFI_UNSUPPORTED;
 
-	if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
+	if (!spin_trylock(&efi_runtime_lock))
 		return EFI_NOT_READY;
 
 	status = efi_call_virt(query_variable_info, attr, storage_space,
 			       remaining_space, max_variable_size);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
 static efi_status_t virt_efi_get_next_high_mono_count(u32 *count)
 {
-	unsigned long flags;
 	efi_status_t status;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(get_next_high_mono_count, count);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -225,26 +214,23 @@ static void virt_efi_reset_system(int reset_type,
 				  unsigned long data_size,
 				  efi_char16_t *data)
 {
-	unsigned long flags;
-
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	__efi_call_virt(reset_system, reset_type, status, data_size, data);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 }
 
 static efi_status_t virt_efi_update_capsule(efi_capsule_header_t **capsules,
 					    unsigned long count,
 					    unsigned long sg_list)
 {
-	unsigned long flags;
 	efi_status_t status;
 
 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 		return EFI_UNSUPPORTED;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(update_capsule, capsules, count, sg_list);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
@@ -253,16 +239,15 @@ static efi_status_t virt_efi_query_capsule_caps(efi_capsule_header_t **capsules,
 						u64 *max_size,
 						int *reset_type)
 {
-	unsigned long flags;
 	efi_status_t status;
 
 	if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 		return EFI_UNSUPPORTED;
 
-	spin_lock_irqsave(&efi_runtime_lock, flags);
+	spin_lock(&efi_runtime_lock);
 	status = efi_call_virt(query_capsule_caps, capsules, count, max_size,
 			       reset_type);
-	spin_unlock_irqrestore(&efi_runtime_lock, flags);
+	spin_unlock(&efi_runtime_lock);
 	return status;
 }
 
-- 
2.6.2

[PATCH 05/13] arm64: vmlinux.lds.S: Handle .init.rodata.xxx and .init.bss sections

[Matt Fleming]

From: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>

The EFI stub is typically built into the decompressor (x86, ARM) so none
of its symbols are annotated as __init. However, on arm64, the stub is
linked into the kernel proper, and the code is __init annotated at the
section level by prepending all names of SHF_ALLOC sections with '.init'.

This results in section names like .init.rodata.str1.8 (for string literals)
and .init.bss (which is tiny), both of which can be moved into the .init.data
output section.

Acked-by: Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>
Acked-by: Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>
Tested-by: Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Signed-off-by: Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>
---
 arch/arm64/kernel/vmlinux.lds.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
index e3928f578891..cbf4db440e9c 100644
--- a/arch/arm64/kernel/vmlinux.lds.S
+++ b/arch/arm64/kernel/vmlinux.lds.S
@@ -134,6 +134,7 @@ SECTIONS
 		CON_INITCALL
 		SECURITY_INITCALL
 		INIT_RAM_FS
+		*(.init.rodata.* .init.bss)	/* from the EFI stub */
 	}
 	.exit.data : {
 		ARM_EXIT_KEEP(EXIT_DATA)
-- 
2.6.2

[PATCH 13/13] x86/efi: Only map kernel text for EFI mixed mode

[Matt Fleming]

From: Sai Praneeth <sai.praneeth.prakhya-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>

The correct symbol to use when figuring out the size of the kernel
text is '_etext', not '_end' which is the symbol for the entire kernel
image includes data and debug sections.

Cc: Borislav Petkov <bp-Gina5bIWoIWzQB+pC5nmwQ@public.gmane.org>
Cc: Ricardo Neri <ricardo.neri-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Cc: Ravi Shankar <ravi.v.shankar-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>
---
 arch/x86/platform/efi/efi_64.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 40d2f447a9dd..49e4dd4a1f58 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -275,7 +275,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 	efi_scratch.phys_stack = virt_to_phys(page_address(page));
 	efi_scratch.phys_stack += PAGE_SIZE; /* stack grows down */
 
-	npages = (_end - _text) >> PAGE_SHIFT;
+	npages = (_etext - _text) >> PAGE_SHIFT;
 	text = __pa(_text);
 	pfn = text >> PAGE_SHIFT;
 
-- 
2.6.2

[PATCH 06/13] efi/efistub: Prevent __init annotations from being used

[Matt Fleming]

