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=-6.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 2F9E1C433DF for ; Mon, 19 Oct 2020 15:05:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C17952231B for ; Mon, 19 Oct 2020 15:05:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="gjNRMhzR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729849AbgJSPFo (ORCPT ); Mon, 19 Oct 2020 11:05:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729562AbgJSPFo (ORCPT ); Mon, 19 Oct 2020 11:05:44 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6562EC0613CE; Mon, 19 Oct 2020 08:05:44 -0700 (PDT) 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=bFSiuYqB4gwYvv/iZyzJmlqTMgfw3DQ04mxWA+a4zz8=; b=gjNRMhzR4NWeuUkCP2OuEJTVHP fewl680n7c4HRDiiRMpp52VauoWDCZK80TaMfhH3kq6fMTh6SsN1XFNJXGJkvTBWhxdlXr5xEktjK pvpY5JNh8agErSuEeuptPQ6S/S621map4Ma8WPf4k6G+gQQ0pBHMwP1NgqhwAcbzm7rA29VmKYqpv lj0LhIontRqUDXzxL1gizjcITxaXKxOp5UtTGGLzpN5fBQmI8GoffXSqbwZFkKFqLl5UMztbYWyxJ Yxt08S9WnVFD1LxhZoPusN0CGuHRfkNnGo8P2zaQpV7OuJ76O58TxpNR9OJNeKtxb2p3FCKyg1ldZ jFPgpmdg==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kUWjB-00080A-Is; Mon, 19 Oct 2020 15:05:38 +0000 Date: Mon, 19 Oct 2020 16:05:37 +0100 From: Matthew Wilcox To: David Howells Cc: torvalds@linux-foundation.org, Takashi Iwai , dwysocha@redhat.com, linux-afs@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] cachefiles: Drop superfluous readpages aops NULL check Message-ID: <20201019150537.GS20115@casper.infradead.org> References: <160311941493.2265023.9116264838885193100.stgit@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <160311941493.2265023.9116264838885193100.stgit@warthog.procyon.org.uk> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 19, 2020 at 03:56:54PM +0100, David Howells wrote: > From: Takashi Iwai > > After the recent actions to convert readpages aops to readahead, the > NULL checks of readpages aops in cachefiles_read_or_alloc_page() may > hit falsely. More badly, it's an ASSERT() call, and this panics. > > Drop the superfluous NULL checks for fixing this regression. > > [DH: Note that cachefiles never actually used readpages, so this check was > never actually necessary] > > BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=208883 > BugLink: https://bugzilla.opensuse.org/show_bug.cgi?id=1175245 > Fixes: 9ae326a69004 ("CacheFiles: A cache that backs onto a mounted filesystem") > Signed-off-by: Takashi Iwai > Signed-off-by: David Howells > cc: Matthew Wilcox (Oracle) Acked-by: Matthew Wilcox (Oracle)