[ Upstream commit e34c8dd238d0c9368b746480f313055f5bab5040 ]
Following process,
jbd2_journal_commit_transaction
// there are several dirty buffer heads in transaction->t_checkpoint_list
P1 wb_workfn
jbd2_log_do_checkpoint
if (buffer_locked(bh)) // false
__block_write_full_page
trylock_buffer(bh)
test_clear_buffer_dirty(bh)
if (!buffer_dirty(bh))
__jbd2_journal_remove_checkpoint(jh)
if (buffer_write_io_error(bh)) // false
>> bh IO error occurs <<
jbd2_cleanup_journal_tail
__jbd2_update_log_tail
jbd2_write_superblock
// The bh won't be replayed in next mount.
, which could corrupt the ext4 image, fetch a reproducer in [Link].
Since writeback process clears buffer dirty after locking buffer head,
we can fix it by try locking buffer and check dirtiness while buffer is
locked, the buffer head can be removed if it is neither dirty nor locked.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217490
Fixes: 470decc613ab ("[PATCH] jbd2: initial copy of files from jbd")
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-5-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c2d6fd9d6f35079f1669f0100f05b46708c74b7f ]
There is a long-standing metadata corruption issue that happens from
time to time, but it's very difficult to reproduce and analyse, benefit
from the JBD2_CYCLE_RECORD option, we found out that the problem is the
checkpointing process miss to write out some buffers which are raced by
another do_get_write_access(). Looks below for detail.
jbd2_log_do_checkpoint() //transaction X
//buffer A is dirty and not belones to any transaction
__buffer_relink_io() //move it to the IO list
__flush_batch()
write_dirty_buffer()
do_get_write_access()
clear_buffer_dirty
__jbd2_journal_file_buffer()
//add buffer A to a new transaction Y
lock_buffer(bh)
//doesn't write out
__jbd2_journal_remove_checkpoint()
//finish checkpoint except buffer A
//filesystem corrupt if the new transaction Y isn't fully write out.
Due to the t_checkpoint_list walking loop in jbd2_log_do_checkpoint()
have already handles waiting for buffers under IO and re-added new
transaction to complete commit, and it also removing cleaned buffers,
this makes sure the list will eventually get empty. So it's fine to
leave buffers on the t_checkpoint_list while flushing out and completely
stop using the t_checkpoint_io_list.
Cc: stable@vger.kernel.org
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Tested-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230606135928.434610-2-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: e34c8dd238d0 ("jbd2: Fix wrongly judgement for buffer head removing while doing checkpoint")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 214eb5a4d8a2032fb9f0711d1b202eb88ee02920 ]
Now that __jbd2_journal_remove_checkpoint() can detect buffer io error
and mark journal checkpoint error, then we abort the journal later
before updating log tail to ensure the filesystem works consistently.
So we could remove other redundant buffer io error checkes.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-5-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Stable-dep-of: e34c8dd238d0 ("jbd2: Fix wrongly judgement for buffer head removing while doing checkpoint")
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6c02757c936063f0631b4e43fe156f8c8f1f351f ]
There's issue when do io test:
WARN: soft lockup - CPU#45 stuck for 11s! [jbd2/dm-2-8:4170]
CPU: 45 PID: 4170 Comm: jbd2/dm-2-8 Kdump: loaded Tainted: G OE
Call trace:
dump_backtrace+0x0/0x1a0
show_stack+0x24/0x30
dump_stack+0xb0/0x100
watchdog_timer_fn+0x254/0x3f8
__hrtimer_run_queues+0x11c/0x380
hrtimer_interrupt+0xfc/0x2f8
arch_timer_handler_phys+0x38/0x58
handle_percpu_devid_irq+0x90/0x248
generic_handle_irq+0x3c/0x58
__handle_domain_irq+0x68/0xc0
gic_handle_irq+0x90/0x320
el1_irq+0xcc/0x180
queued_spin_lock_slowpath+0x1d8/0x320
jbd2_journal_commit_transaction+0x10f4/0x1c78 [jbd2]
kjournald2+0xec/0x2f0 [jbd2]
kthread+0x134/0x138
ret_from_fork+0x10/0x18
Analyzed informations from vmcore as follows:
(1) There are about 5k+ jbd2_inode in 'commit_transaction->t_inode_list';
(2) Now is processing the 855th jbd2_inode;
(3) JBD2 task has TIF_NEED_RESCHED flag;
(4) There's no pags in address_space around the 855th jbd2_inode;
(5) There are some process is doing drop caches;
(6) Mounted with 'nodioread_nolock' option;
(7) 128 CPUs;
According to informations from vmcore we know 'journal->j_list_lock' spin lock
competition is fierce. So journal_finish_inode_data_buffers() maybe process
slowly. Theoretically, there is scheduling point in the filemap_fdatawait_range_keep_errors().
However, if inode's address_space has no pages which taged with PAGECACHE_TAG_WRITEBACK,
will not call cond_resched(). So may lead to soft lockup.
journal_finish_inode_data_buffers
filemap_fdatawait_range_keep_errors
__filemap_fdatawait_range
while (index <= end)
nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end, PAGECACHE_TAG_WRITEBACK);
if (!nr_pages)
break; --> If 'nr_pages' is equal zero will break, then will not call cond_resched()
for (i = 0; i < nr_pages; i++)
wait_on_page_writeback(page);
cond_resched();
To solve above issue, add scheduling point in the journal_finish_inode_data_buffers();
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20231211112544.3879780-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 85559227211020b270728104c3b89918f7af27ac ]
The write_flags print in the trace of jbd2_write_superblock() is not
real, so move the modification before the trace.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20231129114740.2686201-1-yi.zhang@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 61187fce8600e8ef90e601be84f9d0f3222c1206 upstream.
JBD2 makes sure journal data is fallen on fs device by sync_blockdev(),
however, other process could intercept the EIO information from bdev's
mapping, which leads journal recovering successful even EIO occurs during
data written back to fs device.
We found this problem in our product, iscsi + multipath is chosen for block
device of ext4. Unstable network may trigger kpartx to rescan partitions in
device mapper layer. Detailed process is shown as following:
mount kpartx irq
jbd2_journal_recover
do_one_pass
memcpy(nbh->b_data, obh->b_data) // copy data to fs dev from journal
mark_buffer_dirty // mark bh dirty
vfs_read
generic_file_read_iter // dio
filemap_write_and_wait_range
__filemap_fdatawrite_range
do_writepages
block_write_full_folio
submit_bh_wbc
>> EIO occurs in disk <<
end_buffer_async_write
mark_buffer_write_io_error
mapping_set_error
set_bit(AS_EIO, &mapping->flags) // set!
filemap_check_errors
test_and_clear_bit(AS_EIO, &mapping->flags) // clear!
err2 = sync_blockdev
filemap_write_and_wait
filemap_check_errors
test_and_clear_bit(AS_EIO, &mapping->flags) // false
err2 = 0
Filesystem is mounted successfully even data from journal is failed written
into disk, and ext4/ocfs2 could become corrupted.
Fix it by comparing the wb_err state in fs block device before recovering
and after recovering.
A reproducer can be found in the kernel bugzilla referenced below.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217888
Cc: stable@vger.kernel.org
Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230919012525.1783108-1-chengzhihao1@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