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

__init annotations should not be used in the EFI stub, since the code is
either included in the decompressor (x86, ARM) where they have no effect,
or the whole stub is __init annotated at the section level (arm64), by
renaming the sections, in which case the __init annotations will be
redundant, and will result in section names like .init.init.text, and our
linker script does not expect that. So un-#define __init so that its
inadvertent use will force a build error.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 drivers/firmware/efi/libstub/efistub.h | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index 6b6548fda089..86ff7bfa6ace 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -5,6 +5,16 @@
 /* error code which can't be mistaken for valid address */
 #define EFI_ERROR	(~0UL)
 
+/*
+ * __init annotations should not be used in the EFI stub, since the code is
+ * either included in the decompressor (x86, ARM) where they have no effect,
+ * or the whole stub is __init annotated at the section level (arm64), by
+ * renaming the sections, in which case the __init annotation will be
+ * redundant, and will result in section names like .init.init.text, and our
+ * linker script does not expect that.
+ */
+#undef __init
+
 void efi_char16_printk(efi_system_table_t *, efi_char16_t *);
 
 efi_status_t efi_open_volume(efi_system_table_t *sys_table_arg, void *__image,
-- 
2.6.2

[PATCH 07/13] efi/arm-init: Use read-only early mappings

[Matt Fleming]

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

The early mappings of the EFI system table contents and the UEFI memory
map are read-only from the OS point of view. So map them read-only to
protect them from inadvertent modification.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 drivers/firmware/efi/arm-init.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/firmware/efi/arm-init.c b/drivers/firmware/efi/arm-init.c
index 9e15d571b53c..aa1f743152a2 100644
--- a/drivers/firmware/efi/arm-init.c
+++ b/drivers/firmware/efi/arm-init.c
@@ -61,8 +61,8 @@ static int __init uefi_init(void)
 	char vendor[100] = "unknown";
 	int i, retval;
 
-	efi.systab = early_memremap(efi_system_table,
-				    sizeof(efi_system_table_t));
+	efi.systab = early_memremap_ro(efi_system_table,
+				       sizeof(efi_system_table_t));
 	if (efi.systab == NULL) {
 		pr_warn("Unable to map EFI system table.\n");
 		return -ENOMEM;
@@ -86,8 +86,8 @@ static int __init uefi_init(void)
 			efi.systab->hdr.revision & 0xffff);
 
 	/* Show what we know for posterity */
-	c16 = early_memremap(efi_to_phys(efi.systab->fw_vendor),
-			     sizeof(vendor) * sizeof(efi_char16_t));
+	c16 = early_memremap_ro(efi_to_phys(efi.systab->fw_vendor),
+				sizeof(vendor) * sizeof(efi_char16_t));
 	if (c16) {
 		for (i = 0; i < (int) sizeof(vendor) - 1 && *c16; ++i)
 			vendor[i] = c16[i];
@@ -100,8 +100,8 @@ static int __init uefi_init(void)
 		efi.systab->hdr.revision & 0xffff, vendor);
 
 	table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables;
-	config_tables = early_memremap(efi_to_phys(efi.systab->tables),
-				       table_size);
+	config_tables = early_memremap_ro(efi_to_phys(efi.systab->tables),
+					  table_size);
 	if (config_tables == NULL) {
 		pr_warn("Unable to map EFI config table array.\n");
 		retval = -ENOMEM;
@@ -185,7 +185,7 @@ void __init efi_init(void)
 	efi_system_table = params.system_table;
 
 	memmap.phys_map = params.mmap;
-	memmap.map = early_memremap(params.mmap, params.mmap_size);
+	memmap.map = early_memremap_ro(params.mmap, params.mmap_size);
 	if (memmap.map == NULL) {
 		/*
 		* If we are booting via UEFI, the UEFI memory map is the only
-- 
2.6.2

[PATCH 08/13] efi/arm: Check for LPAE support before booting a LPAE kernel

[Matt Fleming]

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

A kernel built with support for LPAE cannot boot to a state where it
can inform the user about it if it fails due to missing LPAE support
in the hardware.

If we happen to be booting via UEFI, we can fail gracefully so check
for LPAE support in the hardware on CONFIG_ARM_LPAE builds before
entering the kernel proper.

Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 drivers/firmware/efi/libstub/arm32-stub.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/firmware/efi/libstub/arm32-stub.c b/drivers/firmware/efi/libstub/arm32-stub.c
index 495ebd657e38..6f42be4d0084 100644
--- a/drivers/firmware/efi/libstub/arm32-stub.c
+++ b/drivers/firmware/efi/libstub/arm32-stub.c
@@ -9,6 +9,23 @@
 #include <linux/efi.h>
 #include <asm/efi.h>
 
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
+{
+	int block;
+
+	/* non-LPAE kernels can run anywhere */
+	if (!IS_ENABLED(CONFIG_ARM_LPAE))
+		return EFI_SUCCESS;
+
+	/* LPAE kernels need compatible hardware */
+	block = cpuid_feature_extract(CPUID_EXT_MMFR0, 0);
+	if (block < 5) {
+		pr_efi_err(sys_table_arg, "This LPAE kernel is not supported by your CPU\n");
+		return EFI_UNSUPPORTED;
+	}
+	return EFI_SUCCESS;
+}
+
 efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
 				 unsigned long *image_addr,
 				 unsigned long *image_size,
-- 
2.6.2

[PATCH 09/13] efi/arm64: Check for h/w support before booting a >4 KB granule kernel

[Matt Fleming]

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

A kernel built with support for a page size that is not supported by the
hardware it runs on cannot boot to a state where it can inform the user
about it.

If we happen to be booting via UEFI, we can fail gracefully so check
if the currently configured page size is supported by the hardware before
entering the kernel proper. Note that UEFI mandates support for 4 KB pages,
so in that case, no check is needed.

Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 drivers/firmware/efi/libstub/arm64-stub.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
index 9e0342745e4f..aef04ad60e0d 100644
--- a/drivers/firmware/efi/libstub/arm64-stub.c
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -12,6 +12,26 @@
 #include <linux/efi.h>
 #include <asm/efi.h>
 #include <asm/sections.h>
+#include <asm/sysreg.h>
+
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
+{
+	u64 tg;
+
+	/* UEFI mandates support for 4 KB granule, no need to check */
+	if (IS_ENABLED(CONFIG_ARM64_4K_PAGES))
+		return EFI_SUCCESS;
+
+	tg = (read_cpuid(ID_AA64MMFR0_EL1) >> ID_AA64MMFR0_TGRAN_SHIFT) & 0xf;
+	if (tg != ID_AA64MMFR0_TGRAN_SUPPORTED) {
+		if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
+			pr_efi_err(sys_table_arg, "This 64 KB granule kernel is not supported by your CPU\n");
+		else
+			pr_efi_err(sys_table_arg, "This 16 KB granule kernel is not supported by your CPU\n");
+		return EFI_UNSUPPORTED;
+	}
+	return EFI_SUCCESS;
+}
 
 efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg,
 				 unsigned long *image_addr,
-- 
2.6.2

Re: [PATCH 09/13] efi/arm64: Check for h/w support before booting a >4 KB granule kernel

[Ard Biesheuvel]

On 17 February 2016 at 13:36, Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org> wrote:
> From: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
>
> A kernel built with support for a page size that is not supported by the
> hardware it runs on cannot boot to a state where it can inform the user
> about it.
>
> If we happen to be booting via UEFI, we can fail gracefully so check
> if the currently configured page size is supported by the hardware before
> entering the kernel proper. Note that UEFI mandates support for 4 KB pages,
> so in that case, no check is needed.
>
> Reviewed-by: Jeremy Linton <jeremy.linton-5wv7dgnIgG8@public.gmane.org>
> Tested-by: Suzuki K Poulose <suzuki.poulose-5wv7dgnIgG8@public.gmane.org>
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
> Acked-by: Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>
> Signed-off-by: Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org>

Hi Matt,

This patch turned up in -next with 'granule' replaced with 'granular',
both in the commit log and in the patch itself. The term 'granule' is
part of the idiom used by the ARM Architecture Reference Manual, and
so changing it silently to 'granular' is not entirely appropriate here
(although harmless in practice, obviously). In general, I would
appreciate it if in the future, such changes were not made silently
somewhere in the merge pipeline.

Thanks,
Ard.


