From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Pavel Machek <pavel@ucw.cz>
Cc: LKML <linux-kernel@vger.kernel.org>, Andi Kleen <ak@suse.de>,
Andrew Morton <akpm@osdl.org>
Subject: [PATCH][Fix] Prevent swsusp from corrupting page translation tables during resume on x86-64
Date: Sat, 24 Sep 2005 19:36:11 +0200 [thread overview]
Message-ID: <200509241936.12214.rjw@sisk.pl> (raw)
[The previous message has been sent accidentally without the patch]
Hi,
The following patch fixes Bug #4959. It creates temporary page translation
tables located in the page frames that are not overwritten by swsusp while copying
the image.
The temporary page translation tables are generally based on the existing ones
with the exception that the mappings using 4KB pages are replaced with the
equivalent mappings that use 2MB pages only. The temporary page tables are
only used for copying the image.
Please consider for applying.
Greetings,
Rafael
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Index: linux-2.6.14-rc2-git3/arch/x86_64/kernel/suspend.c
===================================================================
--- linux-2.6.14-rc2-git3.orig/arch/x86_64/kernel/suspend.c 2005-09-23 18:20:41.000000000 +0200
+++ linux-2.6.14-rc2-git3/arch/x86_64/kernel/suspend.c 2005-09-23 18:21:48.000000000 +0200
@@ -11,6 +11,17 @@
#include <linux/smp.h>
#include <linux/suspend.h>
#include <asm/proto.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+
+/* Defined in kernel/power/swsusp.c */
+extern unsigned long get_usable_page(unsigned gfp_mask);
+
+pgd_t *temp_level4_pgt;
+
+#define __PGTABLE_MASK 0x000ffffffffff000UL
+#define __PGTABLE_PSE_MASK 0x000fffffffe00000UL
struct saved_context saved_context;
@@ -140,4 +151,69 @@
}
+static int __duplicate_page_tables(pgd_t *src_pgd, pgd_t *pgd, unsigned long map_offset)
+{
+ pud_t *src_pud, *pud;
+ pmd_t *src_pmd, *pmd;
+ pte_t *src_pte;
+ int i, j, k;
+
+ pr_debug("Duplicating pagetables for the map 0x%016lx at 0x%016lx\n",
+ map_offset, (unsigned long)src_pgd);
+ i = pgd_index(map_offset);
+ j = pud_index(map_offset);
+ k = pmd_index(map_offset);
+ src_pgd += i;
+ pgd += i;
+ for (; pgd_val(*src_pgd) && i < PTRS_PER_PGD; i++, src_pgd++, pgd++) {
+ pud = (pud_t *)get_usable_page(GFP_ATOMIC);
+ if (!pud)
+ return -ENOMEM;
+ pgd_val(*pgd) = (pgd_val(*src_pgd) & ~__PGTABLE_MASK) |
+ __pa((unsigned long)pud);
+ pud += j;
+ src_pud = (pud_t *)__va(pgd_val(*src_pgd) & __PGTABLE_MASK) + j;
+ for (; pud_val(*src_pud) && j < PTRS_PER_PUD; j++, src_pud++, pud++) {
+ pmd = (pmd_t *)get_usable_page(GFP_ATOMIC);
+ if (!pmd)
+ return -ENOMEM;
+ pud_val(*pud) = (pud_val(*src_pud) & ~__PGTABLE_MASK) |
+ __pa((unsigned long)pmd);
+ pmd += k;
+ src_pmd = (pmd_t *)__va(pud_val(*src_pud) & __PGTABLE_MASK) + k;
+ for (; pmd_val(*src_pmd) && k < PTRS_PER_PMD; k++, src_pmd++, pmd++)
+ if (pmd_val(*src_pmd) & _PAGE_PSE) /* 2MB page */
+ pmd_val(*pmd) = pmd_val(*src_pmd);
+ else { /* 4KB page table -> 2MB page */
+ src_pte = __va(pmd_val(*src_pmd) & __PGTABLE_MASK);
+ pmd_val(*pmd) = ((pmd_val(*src_pmd) & ~__PGTABLE_MASK) |
+ _PAGE_PSE) |
+ (pte_val(*src_pte) & __PGTABLE_PSE_MASK);
+ }
+ k = 0;
+ }
+ j = 0;
+ }
+ return 0;
+}
+void duplicate_page_tables(void)
+{
+ int result = 0;
+
+ temp_level4_pgt = (pgd_t *)get_usable_page(GFP_ATOMIC);
+
+ if (!temp_level4_pgt)
+ result = -ENOMEM;
+
+ if (!result)
