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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 A7820C64E7B for ; Fri, 20 Nov 2020 14:36:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5EC432224C for ; Fri, 20 Nov 2020 14:36:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="afgeTZc4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728175AbgKTOgV (ORCPT ); Fri, 20 Nov 2020 09:36:21 -0500 Received: from mail.kernel.org ([198.145.29.99]:34088 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727784AbgKTOgU (ORCPT ); Fri, 20 Nov 2020 09:36:20 -0500 Received: from localhost.localdomain (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7948B2224C; Fri, 20 Nov 2020 14:36:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605882979; bh=Cx43nH7+0p7dCMlh2hWC5+4DOrQsHy/9+cM/6j7sA0k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=afgeTZc4tCjR0MOdMgoK69uQiEsqDnC9K0pzMB5Sj80IghTT6RiSH0yixLei86pAh eA3sUhCiS98J5br6nm+aCIY5W8YWvOl3cFeDFnuwN33agaWXZXHtRo46DvLXqEmIYl oudAEy1bh7kfEsjFKdgb8jP7qkR0efezAG0Z/UKY= From: Will Deacon To: linux-kernel@vger.kernel.org Cc: kernel-team@android.com, Will Deacon , Catalin Marinas , Yu Zhao , Minchan Kim , Peter Zijlstra , Linus Torvalds , Anshuman Khandual , linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH 6/6] mm: proc: Avoid fullmm flush for young/dirty bit toggling Date: Fri, 20 Nov 2020 14:35:57 +0000 Message-Id: <20201120143557.6715-7-will@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20201120143557.6715-1-will@kernel.org> References: <20201120143557.6715-1-will@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org clear_refs_write() uses the 'fullmm' API for invalidating TLBs after updating the page-tables for the current mm. However, since the mm is not being freed, this can result in stale TLB entries on architectures which elide 'fullmm' invalidation. Ensure that TLB invalidation is performed after updating soft-dirty entries via clear_refs_write() by using the non-fullmm API to MMU gather. Signed-off-by: Will Deacon --- fs/proc/task_mmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index a76d339b5754..316af047f1aa 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1238,7 +1238,7 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf, count = -EINTR; goto out_mm; } - tlb_gather_mmu_fullmm(&tlb, mm); + tlb_gather_mmu(&tlb, mm, 0, TASK_SIZE); if (type == CLEAR_REFS_SOFT_DIRTY) { for (vma = mm->mmap; vma; vma = vma->vm_next) { if (!(vma->vm_flags & VM_SOFTDIRTY)) -- 2.29.2.454.gaff20da3a2-goog