From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mout.gmx.net ([212.227.15.19]:44913 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725768AbeH3FID (ORCPT ); Thu, 30 Aug 2018 01:08:03 -0400 Subject: Re: [PATCH 3/6] btrfs-progs: Don't report dirty leaked eb using BUG_ON To: Nikolay Borisov , Qu Wenruo , linux-btrfs@vger.kernel.org References: <20180803055022.9816-1-wqu@suse.com> <20180803055022.9816-4-wqu@suse.com> From: Qu Wenruo Message-ID: <42d18735-a32f-143c-f9fc-16a4363cfc42@gmx.com> Date: Thu, 30 Aug 2018 09:08:18 +0800 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On 2018/8/29 下午10:52, Nikolay Borisov wrote: > > > On 3.08.2018 08:50, Qu Wenruo wrote: >> Another BUG_ON() during fuzz/003: >> ------ >> ====== RUN MAYFAIL /home/adam/btrfs/btrfs-progs/btrfs check --init-csum-tree /home/adam/btrfs/btrfs-progs/tests//fuzz-tests/images/bko-161821.raw.restored >> [1/7] checking root items >> Fixed 0 roots. >> [2/7] checking extents >> parent transid verify failed on 4198400 wanted 14 found 1114126 >> parent transid verify failed on 4198400 wanted 14 found 1114126 >> Ignoring transid failure >> owner ref check failed [4198400 4096] >> repair deleting extent record: key [4198400,169,0] >> adding new tree backref on start 4198400 len 4096 parent 0 root 5 >> Repaired extent references for 4198400 >> ref mismatch on [4222976 4096] extent item 1, found 0 >> backref 4222976 root 7 not referenced back 0x5617f8ecf780 >> incorrect global backref count on 4222976 found 1 wanted 0 >> backpointer mismatch on [4222976 4096] >> owner ref check failed [4222976 4096] >> repair deleting extent record: key [4222976,169,0] >> Repaired extent references for 4222976 >> [3/7] checking free space cache >> [4/7] checking fs roots >> parent transid verify failed on 4198400 wanted 14 found 1114126 >> Ignoring transid failure >> Wrong generation of child node/leaf, wanted: 1114126, have: 14 >> root 5 missing its root dir, recreating >> parent transid verify failed on 4198400 wanted 14 found 1114126 >> Ignoring transid failure >> ERROR: child eb corrupted: parent bytenr=4222976 item=0 parent level=1 child level=2 >> ERROR: errors found in fs roots >> extent buffer leak: start 4222976 len 4096 >> extent_io.c:611: free_extent_buffer_internal: BUG_ON `eb->flags & EXTENT_DIRTY` triggered, value 1 >> failed (ignored, ret=134): /home/adam/btrfs/btrfs-progs/btrfs check --init-csum-tree /home/adam/btrfs/btrfs-progs/tests//fuzz-tests/images/bko-161821.raw.restored >> mayfail: returned code 134 (SIGABRT), not ignored >> test failed for case 003-multi-check-unmounted >> ------ >> >> Since we're shifting to using btrfs_abort_transaction() in btrfs-progs, >> it will be more and more common to see dirty leaked eb. >> Instead of BUG_ON(), we only needs to report it as warning. > > > So how are such leaked extents supposed to be cleaned? So when > transaction_aborted is set we just return some errors from various > functions but I don't see how modified extents in the transaction are freed? They're freed by extent_io_tree_cleanup(), called by the following call trace: close_ctree_fs_info() |- btrfs_cleanup_all_caches() |- extent_io_tree_cleanup(&fs_info->extent_cache) |- free_extent_buffer_nocache() And inside extent_io_tree_cleanup(), it's also where we do leaked extent buffer detection. Thanks, Qu >> >> Signed-off-by: Qu Wenruo >> --- >> extent_io.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/extent_io.c b/extent_io.c >> index 198492699438..b8510b0ae94e 100644 >> --- a/extent_io.c >> +++ b/extent_io.c >> @@ -608,7 +608,11 @@ static void free_extent_buffer_internal(struct extent_buffer *eb, bool free_now) >> eb->refs--; >> BUG_ON(eb->refs < 0); >> if (eb->refs == 0) { >> - BUG_ON(eb->flags & EXTENT_DIRTY); >> + if (eb->flags & EXTENT_DIRTY) { >> + warning( >> + "dirty eb leak (aborted trans): start %llu len %u", >> + eb->start, eb->len); >> + } >> list_del_init(&eb->recow); >> if (eb->flags & EXTENT_BUFFER_DUMMY || free_now) >> free_extent_buffer_final(eb); >>