> ---
>  drivers/firmware/efi/libstub/arm64-stub.c | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
>
> diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
> index 9e0342745e4f..aef04ad60e0d 100644
> --- a/drivers/firmware/efi/libstub/arm64-stub.c
> +++ b/drivers/firmware/efi/libstub/arm64-stub.c
> @@ -12,6 +12,26 @@
>  #include <linux/efi.h>
>  #include <asm/efi.h>
>  #include <asm/sections.h>
> +#include <asm/sysreg.h>
> +
> +efi_status_t check_platform_features(efi_system_table_t *sys_table_arg)
> +{
> +       u64 tg;
> +
> +       /* UEFI mandates support for 4 KB granule, no need to check */
> +       if (IS_ENABLED(CONFIG_ARM64_4K_PAGES))
> +               return EFI_SUCCESS;
> +
> +       tg = (read_cpuid(ID_AA64MMFR0_EL1) >> ID_AA64MMFR0_TGRAN_SHIFT) & 0xf;
> +       if (tg != ID_AA64MMFR0_TGRAN_SUPPORTED) {
> +               if (IS_ENABLED(CONFIG_ARM64_64K_PAGES))
> +                       pr_efi_err(sys_table_arg, "This 64 KB granule kernel is not supported by your CPU\n");
> +               else
> +                       pr_efi_err(sys_table_arg, "This 16 KB granule kernel is not supported by your CPU\n");
> +               return EFI_UNSUPPORTED;
> +       }
> +       return EFI_SUCCESS;
> +}
>
>  efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg,
>                                  unsigned long *image_addr,
> --
> 2.6.2
>

Re: [PATCH 09/13] efi/arm64: Check for h/w support before booting a >4 KB granule kernel

[Matt Fleming]

On Sun, 06 Mar, at 04:35:32AM, Ard Biesheuvel wrote:
> 
> Hi Matt,
> 
> This patch turned up in -next with 'granule' replaced with 'granular',
> both in the commit log and in the patch itself. The term 'granule' is
> part of the idiom used by the ARM Architecture Reference Manual, and
> so changing it silently to 'granular' is not entirely appropriate here
> (although harmless in practice, obviously). In general, I would
> appreciate it if in the future, such changes were not made silently
> somewhere in the merge pipeline.

Sorry about this Ard. I'll make sure this doesn't happen again in
future.

Ingo, is there any chance we can fixup this patch in-place and revert
back to the original wording before it gets to Linus' during the merge
window?

Re: [PATCH 09/13] efi/arm64: Check for h/w support before booting a >4 KB granule kernel

[Ard Biesheuvel]

On 7 March 2016 at 18:02, Matt Fleming <matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org> wrote:
> On Sun, 06 Mar, at 04:35:32AM, Ard Biesheuvel wrote:
>>
>> Hi Matt,
>>
>> This patch turned up in -next with 'granule' replaced with 'granular',
>> both in the commit log and in the patch itself. The term 'granule' is
>> part of the idiom used by the ARM Architecture Reference Manual, and
>> so changing it silently to 'granular' is not entirely appropriate here
>> (although harmless in practice, obviously). In general, I would
>> appreciate it if in the future, such changes were not made silently
>> somewhere in the merge pipeline.
>
> Sorry about this Ard. I'll make sure this doesn't happen again in
> future.
>

Thanks

> Ingo, is there any chance we can fixup this patch in-place and revert
> back to the original wording before it gets to Linus' during the merge
> window?

To be honest, I don't care deeply about the commit log, as long as the
code changes are reverted.

Thanks,
Ard.

[PATCH 10/13] efi/arm*: Perform hardware compatibility check

[Matt Fleming]

From: Ard Biesheuvel <ard.biesheuvel@linaro.org>

Before proceeding with relocating the kernel and parsing the command line,
insert a call to check_platform_features() to allow an arch specific check
to be performed whether the current kernel can execute on the current
hardware.

Reviewed-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 drivers/firmware/efi/libstub/arm-stub.c | 4 ++++
 drivers/firmware/efi/libstub/efistub.h  | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index 3397902e4040..6086a874fa3c 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
@@ -190,6 +190,10 @@ unsigned long efi_entry(void *handle, efi_system_table_t *sys_table,
 
 	pr_efi(sys_table, "Booting Linux Kernel...\n");
 
+	status = check_platform_features(sys_table);
+	if (status != EFI_SUCCESS)
+		goto fail;
+
 	/*
 	 * Get a handle to the loaded image protocol.  This is used to get
 	 * information about the running image, such as size and the command
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index 86ff7bfa6ace..981c6035ce09 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -53,4 +53,6 @@ void efi_get_virtmap(efi_memory_desc_t *memory_map, unsigned long map_size,
 		     unsigned long desc_size, efi_memory_desc_t *runtime_map,
 		     int *count);
 
