From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp2120.oracle.com ([156.151.31.85]:37370 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753506AbeEURzX (ORCPT ); Mon, 21 May 2018 13:55:23 -0400 Date: Mon, 21 May 2018 10:54:57 -0700 From: "Darrick J. Wong" To: Matthew Wilcox Cc: Jeff Layton , "Theodore Y. Ts'o" , linux-fsdevel@vger.kernel.org, fstests@vger.kernel.org, xfs Subject: Re: [PATCH] fs: clear writeback errors in inode_init_always Message-ID: <20180521175457.GI23858@magnolia> References: <20180518225037.GA26206@thunk.org> <630faadb74f608aa5a42649b81657e8b62d46bc3.camel@kernel.org> <20180519152700.GB4507@magnolia> <20180519153619.GA24698@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180519153619.GA24698@bombadil.infradead.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Sat, May 19, 2018 at 08:36:19AM -0700, Matthew Wilcox wrote: > On Sat, May 19, 2018 at 08:27:00AM -0700, Darrick J. Wong wrote: > > From: Darrick J. Wong > > > > In inode_init_always(), we clear the inode mapping flags, which clears > > any retained error (AS_EIO, AS_ENOSC) bits. Unfortunately, we do not > > typo of ENOSPC in case you do a new version Fixed, thanks. > > also clear wb_err, which means that old mapping errors can leak through > > to new inodes. > > > > This is crucial for the XFS inode allocation path because we recycle old > > in-core inodes and we do not want error state from an old file to leak > > into the new file. This bug was discovered by running generic/036 and > > generic/047 in a loop and noticing that the EIOs generated by the > > collision of direct and buffered writes in generic/036 would survive the > > remount between 036 and 047, and get reported to the fsyncs (on > > different files on a reformatted fs!) in generic/047. > > > > Since we're changing the semantics of inode_init_always, we must also > > change xfs_reinit_inode to retain the writeback error state when we go > > to recover an inode that has been torn down in the vfs but not yet > > disposed of by XFS. > > Don't you also need to preserve inode->i_mapping->flags across the > reinitialisation for the users which aren't yet using ->wb_err? At first I thought (mistakenly) that xfs had been completely converted, but digging further we still use the old filemap_check_errors. It seems reasonable to me that if we're going to resurrect an incore inode then we should try to hang on to AS_EIO/AS_ENOSPC for as long as we can. --D > > +++ b/fs/xfs/xfs_icache.c > > @@ -298,6 +298,7 @@ xfs_reinit_inode( > > uint64_t version = inode_peek_iversion(inode); > > umode_t mode = inode->i_mode; > > dev_t dev = inode->i_rdev; > > + errseq_t old_err = inode->i_mapping->wb_err; > > > > error = inode_init_always(mp->m_super, inode); > > > > @@ -306,6 +307,7 @@ xfs_reinit_inode( > > inode_set_iversion_queried(inode, version); > > inode->i_mode = mode; > > inode->i_rdev = dev; > > + inode->i_mapping->wb_err = old_err; > > return error; > > } > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html