Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-24 05:02:12 +00:00
Code Issues Packages Projects Releases Wiki Activity

x86: c_p_a() make it more robust against use of PAT bits

Browse Source 
Use the page table level instead of the PSE bit to check if the PTE
is for a 4K page or not. This makes the code more robust when the PAT
bit is changed because the PAT bit on 4K pages is in the same position
as the PSE bit.

Signed-off-by: Andi Kleen <ak@suse.de>
Acked-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Andi Kleen 2008-01-30 13:33:52 +01:00 committed by Ingo Molnar
parent 3c86882341
commit 895bdc2995
2 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/x86/mm/pageattr_32.c
View File

@ -172,7 +172,7 @@ static int __change_page_attr(struct page *page, pgprot_t prot)
BUG_ON(PageCompound(kpte_page)); BUG_ON(PageCompound(kpte_page));
if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) { if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) {
if (!pte_huge(*kpte)) { if (level == 3) {
set_pte_atomic(kpte, mk_pte(page, prot)); set_pte_atomic(kpte, mk_pte(page, prot));
} else { } else {
struct page *split; struct page *split;
@ -190,7 +190,7 @@ static int __change_page_attr(struct page *page, pgprot_t prot)
} }
page_private(kpte_page)++; page_private(kpte_page)++;
} else { } else {
if (!pte_huge(*kpte)) { if (level == 3) {
set_pte_atomic(kpte, mk_pte(page, PAGE_KERNEL)); set_pte_atomic(kpte, mk_pte(page, PAGE_KERNEL));
BUG_ON(page_private(kpte_page) == 0); BUG_ON(page_private(kpte_page) == 0);
page_private(kpte_page)--; page_private(kpte_page)--;

4
arch/x86/mm/pageattr_64.c
View File

@ -153,7 +153,7 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
BUG_ON(PageLRU(kpte_page)); BUG_ON(PageLRU(kpte_page));
BUG_ON(PageCompound(kpte_page)); BUG_ON(PageCompound(kpte_page));
if (pgprot_val(prot) != pgprot_val(ref_prot)) { if (pgprot_val(prot) != pgprot_val(ref_prot)) {
if (!pte_huge(*kpte)) { if (level == 4) {
set_pte(kpte, pfn_pte(pfn, prot)); set_pte(kpte, pfn_pte(pfn, prot));
} else { } else {
/* /*
@ -172,7 +172,7 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
} }
page_private(kpte_page)++; page_private(kpte_page)++;
} else { } else {
if (!pte_huge(*kpte)) { if (level == 4) {
set_pte(kpte, pfn_pte(pfn, ref_prot)); set_pte(kpte, pfn_pte(pfn, ref_prot));
BUG_ON(page_private(kpte_page) == 0); BUG_ON(page_private(kpte_page) == 0);
page_private(kpte_page)--; page_private(kpte_page)--;