From mboxrd@z Thu Jan 1 00:00:00 1970 From: Theodore Ts'o Subject: Re: [PATCH 1/1] jbd2: fix incorrect unlock on j_list_lock Date: Wed, 12 Oct 2016 23:21:13 -0400 Message-ID: <20161013032112.iy4hohrqplsajtye@thunk.org> References: <1426644518-29680-1-git-send-email-tsgatesv@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Taesoo Kim , Ext4 Developers List , LKML , taesoo@gatech.edu, changwoo@gatech.edu, sanidhya@gatech.edu, blee@gatech.edu, csong84@gatech.edu, stable@vger.kernel.org, "Faccini, Bruno" To: Andreas Dilger Return-path: Received: from imap.thunk.org ([74.207.234.97]:56262 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933767AbcJMDXQ (ORCPT ); Wed, 12 Oct 2016 23:23:16 -0400 Content-Disposition: inline In-Reply-To: Sender: linux-ext4-owner@vger.kernel.org List-ID: On Wed, Oct 12, 2016 at 04:58:35PM -0600, Andreas Dilger wrote: > On Mar 17, 2015, at 8:08 PM, Taesoo Kim wrote: > > > > When 'jh->b_transaction == transaction' (asserted by below) > > > > J_ASSERT_JH(jh, (jh->b_transaction == transaction || ... > > > > 'journal->j_list_lock' will be incorrectly unlocked, since > > spin_lock() is called only in the 'if' and 'else-if' blocks but > > not in the missing 'else' case, which results in a hang or an oops.... > > > > Signed-off-by: Taesoo Kim > > We've hit this repeatedly on kernels with commit v3.14-rc2-30-g6e4862a > "jbd2: minimize region locked by j_list_lock in journal_get_create_access" > under heavy load and this patch has fixed the problem. > > It should also be considered for stable kernels after 3.14. > > [I've updated the above commit message slightly to give more details.] > > Reviewed-by: Andreas Dilger Thanks, applied. Apologies, this got lost which is why I hadn't handled it earlier. - Ted