From: Joerg Roedel <jroedel@xxxxxxx> With huge-page ioremap areas the unmappings also need to be synced between all page-tables. Otherwise it can cause data corruption when a region is unmapped and later re-used. Make the vmalloc_sync_one() function ready to sync unmappings. Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> --- arch/x86/mm/fault.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 4a4049f6d458..d71e167662c3 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -194,11 +194,12 @@ static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address) pmd = pmd_offset(pud, address); pmd_k = pmd_offset(pud_k, address); - if (!pmd_present(*pmd_k)) - return NULL; - if (!pmd_present(*pmd)) + if (pmd_present(*pmd) ^ pmd_present(*pmd_k)) set_pmd(pmd, *pmd_k); + + if (!pmd_present(*pmd_k)) + return NULL; else BUG_ON(pmd_pfn(*pmd) != pmd_pfn(*pmd_k)); -- 2.17.1
