From patchwork Wed Jul 12 04:33:08 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hugh Dickins X-Patchwork-Id: 1806583 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=2404:9400:2:0:216:3eff:fee1:b9f1; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20221208 header.b=oKpaowvQ; dkim-atps=neutral Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2404:9400:2:0:216:3eff:fee1:b9f1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4R14cb2nBGz20ZZ for ; Wed, 12 Jul 2023 14:33:35 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20221208 header.b=oKpaowvQ; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4R14cb1t72z3cH2 for ; Wed, 12 Jul 2023 14:33:35 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.a=rsa-sha256 header.s=20221208 header.b=oKpaowvQ; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=google.com (client-ip=2607:f8b0:4864:20::b2e; helo=mail-yb1-xb2e.google.com; envelope-from=hughd@google.com; receiver=lists.ozlabs.org) Received: from mail-yb1-xb2e.google.com (mail-yb1-xb2e.google.com [IPv6:2607:f8b0:4864:20::b2e]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4R14cG3RvRz304g for ; Wed, 12 Jul 2023 14:33:17 +1000 (AEST) Received: by mail-yb1-xb2e.google.com with SMTP id 3f1490d57ef6-c01e1c0402cso5788263276.0 for ; Tue, 11 Jul 2023 21:33:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1689136394; x=1691728394; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:from:to:cc:subject:date:message-id:reply-to; bh=QJ3N9RNUACQk0rp/xTQEOUK2bEy9LceuxJNDbuu7Hdo=; b=oKpaowvQeaQUncOOMCvTBHmXQ/FtZl+zZp5+Fo04CzoCy9LRKSCy43wNQCF2w2abHG jYi2GRVb9SUA+cOJwBdOtClSXiZ2Z7OrQDz8b0C3ZKWCpyBSxxh9g0MDPDTlwWm1wpni MQq6dZQMaat5mVW33VG/Z/sJCOzOtM5JcugYkrHF0OjaZarDla2EabzCECYeLkptPTFA kvVOAdnkA+dARAIwQYkZ5QFG5BKKdFwsILzvRn8L6hIPQtsvNfCEpljLsKMHiBJ7Tb9i vvB9S1uM8vmPWQ9MN4Bos/RgNtKXVdLVIPeeQrun3EY+oUKy7MowWj11CHLrlgzQNYzJ ikwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689136394; x=1691728394; h=mime-version:references:message-id:in-reply-to:subject:cc:to:from :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=QJ3N9RNUACQk0rp/xTQEOUK2bEy9LceuxJNDbuu7Hdo=; b=Pr9UdOWijtkNO+gt1GY1NVuXUMvs4rw0oBvPzkjIg2yGjlkeKtJxyhgalfCXEj0TsX jYz9aR/qGx3trV4M2x+3tyrUISxTyIF9mh5iOMADvAwvmn6WPRDWa/ecq7bjRoHNhcUk retzIyuo5CZZJkPw0HkCIK4pE1SG6F8Sd/vfqFhc4gzQhyj0EVuylj2vrfRstDLS5DES y2Co7rgacNBi6euSVc/WQQwx2H7wtFNNAx5pQbvyZHr1oHao3KuK0dTCoRn25+su/AaO C8WUYdcoUi7+y4xDtv5drodmniK29j4j098xYjLYWrrX1j3H55jKyFisLgMTP0z5OB17 5j7g== X-Gm-Message-State: ABy/qLafPkTtz/lSbvi5E+9Vk9+f/PDNlRalXlNJPFSEG/YNXu1QXvl8 iOTN3hQagLIfDbMgpMNXkGmhkA== X-Google-Smtp-Source: APBJJlHtqAOgfTEvtz6FEYsO4J7wfUGe8UB05ARnUaznX7yxHAtr1BNRbw9aWEHw4YhpidgoA6BFwQ== X-Received: by 2002:a5b:70d:0:b0:c01:308a:44f2 with SMTP id g13-20020a5b070d000000b00c01308a44f2mr13992957ybq.57.1689136393735; Tue, 11 Jul 2023 21:33:13 -0700 (PDT) Received: from ripple.attlocal.net (172-10-233-147.lightspeed.sntcca.sbcglobal.net. [172.10.233.147]) by smtp.gmail.com with ESMTPSA id b8-20020a252e48000000b00c61af359b15sm751502ybn.43.2023.07.11.21.33.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Jul 2023 21:33:13 -0700 (PDT) Date: Tue, 11 Jul 2023 21:33:08 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@ripple.attlocal.net To: Andrew Morton Subject: [PATCH v3 03/13] arm: adjust_pte() use pte_offset_map_nolock() In-Reply-To: <7cd843a9-aa80-14f-5eb2-33427363c20@google.com> Message-ID: <4d5258bd-ffa0-018-253a-25f2c9b783f7@google.com> References: <7cd843a9-aa80-14f-5eb2-33427363c20@google.com> MIME-Version: 1.0 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Miaohe Lin , David Hildenbrand , Peter Zijlstra , Yang Shi , Peter Xu , linux-kernel@vger.kernel.org, Song Liu , sparclinux@vger.kernel.org, Alexander Gordeev , Claudio Imbrenda , Will Deacon , linux-s390@vger.kernel.org, Yu Zhao , Ira Weiny , Alistair Popple , Russell King , Matthew Wilcox , Steven Price , Christoph Hellwig , Jason Gunthorpe , "Aneesh Kumar K.V" , Zi Yan , Huang Ying , Axel Rasmussen , Gerald Schaefer , Christian Borntraeger , Thomas Hellstrom , Ralph Campbell , Pasha Tatashin , Vasily Gorbik , Anshuman Khandual , Heiko Carstens , Qi Zheng , Suren Baghdasaryan , Vlastimil Babka , linux-arm-kernel@lists.infradead.org, SeongJae Park , Lorenzo Stoakes , Jann Horn , linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, Naoya Horiguchi , Zack Rusin , Vishal Moola , Minchan Kim , "Kirill A. Shutemov" , Mel Gorman , "David S. Miller" , Mike Rapoport , Mike Kravetz Errors-To: linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Instead of pte_lockptr(), use the recently added pte_offset_map_nolock() in adjust_pte(): because it gives the not-locked ptl for precisely that pte, which the caller can then safely lock; whereas pte_lockptr() is not so tightly coupled, because it dereferences the pmd pointer again. Signed-off-by: Hugh Dickins --- arch/arm/mm/fault-armv.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c index ca5302b0b7ee..7cb125497976 100644 --- a/arch/arm/mm/fault-armv.c +++ b/arch/arm/mm/fault-armv.c @@ -117,11 +117,10 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address, * must use the nested version. This also means we need to * open-code the spin-locking. */ - pte = pte_offset_map(pmd, address); + pte = pte_offset_map_nolock(vma->vm_mm, pmd, address, &ptl); if (!pte) return 0; - ptl = pte_lockptr(vma->vm_mm, pmd); do_pte_lock(ptl); ret = do_adjust_pte(vma, address, pfn, pte);