+efi_status_t check_platform_features(efi_system_table_t *sys_table_arg);
+
 #endif
-- 
2.6.2

[PATCH 11/13] x86/mm/pageattr: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()

[Matt Fleming]

From: Sai Praneeth <sai.praneeth.prakhya@intel.com>

As part of the preparation for the EFI_MEMORY_RO flag added in the UEFI
2.5 specification, we need the ability to map pages in kernel page
tables without _PAGE_RW being set.

Modify kernel_map_pages_in_pgd() to require its callers to pass _PAGE_RW
if the pages need to be mapped read/write. Otherwise, we'll map the
pages as read-only.

Cc: Borislav Petkov <bp@alien8.de>
Cc: "Lee, Chun-Yi" <jlee@suse.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 arch/x86/mm/pageattr.c         | 3 +++
 arch/x86/platform/efi/efi_64.c | 8 ++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index bf312da41a6d..14c38ae80409 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -1971,6 +1971,9 @@ int kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, unsigned long address,
 	if (!(page_flags & _PAGE_NX))
 		cpa.mask_clr = __pgprot(_PAGE_NX);
 
+	if (!(page_flags & _PAGE_RW))
+		cpa.mask_clr = __pgprot(_PAGE_RW);
+
 	cpa.mask_set = __pgprot(_PAGE_PRESENT | page_flags);
 
 	retval = __change_page_attr_set_clr(&cpa, 0);
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index b492521503fe..b0965b27e47f 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -233,7 +233,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 	 * phys_efi_set_virtual_address_map().
 	 */
 	pfn = pa_memmap >> PAGE_SHIFT;
-	if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, _PAGE_NX)) {
+	if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, _PAGE_NX | _PAGE_RW)) {
 		pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap);
 		return 1;
 	}
@@ -262,7 +262,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 		pfn = md->phys_addr >> PAGE_SHIFT;
 		npages = md->num_pages;
 
-		if (kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, npages, 0)) {
+		if (kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, npages, _PAGE_RW)) {
 			pr_err("Failed to map 1:1 memory\n");
 			return 1;
 		}
@@ -279,7 +279,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 	text = __pa(_text);
 	pfn = text >> PAGE_SHIFT;
 
-	if (kernel_map_pages_in_pgd(pgd, pfn, text, npages, 0)) {
+	if (kernel_map_pages_in_pgd(pgd, pfn, text, npages, _PAGE_RW)) {
 		pr_err("Failed to map kernel text 1:1\n");
 		return 1;
 	}
@@ -294,7 +294,7 @@ void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 
 static void __init __map_region(efi_memory_desc_t *md, u64 va)
 {
-	unsigned long flags = 0;
+	unsigned long flags = _PAGE_RW;
 	unsigned long pfn;
 	pgd_t *pgd = efi_pgd;
 
-- 
2.6.2

[PATCH 12/13] x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables

[Matt Fleming]

From: Sai Praneeth <sai.praneeth.prakhya@intel.com>

Now that we have EFI memory region bits that indicate which regions do
not need execute permission or read/write permission in the page tables,
let's use them.

We also check for EFI_NX_PE_DATA and only enforce the restrictive
mappings if it's present (to allow us to ignore buggy firmware that sets
bits it didn't mean to and to preserve backwards compatibility).

Instead of assuming that firmware would set appropriate attributes in
memory descriptor like EFI_MEMORY_RO for code and EFI_MEMORY_XP for
data, we can expect some firmware out there which might only set *type*
in memory descriptor to be EFI_RUNTIME_SERVICES_CODE or
EFI_RUNTIME_SERVICES_DATA leaving away attribute. This will lead to
improper mappings of EFI runtime regions. In order to avoid it, we check
attribute and type of memory descriptor to update mappings and moreover
Windows works this way.

