slow_virt_to_phys() calls lookup_address() to obtain *pte and
its level. It then calls pte_pfn() to obtain a physical address
for any level. However, this physical address is not correct
when the large PAT bit is set because pte_pfn() does not mask
the large PAT bit properly for PUD/PMD.
Fix slow_virt_to_phys() to use pud_pfn() and pmd_pfn() for 1GB
and 2MB mapping levels.
Signed-off-by: Toshi Kani <toshi.kani@xxxxxx>
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, 17 insertions(+), 7 deletions(-)
diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index b6c2659..023b639 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -415,18 +415,28 @@ pmd_t *lookup_pmd_address(unsigned long address)
phys_addr_t slow_virt_to_phys(void *__virt_addr)
{
unsigned long virt_addr = (unsigned long)__virt_addr;
- phys_addr_t phys_addr;
- unsigned long offset;
+ unsigned long phys_addr, offset;
enum pg_level level;
- unsigned long pmask;
pte_t *pte;
pte = lookup_address(virt_addr, &level);
BUG_ON(!pte);
- pmask = page_level_mask(level);
- offset = virt_addr & ~pmask;
- phys_addr = (phys_addr_t)pte_pfn(*pte) << PAGE_SHIFT;
- return (phys_addr | offset);
+
+ switch (level) {
+ case PG_LEVEL_1G:
+ phys_addr = pud_pfn(*(pud_t *)pte) << PAGE_SHIFT;
+ offset = virt_addr & ~PUD_PAGE_MASK;
+ break;
+ case PG_LEVEL_2M:
+ phys_addr = pmd_pfn(*(pmd_t *)pte) << PAGE_SHIFT;
+ offset = virt_addr & ~PMD_PAGE_MASK;
+ break;
+ default:
+ phys_addr = pte_pfn(*pte) << PAGE_SHIFT;
+ offset = virt_addr & ~PAGE_MASK;
+ }
+
+ return (phys_addr_t)(phys_addr | offset);
}
EXPORT_SYMBOL_GPL(slow_virt_to_phys);
--
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