From: Ye Bin yebin10@huawei.com
[ Upstream commit b98535d091795a79336f520b0708457aacf55c67 ]
We got issue as follows: ------------[ cut here ]------------ kernel BUG at fs/jbd2/transaction.c:389! invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 9 PID: 131 Comm: kworker/9:1 Not tainted 5.17.0-862.14.0.6.x86_64-00001-g23f87daf7d74-dirty #197 Workqueue: events flush_stashed_error_work RIP: 0010:start_this_handle+0x41c/0x1160 RSP: 0018:ffff888106b47c20 EFLAGS: 00010202 RAX: ffffed10251b8400 RBX: ffff888128dc204c RCX: ffffffffb52972ac RDX: 0000000000000200 RSI: 0000000000000004 RDI: ffff888128dc2050 RBP: 0000000000000039 R08: 0000000000000001 R09: ffffed10251b840a R10: ffff888128dc204f R11: ffffed10251b8409 R12: ffff888116d78000 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff888128dc2000 FS: 0000000000000000(0000) GS:ffff88839d680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001620068 CR3: 0000000376c0e000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> jbd2__journal_start+0x38a/0x790 jbd2_journal_start+0x19/0x20 flush_stashed_error_work+0x110/0x2b3 process_one_work+0x688/0x1080 worker_thread+0x8b/0xc50 kthread+0x26f/0x310 ret_from_fork+0x22/0x30 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]---
Above issue may happen as follows: umount read procfs error_work ext4_put_super flush_work(&sbi->s_error_work);
ext4_mb_seq_groups_show ext4_mb_load_buddy_gfp ext4_mb_init_group ext4_mb_init_cache ext4_read_block_bitmap_nowait ext4_validate_block_bitmap ext4_error ext4_handle_error schedule_work(&EXT4_SB(sb)->s_error_work);
ext4_unregister_sysfs(sb); jbd2_journal_destroy(sbi->s_journal); journal_kill_thread journal->j_flags |= JBD2_UNMOUNT;
flush_stashed_error_work jbd2_journal_start start_this_handle BUG_ON(journal->j_flags & JBD2_UNMOUNT);
To solve this issue, we call 'ext4_unregister_sysfs() before flushing s_error_work in ext4_put_super().
Signed-off-by: Ye Bin yebin10@huawei.com Reviewed-by: Jan Kara jack@suse.cz Reviewed-by: Ritesh Harjani riteshh@linux.ibm.com Link: https://lore.kernel.org/r/20220322012419.725457-1-yebin10@huawei.com Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ext4/super.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 5e6c03458317..3e26edeca8c7 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1176,18 +1176,23 @@ static void ext4_put_super(struct super_block *sb) int aborted = 0; int i, err;
- ext4_unregister_li_request(sb); - ext4_quota_off_umount(sb); - - destroy_workqueue(sbi->rsv_conversion_wq); - /* * Unregister sysfs before destroying jbd2 journal. * Since we could still access attr_journal_task attribute via sysfs * path which could have sbi->s_journal->j_task as NULL + * Unregister sysfs before flush sbi->s_error_work. + * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If + * read metadata verify failed then will queue error work. + * flush_stashed_error_work will call start_this_handle may trigger + * BUG_ON. */ ext4_unregister_sysfs(sb);
+ ext4_unregister_li_request(sb); + ext4_quota_off_umount(sb); + + destroy_workqueue(sbi->rsv_conversion_wq); + if (sbi->s_journal) { aborted = is_journal_aborted(sbi->s_journal); err = jbd2_journal_destroy(sbi->s_journal);