+ result = __duplicate_page_tables(init_level4_pgt, temp_level4_pgt,
+ PAGE_OFFSET);
+
+ if (!result)
+ result = __duplicate_page_tables(init_level4_pgt, temp_level4_pgt,
+ __START_KERNEL_map);
+
+ if (result)
+ panic("No room for temporary page translation tables!\n");
+}
Index: linux-2.6.14-rc2-git3/kernel/power/swsusp.c
===================================================================
--- linux-2.6.14-rc2-git3.orig/kernel/power/swsusp.c 2005-09-23 18:20:41.000000000 +0200
+++ linux-2.6.14-rc2-git3/kernel/power/swsusp.c 2005-09-23 18:21:48.000000000 +0200
@@ -1092,7 +1092,7 @@
*eaten_memory = c;
}
-static unsigned long get_usable_page(unsigned gfp_mask)
+unsigned long get_usable_page(unsigned gfp_mask)
{
unsigned long m;
@@ -1478,11 +1478,12 @@
/* Allocate memory for the image and read the data from swap */
error = check_pagedir(pagedir_nosave);
- free_eaten_memory();
+
if (!error)
error = data_read(pagedir_nosave);
if (error) { /* We fail cleanly */
+ free_eaten_memory();
for_each_pbe (p, pagedir_nosave)
if (p->address) {
free_page(p->address);
Index: linux-2.6.14-rc2-git3/arch/x86_64/kernel/suspend_asm.S
===================================================================
--- linux-2.6.14-rc2-git3.orig/arch/x86_64/kernel/suspend_asm.S 2005-09-23 18:20:41.000000000 +0200
+++ linux-2.6.14-rc2-git3/arch/x86_64/kernel/suspend_asm.S 2005-09-23 18:21:48.000000000 +0200
@@ -40,11 +40,14 @@
ret
ENTRY(swsusp_arch_resume)
- /* set up cr3 */
- leaq init_level4_pgt(%rip),%rax
- subq $__START_KERNEL_map,%rax
- movq %rax,%cr3
+ call duplicate_page_tables
+ /* switch to temporary page tables */
+ movq $__PAGE_OFFSET, %rdx
+ movq temp_level4_pgt(%rip), %rax
+ subq %rdx, %rax
+ movq %rax, %cr3
+ /* Flush TLB */
movq mmu_cr4_features(%rip), %rax
movq %rax, %rdx
andq $~(1<<7), %rdx # PGE
@@ -69,6 +72,10 @@
movq pbe_next(%rdx), %rdx
jmp loop
done:
+ /* go back to the original page tables */
+ leaq init_level4_pgt(%rip), %rax
+ subq $__START_KERNEL_map, %rax
+ movq %rax, %cr3
/* Flush TLB, including "global" things (vmalloc) */
movq mmu_cr4_features(%rip), %rax
movq %rax, %rdx
--
- Would you tell me, please, which way I ought to go from here?
- That depends a good deal on where you want to get to.
-- Lewis Carroll "Alice's Adventures in Wonderland"
next reply other threads:[~2005-09-24 17:35 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-09-24 17:36 Rafael J. Wysocki [this message]
2005-09-25 22:07 ` [PATCH][Fix] Prevent swsusp from corrupting page translation tables during resume on x86-64 Pavel Machek
2005-09-26 10:46 ` Rafael J. Wysocki
2005-09-26 10:49 ` Pavel Machek
2005-09-27 8:07 ` [PATCH][Fix] Fix Bug #4959 (take 2) Rafael J. Wysocki
2005-09-27 13:32 ` Pavel Machek
2005-09-27 21:00 ` Rafael J. Wysocki
2005-09-27 21:08 ` Pavel Machek
2005-09-27 23:26 ` Rafael J. Wysocki
2005-09-27 23:43 ` Pavel Machek
2005-09-28 8:25 ` Rafael J. Wysocki
2005-09-28 10:29 ` [PATCH][Fix] Fix Bug #4959 (take 3) Rafael J. Wysocki
-- strict thread matches above, loose matches on Subject: below --
2005-09-24 17:34 [PATCH][Fix] Prevent swsusp from corrupting page translation tables during resume on x86-64 Rafael J. Wysocki
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=200509241936.12214.rjw@sisk.pl \
--to=rjw@sisk.pl \
--cc=ak@suse.de \
--cc=akpm@osdl.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pavel@ucw.cz \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).