Cc: Borislav Petkov <bp@alien8.de>
Cc: "Lee, Chun-Yi" <jlee@suse.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
---
 arch/x86/include/asm/efi.h     |  2 +-
 arch/x86/platform/efi/efi.c    |  9 +++++++--
 arch/x86/platform/efi/efi_32.c |  2 +-
 arch/x86/platform/efi/efi_64.c | 45 ++++++++++++++++++++++++++++++++++++++----
 4 files changed, 50 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 8fd9e637629a..7bb206f73915 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -141,7 +141,7 @@ extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pa
 extern void __init efi_cleanup_page_tables(unsigned long pa_memmap, unsigned num_pages);
 extern void __init old_map_region(efi_memory_desc_t *md);
 extern void __init runtime_code_page_mkexec(void);
-extern void __init efi_runtime_mkexec(void);
+extern void __init efi_runtime_update_mappings(void);
 extern void __init efi_dump_pagetable(void);
 extern void __init efi_apply_memmap_quirks(void);
 extern int __init efi_reuse_config(u64 tables, int nr_tables);
diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index e80826e6f3a9..994a7df84a7b 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -934,7 +934,6 @@ static void __init __efi_enter_virtual_mode(void)
 	}
 
 	efi_sync_low_kernel_mappings();
-	efi_dump_pagetable();
 
 	if (efi_is_native()) {
 		status = phys_efi_set_virtual_address_map(
@@ -972,7 +971,13 @@ static void __init __efi_enter_virtual_mode(void)
 
 	efi.set_virtual_address_map = NULL;
 
-	efi_runtime_mkexec();
+	/*
+	 * Apply more restrictive page table mapping attributes now that
+	 * SVAM() has been called and the firmware has performed all
+	 * necessary relocation fixups for the new virtual addresses.
+	 */
+	efi_runtime_update_mappings();
+	efi_dump_pagetable();
 
 	/*
 	 * We mapped the descriptor array into the EFI pagetable above
diff --git a/arch/x86/platform/efi/efi_32.c b/arch/x86/platform/efi/efi_32.c
index 58d669bc8250..338402b91d2e 100644
--- a/arch/x86/platform/efi/efi_32.c
+++ b/arch/x86/platform/efi/efi_32.c
@@ -90,7 +90,7 @@ void __init efi_call_phys_epilog(pgd_t *save_pgd)
 	__flush_tlb_all();
 }
 
-void __init efi_runtime_mkexec(void)
+void __init efi_runtime_update_mappings(void)
 {
 	if (__supported_pte_mask & _PAGE_NX)
 		runtime_code_page_mkexec();
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index b0965b27e47f..40d2f447a9dd 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -393,13 +393,50 @@ void __init parse_efi_setup(u64 phys_addr, u32 data_len)
 	efi_setup = phys_addr + sizeof(struct setup_data);
 }
 
-void __init efi_runtime_mkexec(void)
+void __init efi_runtime_update_mappings(void)
 {
-	if (!efi_enabled(EFI_OLD_MEMMAP))
+	unsigned long pfn;
+	pgd_t *pgd = efi_pgd;
+	efi_memory_desc_t *md;
+	void *p;
+
+	if (efi_enabled(EFI_OLD_MEMMAP)) {
+		if (__supported_pte_mask & _PAGE_NX)
+			runtime_code_page_mkexec();
+		return;
+	}
+
+	if (!efi_enabled(EFI_NX_PE_DATA))
 		return;
 
-	if (__supported_pte_mask & _PAGE_NX)
-		runtime_code_page_mkexec();
+	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
+		unsigned long pf = 0;
+		md = p;
+
+		if (!(md->attribute & EFI_MEMORY_RUNTIME))
+			continue;
+
+		if (!(md->attribute & EFI_MEMORY_WB))
+			pf |= _PAGE_PCD;
+
+		if ((md->attribute & EFI_MEMORY_XP) ||
+			(md->type == EFI_RUNTIME_SERVICES_DATA))
+			pf |= _PAGE_NX;
+
+		if (!(md->attribute & EFI_MEMORY_RO) &&
+			(md->type != EFI_RUNTIME_SERVICES_CODE))
+			pf |= _PAGE_RW;
+
+		/* Update the 1:1 mapping */
+		pfn = md->phys_addr >> PAGE_SHIFT;
+		if (kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf))
+			pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
+				   md->phys_addr, md->virt_addr);
+
+		if (kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf))
+			pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
+				   md->phys_addr, md->virt_addr);
+	}
 }
 
 void __init efi_dump_pagetable(void)
-- 
2.6.2