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 98DA2C19F28 for ; Wed, 27 Jul 2022 13:29:28 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C1512940019; Wed, 27 Jul 2022 09:29:27 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B9EC2940012; Wed, 27 Jul 2022 09:29:27 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A3E8B940019; Wed, 27 Jul 2022 09:29:27 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 8FD15940012 for ; Wed, 27 Jul 2022 09:29:27 -0400 (EDT) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 66A5D12023C for ; Wed, 27 Jul 2022 13:29:27 +0000 (UTC) X-FDA: 79732961574.02.8EF2107 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf31.hostedemail.com (Postfix) with ESMTP id 92D42200A0 for ; Wed, 27 Jul 2022 13:29:25 +0000 (UTC) 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=HT2rOBSyTRGmZLXB5THzZMPG0tRMQrdvo4co8YN86Jw=; b=mgg+6ctM5v5lYiiaaOooVV00Cu M7JHlQPx6inDqn92HaduWdqp41FWaYU1S8zVRaZI8LKIYzIV5O+dudfbqJ+FIbxJebWx2zw2MNxKY 3dGeKs8WZTU23WWFVdmqukjz2MsU7IEA8arARlu+eXEKMEVmAbEq5GThfLkfYrBEA3a/MJU+XV/pE Qa/Tk4KikIq9E5jB/ovphAxTOEtzPIGgQdrlI7v0jInqK5FXJjZ0BxyhO0eQaMWRaDlLrMxhNqj1A 9dZfcwuXJ5328CaV4cUNJ+orL+PVRuEFCWcOGvQYr9VTwA93a71kHWF+KJ+v8IUaPqAhFR4OCu0Jb CF2iOc8w==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1oGh69-002wOq-Ig; Wed, 27 Jul 2022 13:29:13 +0000 Date: Wed, 27 Jul 2022 14:29:13 +0100 From: Matthew Wilcox To: Yongqiang Liu Cc: dhowells@redhat.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, zhangxiaoxu5@huawei.com, yanaijie@huawei.com, vbabka@suse.cz, wangkefeng.wang@huawei.com Subject: Re: [PATCH] mm/folio-compact: fix potential NULL pointer in pagecache_get_page Message-ID: References: <20220727064621.534528-1-liuyongqiang13@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220727064621.534528-1-liuyongqiang13@huawei.com> ARC-Authentication-Results: i=1; imf31.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=mgg+6ctM; spf=none (imf31.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=1658928566; a=rsa-sha256; cv=none; b=Jaw0a7enDA611mbgdFkxzs6Jen5UwJW/9Jtl/AXSJtkhrJT3M/S3vuJJRFcUYxy0OzylHE 8TIKNGgdxY3lxL2dgIZ69u2Ptt34hIwejU/PfeOy6Lzl7un/5u3nHd71Uew4b6WVkW2KNB A6sWSILiZ7nDADYY3mm3xSkODgl0Isk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1658928566; 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=HT2rOBSyTRGmZLXB5THzZMPG0tRMQrdvo4co8YN86Jw=; b=QoYp3nmenG1MPoedB2ujKx7SAxQ87+1Yo9aQGGu7XWk3xPC6VCUELQ80GbZkmliusFVqLM v2d/4Q0i2bwXaQT+E5NsRcHga2BNJi32tyr1w0GkDdIhc5r9yO64bXFOJZ+BJwezhsnFLf sb6gw+hRd5m8BwtoR861MgrpI4oAgmI= X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 92D42200A0 Authentication-Results: imf31.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=mgg+6ctM; spf=none (imf31.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Stat-Signature: ifpbt4dkhpqji5qk5uafsfa8tafzacfx X-Rspam-User: X-HE-Tag: 1658928565-394384 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Jul 27, 2022 at 06:46:21AM +0000, Yongqiang Liu wrote: > When __filemap_get_folio() failed and returned NULL, we would > get a NULL pointer dereference in pagecache_get_page. No we wouldn't.