From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicholas Piggin Subject: [RFC PATCH 2/2] mm: mmu_notifier fix for tlb_end_vma Date: Thu, 23 Aug 2018 18:47:09 +1000 Message-ID: <20180823084709.19717-3-npiggin@gmail.com> References: <20180823084709.19717-1-npiggin@gmail.com> Return-path: In-Reply-To: <20180823084709.19717-1-npiggin@gmail.com> Sender: linux-kernel-owner@vger.kernel.org To: Peter Zijlstra Cc: Nicholas Piggin , torvalds@linux-foundation.org, luto@kernel.org, x86@kernel.org, bp@alien8.de, will.deacon@arm.com, riel@surriel.com, jannh@google.com, ascannell@google.com, dave.hansen@intel.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, David Miller , Martin Schwidefsky , Michael Ellerman , linux-arch@vger.kernel.org List-Id: linux-arch.vger.kernel.org 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. Signed-off-by: Nicholas Piggin --- 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 e811ef7b8350..79cb76b89c26 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 7c58310734eb..c4a7b6cb17c8 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; -- 2.17.0 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f195.google.com ([209.85.210.195]:42928 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728527AbeHWMQL (ORCPT ); Thu, 23 Aug 2018 08:16:11 -0400 From: Nicholas Piggin Subject: [RFC PATCH 2/2] mm: mmu_notifier fix for tlb_end_vma Date: Thu, 23 Aug 2018 18:47:09 +1000 Message-ID: <20180823084709.19717-3-npiggin@gmail.com> In-Reply-To: <20180823084709.19717-1-npiggin@gmail.com> References: <20180823084709.19717-1-npiggin@gmail.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Peter Zijlstra Cc: Nicholas Piggin , torvalds@linux-foundation.org, luto@kernel.org, x86@kernel.org, bp@alien8.de, will.deacon@arm.com, riel@surriel.com, jannh@google.com, ascannell@google.com, dave.hansen@intel.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, David Miller , Martin Schwidefsky , Michael Ellerman , linux-arch@vger.kernel.org Message-ID: <20180823084709.1wgoDeY1IiwiUTkm5YzDy7wqFJlkWffKvRVFZKoW7SQ@z> 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. Signed-off-by: Nicholas Piggin --- 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 e811ef7b8350..79cb76b89c26 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 7c58310734eb..c4a7b6cb17c8 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; -- 2.17.0