From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from imap.thunk.org ([74.207.234.97]:47842 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752173AbeERWul (ORCPT ); Fri, 18 May 2018 18:50:41 -0400 Date: Fri, 18 May 2018 18:50:37 -0400 From: "Theodore Y. Ts'o" To: Matthew Wilcox Cc: linux-fsdevel@vger.kernel.org, fstests@vger.kernel.org Subject: commit b4678df184b causing xfstests regressions Message-ID: <20180518225037.GA26206@thunk.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Hi Matthew, Commit b4678df184b: "errseq: Always report a writeback error once" appears to be causing xfstests regressions. For ext4, running "gce-xfstests -c 4k -g auto" will result in reliable shared/298 failures which go away if I revert b4678df184b. Darrick has also reported occasional generic/047 failures, which I have seen at least once as well. I believe two are linked, because after instrumenting mke2fs in shared/298, the failure is happening after creating a new 300 MB file: dd if=/dev/zero of=$img_file bs=1M count=300 &> /dev/null creating a new loop device loop_dev=$(_create_loop_device $img_file) ... and then run mke2fs on that loop device. The instrumentation of mke2fs shows that the first fsync() on /dev/loop0 (in lib/ext2fs/closefs.c) which is failing with EIO. I haven't had a chance to really drill down on it, but I think what is going on is there is some former test which exercises an error path (using dm_error, or some such), and somehow the errseq_t for the loop device isn't getting reset, or the inode for the underlying backing file, had an unitialized errseq_t. Can you take a closer look at this? Thanks, - Ted