Received: by 2002:a25:6193:0:0:0:0:0 with SMTP id v141csp4417713ybb; Tue, 14 Apr 2020 06:59:09 -0700 (PDT) X-Google-Smtp-Source: APiQypJOLrDr6udlIBgTLWkEZXml9NAUngI5S31qzkVsoGNYu5gFy/nl024wpoZZjHCwUoTcyc+7 X-Received: by 2002:a05:6402:14c8:: with SMTP id f8mr8774672edx.272.1586872749398; Tue, 14 Apr 2020 06:59:09 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1586872749; cv=none; d=google.com; s=arc-20160816; b=prZzqyBZtXVDs2xjrzKkxLJ0dh3lRZp0qHwCamfc3w2oVexHmmNllj6S/FbDHnbJop 0o42NnsaZ58PimSS/g0qobKxv27dPdNQ2Rug1zWmncTdo02RiONv9vH9Qd+j7fE87hFG UJfrMW3w4dMv6LKQ5+5PSIJnm6NucNc5osN/prOVarCBcoRul1gLvciWSJrlgOBCDSOb TWRDHvpmbAUhtJWh7QniVhSFdx/uZ2DuHLOO2BOS0/50/6OXqTOWYQo2Hl8lqh6VUf22 TusFQshsKjve4NwtG4CiCdLJx4oaLbgpszti3UF2ibXj8jMW9LaKCJ/vtyoCvAsKXDD9 sE2A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:in-reply-to:content-disposition :mime-version:references:message-id:subject:to:from:date; bh=Wgk9lIf2Qu3RVStMO9F8DT5FO3XTndh9iVmYwv9pX0c=; b=rYM2OMBJU6/2Gu4rZF5W/qT3bcJCazeoda87jStncRe41JsWKFNWnGyfiWg6Kk47wL 53g7u5hGDvSROryr9k+vZtCVKAuJIvxQOVO0gE7/vRrt4IBeVfqCY4N9utEpFmi68hw1 iZbFMs0xfp4MLimBZl834ES/RGdRTwkOcSrIqCGM0gEb/agX1E5K2sc/XeXRBXynncdf 8fnuevNK44wEN5s4pFDoaDolq3ueKg57DTLJh11EI66SmUn/6Y+E7Hn+PHmM5u76ubQ/ o5aySZrGp1TcKd9zqb8lPDmUUMg8uGoCTL709aQkAkyFRvWnvGcbc3UPgsLoOoHyWneJ whjQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-ext4-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-ext4-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id u18si8777103edq.152.2020.04.14.06.58.41; Tue, 14 Apr 2020 06:59:09 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-ext4-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-ext4-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-ext4-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404337AbgDNC7S (ORCPT + 99 others); Mon, 13 Apr 2020 22:59:18 -0400 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:50475 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2404336AbgDNC7S (ORCPT ); Mon, 13 Apr 2020 22:59:18 -0400 Received: from callcc.thunk.org (pool-72-93-95-157.bstnma.fios.verizon.net [72.93.95.157]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 03E2xFuh014642 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 13 Apr 2020 22:59:15 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id D5EEA42013D; Mon, 13 Apr 2020 22:59:14 -0400 (EDT) Date: Mon, 13 Apr 2020 22:59:14 -0400 From: "Theodore Y. Ts'o" To: Ext4 Developers List Subject: Re: [PATCH] ext4: fix BUG_ON in fs/ext4/page_io.c:ext4_release_io_end() Message-ID: <20200414025914.GE90651@mit.edu> References: <20200414022842.272657-1-tytso@mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200414022842.272657-1-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Mon, Apr 13, 2020 at 10:28:42PM -0400, Theodore Ts'o wrote: > The function ext4_release_io_end() can be called by > ext4_put_io_end_defer() with the EXT4_IO_UNWRITTEN flag set and > io_end->size is 0. In that case, it's safe to release the io_end > structure, since if io_end->size is zero, there is no unwritten region > to release. > > This can be reproduced using generic/300, although not very reliably, > and almost never using a freshly rebooted kernel. > > Google-Bug-Id: 15054006 > Signed-off-by: "Theodore Ts'o" NACK; this patch no longer applies given the move to use iomap for direct I/O. - Ted