From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from bombadil.infradead.org ([198.137.202.133]:41350 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751795AbeEFTC4 (ORCPT ); Sun, 6 May 2018 15:02:56 -0400 Date: Sun, 6 May 2018 12:02:56 -0700 From: Matthew Wilcox To: Jeff Layton Cc: stable@vger.kernel.org Subject: Re: [v4.14.y PATCH] errseq: Always report a writeback error once Message-ID: <20180506190256.GB13604@bombadil.infradead.org> References: <20180506155957.25163-1-jlayton@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180506155957.25163-1-jlayton@kernel.org> Sender: stable-owner@vger.kernel.org List-ID: On Sun, May 06, 2018 at 11:59:57AM -0400, Jeff Layton wrote: > From: Matthew Wilcox > > The errseq_t infrastructure assumes that errors which occurred before > the file descriptor was opened are of no interest to the application. > This turns out to be a regression for some applications, notably Postgres. > > Before errseq_t, a writeback error would be reported exactly once (as > long as the inode remained in memory), so Postgres could open a file, > call fsync() and find out whether there had been a writeback error on > that file from another process. > > This patch changes the errseq infrastructure to report errors to all > file descriptors which are opened after the error occurred, but before > it was reported to any file descriptor. This restores the user-visible > behaviour. > > [ jlayton: fix up conflicts in comments ] Thanks! I was just getting to this conflict :-) I agree this resolution is the best one for 4.14.x