From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E11C2C4321D for ; Thu, 23 Aug 2018 13:41:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 90797208FE for ; Thu, 23 Aug 2018 13:41:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 90797208FE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731522AbeHWRKz (ORCPT ); Thu, 23 Aug 2018 13:10:55 -0400 Received: from foss.arm.com ([217.140.101.70]:46652 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730895AbeHWRKy (ORCPT ); Thu, 23 Aug 2018 13:10:54 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 64D74ED1; Thu, 23 Aug 2018 06:41:09 -0700 (PDT) Received: from brain-police (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E9CA63F675; Thu, 23 Aug 2018 06:41:07 -0700 (PDT) Date: Thu, 23 Aug 2018 14:41:05 +0100 From: Will Deacon To: Nicholas Piggin Cc: Peter Zijlstra , torvalds@linux-foundation.org, luto@kernel.org, x86@kernel.org, bp@alien8.de, 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 Subject: Re: [RFC PATCH 2/2] mm: mmu_notifier fix for tlb_end_vma Message-ID: <20180823134104.GD1496@brain-police> References: <20180823084709.19717-1-npiggin@gmail.com> <20180823084709.19717-3-npiggin@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180823084709.19717-3-npiggin@gmail.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 23, 2018 at 06:47:09PM +1000, Nicholas Piggin wrote: > 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(-) I think we only use the notifiers in the KVM code, which appears to leave the ->invalidate_range() callback empty, so that at least explains why we haven't run into problems here. But the change looks correct to me, so: Acked-by: Will Deacon Thanks, Will