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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 410A1C2BA2B for ; Tue, 14 Apr 2020 02:59:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 261E12072D for ; Tue, 14 Apr 2020 02:59:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404338AbgDNC7S (ORCPT ); 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