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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88F7BC77B7D for ; Wed, 10 May 2023 14:29:22 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EF3966B0071; Wed, 10 May 2023 10:29:21 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E7D986B0072; Wed, 10 May 2023 10:29:21 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D1E026B0074; Wed, 10 May 2023 10:29:21 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id BF0206B0071 for ; Wed, 10 May 2023 10:29:21 -0400 (EDT) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 138B9A0AD5 for ; Wed, 10 May 2023 14:29:21 +0000 (UTC) X-FDA: 80774578122.09.E94E10F Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf28.hostedemail.com (Postfix) with ESMTP id 09068C000C for ; Wed, 10 May 2023 14:29:16 +0000 (UTC) Authentication-Results: imf28.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=J+4jUhNT; spf=none (imf28.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1683728958; a=rsa-sha256; cv=none; b=bP8V2fL0meg1JpUJTInn1TolJGCKdLFiN5VlZINkCAqKsTGK3ucM5PbZQbT3BiHFd3wlAe ZzM6iiLCXloE4iiFaF+gxp8Fev+tjko2BH/ataYHZp0eK1YjIQYxJevE83szrvUEvQ4CGj Tfj2WR6TSznYPNB6TzGskZHt8mWmM94= ARC-Authentication-Results: i=1; imf28.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=J+4jUhNT; spf=none (imf28.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1683728958; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=0EAFzv3D+ig/t/nW/DBfVu2XVoT+oGbKuJj55OeG29M=; b=oEeG4QXO++8Znze4WfeIxqrIHrUYr3but//yEVCXxwIGn8DdEYLggbv3/3OGYKFCLF6hT8 wM6svg2S/jxWyNsf9ZXWmNZj5wk2McRGxLzZ1BGhtW5eblCgXaGXHdLeOH+Li2/J15AN+L kDm+1SoFv3id+78CBinLH8w2tRUG874= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=0EAFzv3D+ig/t/nW/DBfVu2XVoT+oGbKuJj55OeG29M=; b=J+4jUhNTtkgBR910a6YalNIyQ+ tt7U4hJdy6/bMnMRbFwUw4R4BOb9+0Ff7LBDou+Og9xKtj0LUO5AFBoRSCgVZj6V+4qtI9NyO+aLD J+qjeNazYGOp2poJgBAbE4T+zzFcK94zyBMyR8CEKCOWF6cZAD/ckf9pamcyX2TCx2Ds1nYIcgMv4 YwsUAYvAhR/VyVizekBBVt5RjwAmWL6n6bn9uhJBLmsIUjhW9TzXC+zhdjEhoglla7XqgWkvmQMCI U8Nml81DpOIGaOe2vCw/lngSxUt99AwWBsoMpyB54WFVQZj7RLyKtPpikab//45hM66bSiwHTonbF W1J90mZw==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1pwknd-00GM7E-9H; Wed, 10 May 2023 14:28:13 +0000 Date: Wed, 10 May 2023 15:28:13 +0100 From: Matthew Wilcox To: Hugh Dickins Cc: Andrew Morton , Mike Kravetz , Mike Rapoport , "Kirill A. Shutemov" , David Hildenbrand , Suren Baghdasaryan , Qi Zheng , Russell King , Catalin Marinas , Will Deacon , Geert Uytterhoeven , Greg Ungerer , Michal Simek , Thomas Bogendoerfer , Helge Deller , John David Anglin , "Aneesh Kumar K.V" , Michael Ellerman , Alexandre Ghiti , Palmer Dabbelt , Heiko Carstens , Christian Borntraeger , Claudio Imbrenda , John Paul Adrian Glaubitz , "David S. Miller" , Chris Zankel , Max Filippov , x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 01/23] arm: allow pte_offset_map[_lock]() to fail Message-ID: References: <77a5d8c-406b-7068-4f17-23b7ac53bc83@google.com> <5011977-d876-6a24-a3fc-c7e6a02877b8@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5011977-d876-6a24-a3fc-c7e6a02877b8@google.com> X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 09068C000C X-Stat-Signature: ri8hcctx9e6s3mwezwpkpoifdi4yq571 X-HE-Tag: 1683728956-628014 X-HE-Meta: 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 PhddhC0C tlGoB8x5kHTuK3zzAg58L4ABk31vWX4yKMg16txzWxUqbYd3JU+D/7y1M0g8xjk0qxtEJCJjdwFIJZQZJJl/5AAYgW4j532YxmBQ6vNtRS5nN1VDI+48JlXBiN/zk2snXXpoJ+NzFpNJWhdy4L4hlQjFtjnpYG1sLw6fPS3KVP13Eo/cMGIab5Pi45+ysp3Ib/vYNUZR8YOwE1YwR5Zk67skmSQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, May 09, 2023 at 09:42:44PM -0700, Hugh Dickins wrote: > diff --git a/arch/arm/lib/uaccess_with_memcpy.c b/arch/arm/lib/uaccess_with_memcpy.c > index e4c2677cc1e9..2f6163f05e93 100644 > --- a/arch/arm/lib/uaccess_with_memcpy.c > +++ b/arch/arm/lib/uaccess_with_memcpy.c > @@ -74,6 +74,9 @@ pin_page_for_write(const void __user *_addr, pte_t **ptep, spinlock_t **ptlp) > return 0; > > pte = pte_offset_map_lock(current->mm, pmd, addr, &ptl); > + if (unlikely(!pte)) > + return 0; Failing seems like the wrong thig to do if we transitioned from a PTE to PMD here? Looks to me like we should goto a new label right after the 'pmd = pmd_offset(pud, addr);', no?