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authorRafael J. Wysocki <rjw@sisk.pl>2007-10-18 03:04:54 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-18 14:37:20 -0700
commitefa4d2fb047b25a6be67fe92178a2a78da6b3f6a (patch)
tree82f2e7bc66d3867fcd4f66c424403d35b9d49812
parentc30bb68c26ad7e9277f2d1dfed8347f329e1cf27 (diff)
downloadop-kernel-dev-efa4d2fb047b25a6be67fe92178a2a78da6b3f6a.zip
op-kernel-dev-efa4d2fb047b25a6be67fe92178a2a78da6b3f6a.tar.gz
Hibernation: Use temporary page tables for kernel text mapping on x86_64
Use temporary page tables for the kernel text mapping during hibernation restore on x86_64. Without the patch, the original boot kernel's page tables that represent the kernel text mapping are used while the core of the image kernel is being restored. However, in principle, if the boot kernel is not identical to the image kernel, the location of these page tables in the image kernel need not be the same, so we should create a safe copy of the kernel text mapping prior to restoring the core of the image kernel. Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Pavel Machek <pavel@ucw.cz> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--arch/x86/kernel/suspend_64.c39
1 files changed, 33 insertions, 6 deletions
diff --git a/arch/x86/kernel/suspend_64.c b/arch/x86/kernel/suspend_64.c
index da10eef..f8fafe5 100644
--- a/arch/x86/kernel/suspend_64.c
+++ b/arch/x86/kernel/suspend_64.c
@@ -197,25 +197,42 @@ static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long en
return 0;
}
+static int res_kernel_text_pud_init(pud_t *pud, unsigned long start)
+{
+ pmd_t *pmd;
+ unsigned long paddr;
+
+ pmd = (pmd_t *)get_safe_page(GFP_ATOMIC);
+ if (!pmd)
+ return -ENOMEM;
+ set_pud(pud + pud_index(start), __pud(__pa(pmd) | _KERNPG_TABLE));
+ for (paddr = 0; paddr < KERNEL_TEXT_SIZE; pmd++, paddr += PMD_SIZE) {
+ unsigned long pe;
+
+ pe = __PAGE_KERNEL_LARGE_EXEC | _PAGE_GLOBAL | paddr;
+ pe &= __supported_pte_mask;
+ set_pmd(pmd, __pmd(pe));
+ }
+
+ return 0;
+}
+
static int set_up_temporary_mappings(void)
{
unsigned long start, end, next;
+ pud_t *pud;
int error;
temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC);
if (!temp_level4_pgt)
return -ENOMEM;
- /* It is safe to reuse the original kernel mapping */
- set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map),
- init_level4_pgt[pgd_index(__START_KERNEL_map)]);
-
/* Set up the direct mapping from scratch */
start = (unsigned long)pfn_to_kaddr(0);
end = (unsigned long)pfn_to_kaddr(end_pfn);
for (; start < end; start = next) {
- pud_t *pud = (pud_t *)get_safe_page(GFP_ATOMIC);
+ pud = (pud_t *)get_safe_page(GFP_ATOMIC);
if (!pud)
return -ENOMEM;
next = start + PGDIR_SIZE;
@@ -226,7 +243,17 @@ static int set_up_temporary_mappings(void)
set_pgd(temp_level4_pgt + pgd_index(start),
mk_kernel_pgd(__pa(pud)));
}
- return 0;
+
+ /* Set up the kernel text mapping from scratch */
+ pud = (pud_t *)get_safe_page(GFP_ATOMIC);
+ if (!pud)
+ return -ENOMEM;
+ error = res_kernel_text_pud_init(pud, __START_KERNEL_map);
+ if (!error)
+ set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map),
+ __pgd(__pa(pud) | _PAGE_TABLE));
+
+ return error;
}
int swsusp_arch_resume(void)
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