[GIT PULL] x86 fixes

Ingo Molnar
2011-03-22T10:20:50Z

Linus,

Please pull the latest x86-fixes-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip.git x86-fixes-for-linus

Thanks,

Ingo

------------------>
Stefano Stabellini (2):
xen: set max_pfn_mapped to the last pfn mapped
xen: update mask_rw_pte after kernel page tables init changes

Yinghai Lu (1):
x86: Cleanup highmap after brk is concluded

arch/x86/kernel/head64.c | 3 ---
arch/x86/kernel/setup.c | 25 +++----------------------
arch/x86/mm/init_64.c | 11 ++++++-----
arch/x86/xen/mmu.c | 21 ++++++++++++---------
4 files changed, 21 insertions(+), 39 deletions(-)

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 2d2673c..5655c22 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -77,9 +77,6 @@ void __init x86_64_start_kernel(char * real_mode_data)
/* Make NULL pointers segfault */
zap_identity_mappings();

- /* Cleanup the over mapped high alias */
- cleanup_highmap();
-
max_pfn_mapped = KERNEL_IMAGE_SIZE >> PAGE_SHIFT;

for (i = 0; i < NUM_EXCEPTION_VECTORS; i++) {
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index b176f2b..4a52a5f 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -294,30 +294,11 @@ static void __init init_gbpages(void)
else
direct_gbpages = 0;
}
-
-static void __init cleanup_highmap_brk_end(void)
-{
- pud_t *pud;
- pmd_t *pmd;
-
- mmu_cr4_features = read_cr4();
-
- /*
- * _brk_end cannot change anymore, but it and _end may be
- * located on different 2M pages. cleanup_highmap(), however,
- * can only consider _end when it runs, so destroy any
- * mappings beyond _brk_end here.
- */
- pud = pud_offset(pgd_offset_k(_brk_end), _brk_end);
- pmd = pmd_offset(pud, _brk_end - 1);
- while (++pmd <= pmd_offset(pud, (unsigned long)_end - 1))
- pmd_clear(pmd);
-}
#else
static inline void init_gbpages(void)
{
}
-static inline void cleanup_highmap_brk_end(void)
+static void __init cleanup_highmap(void)
{
}
#endif
@@ -330,8 +311,6 @@ static void __init reserve_brk(void)
/* Mark brk area as locked down and no longer taking any
new allocations */
_brk_start = 0;
-
- cleanup_highmap_brk_end();
}

#ifdef CONFIG_BLK_DEV_INITRD
@@ -950,6 +929,8 @@ void __init setup_arch(char **cmdline_p)
*/
reserve_brk();

+ cleanup_highmap();
+
memblock.current_limit = get_max_mapped();
memblock_x86_fill();

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index a08a62c..7026505 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -51,6 +51,7 @@
#include <asm/numa.h>
#include <asm/cacheflush.h>
#include <asm/init.h>
+#include <asm/setup.h>

static int __init parse_direct_gbpages_off(char *arg)
{
@@ -293,18 +294,18 @@ void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
* to the compile time generated pmds. This results in invalid pmds up
* to the point where we hit the physaddr 0 mapping.
*
- * We limit the mappings to the region from _text to _end. _end is
- * rounded up to the 2MB boundary. This catches the invalid pmds as
+ * We limit the mappings to the region from _text to _brk_end. _brk_end
+ * is rounded up to the 2MB boundary. This catches the invalid pmds as
* well, as they are located before _text:
*/
void __init cleanup_highmap(void)
{
unsigned long vaddr = __START_KERNEL_map;
- unsigned long end = roundup((unsigned long)_end, PMD_SIZE) - 1;
+ unsigned long vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
+ unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
pmd_t *pmd = level2_kernel_pgt;
- pmd_t *last_pmd = pmd + PTRS_PER_PMD;

- for (; pmd < last_pmd; pmd++, vaddr += PMD_SIZE) {
+ for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
if (pmd_none(*pmd))
continue;
if (vaddr < (unsigned long) _text || vaddr > end)
diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index a2d78ad..21058ad 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1488,10 +1488,12 @@ static __init pte_t mask_rw_pte(pte_t *ptep, pte_t pte)
/*
* If the new pfn is within the range of the newly allocated
* kernel pagetable, and it isn't being mapped into an
- * early_ioremap fixmap slot, make sure it is RO.
+ * early_ioremap fixmap slot as a freshly allocated page, make sure
+ * it is RO.
*/
- if (!is_early_ioremap_ptep(ptep) &&
- pfn >= pgt_buf_start && pfn < pgt_buf_end)
+ if (((!is_early_ioremap_ptep(ptep) &&
+ pfn >= pgt_buf_start && pfn < pgt_buf_end)) ||
+ (is_early_ioremap_ptep(ptep) && pfn != (pgt_buf_end - 1)))
pte = pte_wrprotect(pte);

return pte;
@@ -1701,9 +1703,6 @@ static __init void xen_map_identity_early(pmd_t *pmd, unsigned long max_pfn)
for (pteidx = 0; pteidx < PTRS_PER_PTE; pteidx++, pfn++) {
pte_t pte;

- if (pfn > max_pfn_mapped)
- max_pfn_mapped = pfn;
-
if (!pte_none(pte_page[pteidx]))
continue;

@@ -1761,6 +1760,12 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
pud_t *l3;
pmd_t *l2;

+ /* max_pfn_mapped is the last pfn mapped in the initial memory
+ * mappings. Considering that on Xen after the kernel mappings we
+ * have the mappings of some pages that don't exist in pfn space, we
+ * set max_pfn_mapped to the last real pfn mapped. */
+ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));
+
/* Zap identity mapping */
init_level4_pgt[0] = __pgd(0);

@@ -1865,9 +1870,7 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
initial_kernel_pmd =
extend_brk(sizeof(pmd_t) * PTRS_PER_PMD, PAGE_SIZE);

- max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->pt_base) +
- xen_start_info->nr_pt_frames * PAGE_SIZE +
- 512*1024);
+ max_pfn_mapped = PFN_DOWN(__pa(xen_start_info->mfn_list));

kernel_pmd = m2v(pgd[KERNEL_PGD_BOUNDARY].pgd);
memcpy(initial_kernel_pmd, kernel_pmd, sizeof(pmd_t) * PTRS_PER_PMD);