From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicholas Piggin Subject: [RFC PATCH 2/4] mm: mmu_notifier fix for tlb_end_vma Date: Thu, 26 Jul 2018 00:06:39 +1000 Message-ID: <20180725140641.30372-3-npiggin@gmail.com> References: <20180725140641.30372-1-npiggin@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180725140641.30372-1-npiggin@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: linux-mm@kvack.org Cc: linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, Nicholas Piggin 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. --- 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 bc053d5e9d41..135d18b31e44 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-pl0-f67.google.com ([209.85.160.67]:38436 "EHLO mail-pl0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728397AbeGYPSt (ORCPT ); Wed, 25 Jul 2018 11:18:49 -0400 Received: by mail-pl0-f67.google.com with SMTP id b1-v6so3350915pls.5 for ; Wed, 25 Jul 2018 07:06:59 -0700 (PDT) From: Nicholas Piggin Subject: [RFC PATCH 2/4] mm: mmu_notifier fix for tlb_end_vma Date: Thu, 26 Jul 2018 00:06:39 +1000 Message-ID: <20180725140641.30372-3-npiggin@gmail.com> In-Reply-To: <20180725140641.30372-1-npiggin@gmail.com> References: <20180725140641.30372-1-npiggin@gmail.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: linux-mm@kvack.org Cc: Nicholas Piggin , linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org Message-ID: <20180725140639.jt2m1-qgB3Id8v9e_XLx_fzvBaNLl3r8WgPDMem--qQ@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. --- 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 bc053d5e9d41..135d18b31e44 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