try_preserve_large_page() is called from __change_page_attr() to
change the mapping attribute of a given large page. This function
uses pte_pfn() and pte_pgprot() for PUD/PMD, which do not handle
the large PAT bit properly.
Fix try_preserve_large_page() by using the corresponding pud/pmd
prot/pfn interfaces.
Also remove '#ifdef CONFIG_X86_64', which is not necessary.
Signed-off-by: Toshi Kani <toshi.kani@xxxxxxx>
Cc: Juergen Gross <jgross@xxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/mm/pageattr.c | 24 ++++++++++++++----------
1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 023b639..d055557 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -486,7 +486,7 @@ static int
try_preserve_large_page(pte_t *kpte, unsigned long address,
struct cpa_data *cpa)
{
- unsigned long nextpage_addr, numpages, pmask, psize, addr, pfn;
+ unsigned long nextpage_addr, numpages, pmask, psize, addr, pfn, old_pfn;
pte_t new_pte, old_pte, *tmp;
pgprot_t old_prot, new_prot, req_prot;
int i, do_split = 1;
@@ -506,17 +506,21 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
switch (level) {
case PG_LEVEL_2M:
-#ifdef CONFIG_X86_64
+ old_prot = pmd_pgprot(*(pmd_t *)kpte);
+ old_pfn = pmd_pfn(*(pmd_t *)kpte);
+ break;
case PG_LEVEL_1G:
-#endif
- psize = page_level_size(level);
- pmask = page_level_mask(level);
+ old_prot = pud_pgprot(*(pud_t *)kpte);
+ old_pfn = pud_pfn(*(pud_t *)kpte);
break;
default:
do_split = -EINVAL;
goto out_unlock;
}
+ psize = page_level_size(level);
+ pmask = page_level_mask(level);
+
/*
* Calculate the number of pages, which fit into this large
* page starting at address:
@@ -532,7 +536,7 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
* up accordingly.
*/
old_pte = *kpte;
- old_prot = req_prot = pgprot_large_2_4k(pte_pgprot(old_pte));
+ old_prot = req_prot = pgprot_large_2_4k(old_prot);
pgprot_val(req_prot) &= ~pgprot_val(cpa->mask_clr);
pgprot_val(req_prot) |= pgprot_val(cpa->mask_set);
@@ -558,10 +562,10 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
req_prot = canon_pgprot(req_prot);
/*
- * old_pte points to the large page base address. So we need
+ * old_pfn points to the large page base pfn. So we need
* to add the offset of the virtual address:
*/
- pfn = pte_pfn(old_pte) + ((address & (psize - 1)) >> PAGE_SHIFT);
+ pfn = old_pfn + ((address & (psize - 1)) >> PAGE_SHIFT);
cpa->pfn = pfn;
new_prot = static_protections(req_prot, address, pfn);
@@ -572,7 +576,7 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
* the pages in the range we try to preserve:
*/
addr = address & pmask;
- pfn = pte_pfn(old_pte);
+ pfn = old_pfn;
for (i = 0; i < (psize >> PAGE_SHIFT); i++, addr += PAGE_SIZE, pfn++) {
pgprot_t chk_prot = static_protections(req_prot, addr, pfn);
@@ -602,7 +606,7 @@ try_preserve_large_page(pte_t *kpte, unsigned long address,
* The address is aligned and the number of pages
* covers the full page.
*/
- new_pte = pfn_pte(pte_pfn(old_pte), new_prot);
+ new_pte = pfn_pte(old_pfn, new_prot);
__set_pmd_pte(kpte, address, new_pte);
cpa->flags |= CPA_FLUSHTLB;
do_split = 0;
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>