From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp1040.oracle.com ([156.151.31.81]:48395 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751061AbcINST4 (ORCPT ); Wed, 14 Sep 2016 14:19:56 -0400 Date: Wed, 14 Sep 2016 11:19:04 -0700 From: Liu Bo To: Josef Bacik Cc: Chris Mason , linux-btrfs@vger.kernel.org, David Sterba Subject: Re: [PATCH] Btrfs: kill BUG_ON in do_relocation Message-ID: <20160914181904.GB32358@localhost.localdomain> Reply-To: bo.li.liu@oracle.com References: <1473870467-18721-1-git-send-email-bo.li.liu@oracle.com> <9426999a-06a8-d169-753a-0c4df5c7c4f8@fb.com> <793b8de8-e612-d075-8764-0ef59963cf4a@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Wed, Sep 14, 2016 at 01:31:31PM -0400, Josef Bacik wrote: > On 09/14/2016 01:29 PM, Chris Mason wrote: > > > > > > On 09/14/2016 01:13 PM, Josef Bacik wrote: > > > On 09/14/2016 12:27 PM, Liu Bo wrote: > > > > While updating btree, we try to push items between sibling > > > > nodes/leaves in order to keep height as low as possible. > > > > But we don't memset the original places with zero when > > > > pushing items so that we could end up leaving stale content > > > > in nodes/leaves. One may read the above stale content by > > > > increasing btree blocks' @nritems. > > > > > > > > > > Ok this sounds really bad. Is this as bad as I think it sounds? We > > > should probably fix this like right now right? > > > > He's bumping @nritems with a fuzzer I think? As in this happens when someone > > forces it (or via some other bug) but not in normal operations. > > > > Oh ok if this happens with a fuzzer than this is fine, but I'd rather do > -EIO so we know this is something bad with the fs. -EIO may be more appropriate to be given while reading btree blocks and checking their validation? > And change the changelog > to make it explicit that this is the result of fs corruption, not normal > operation. Then you can add > > Reviewed-by: Josef Bacik OK, make sense. Thanks, -liubo