From fd1102f0aadec7d18792b132e1d224290b2aecca Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Thu, 23 Aug 2018 18:47:09 +1000 Subject: [PATCH] mm: mmu_notifier fix for tlb_end_vma The generic tlb_end_vma does not call invalidate_range mmu notifier, and it resets resets the mmu_gather range, which means the notifier won't be called on part of the range in case of an unmap that spans multiple vmas. ARM64 seems to be the only arch I could see that has notifiers and uses the generic tlb_end_vma. I have not actually tested it. [ Catalin and Will point out that ARM64 currently only uses the notifiers for KVM, which doesn't use the ->invalidate_range() callback right now, so it's a bug, but one that happens to not affect them. So not necessary for stable. - Linus ] Signed-off-by: Nicholas Piggin Acked-by: Catalin Marinas Acked-by: Will Deacon Signed-off-by: Linus Torvalds --- include/asm-generic/tlb.h | 17 +++++++++++++---- mm/memory.c | 10 ---------- 2 files changed, 13 insertions(+), 14 deletions(-) diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index 3063125197ad..b3353e21f3b3 100644 --- a/include/asm-generic/tlb.h +++ b/include/asm-generic/tlb.h @@ -15,6 +15,7 @@ #ifndef _ASM_GENERIC__TLB_H #define _ASM_GENERIC__TLB_H +#include #include #include #include @@ -138,6 +139,16 @@ static inline void __tlb_reset_range(struct mmu_gather *tlb) } } +static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) +{ + if (!tlb->end) + return; + + tlb_flush(tlb); + mmu_notifier_invalidate_range(tlb->mm, tlb->start, tlb->end); + __tlb_reset_range(tlb); +} + static inline void tlb_remove_page_size(struct mmu_gather *tlb, struct page *page, int page_size) { @@ -186,10 +197,8 @@ static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb, #define __tlb_end_vma(tlb, vma) \ do { \ - if (!tlb->fullmm && tlb->end) { \ - tlb_flush(tlb); \ - __tlb_reset_range(tlb); \ - } \ + if (!tlb->fullmm) \ + tlb_flush_mmu_tlbonly(tlb); \ } while (0) #ifndef tlb_end_vma diff --git a/mm/memory.c b/mm/memory.c index 8b3442979855..3ff4394a2e1b 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -238,16 +238,6 @@ void arch_tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm, __tlb_reset_range(tlb); } -static void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) -{ - if (!tlb->end) - return; - - tlb_flush(tlb); - mmu_notifier_invalidate_range(tlb->mm, tlb->start, tlb->end); - __tlb_reset_range(tlb); -} - static void tlb_flush_mmu_free(struct mmu_gather *tlb) { struct mmu_gather_batch *batch;