syzbot


INFO: task hung in f2fs_balance_fs

Status: auto-obsoleted due to no activity on 2023/03/18 03:56
Reported-by: syzbot+400da1030cd5825f95f1@syzkaller.appspotmail.com
First crash: 550d, last: 524d
Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in f2fs_balance_fs f2fs C 199 415d 555d 0/1 upstream: reported C repro on 2022/10/18 13:55
linux-6.1 INFO: task hung in f2fs_balance_fs (2) 2 149d 171d 0/3 auto-obsoleted due to no activity on 2024/03/06 18:04
linux-6.1 INFO: task hung in f2fs_balance_fs (3) 15 14h44m 29d 0/3 upstream: reported on 2024/03/27 06:53
upstream INFO: task hung in f2fs_balance_fs f2fs C done inconclusive 363 9h50m 407d 0/26 upstream: reported C repro on 2023/03/15 03:28
linux-6.1 INFO: task hung in f2fs_balance_fs 20 351d 414d 0/3 auto-obsoleted due to no activity on 2023/08/22 15:19
linux-5.15 INFO: task hung in f2fs_balance_fs origin:upstream C 44 14h51m 414d 0/3 upstream: reported C repro on 2023/03/08 13:34

Sample crash report:
F2FS-fs (loop5): inconsistent node block, nid:6, node_footer[nid:0,ino:0,ofs:0,cpver:0,blkaddr:0]
F2FS-fs (loop5): inconsistent node block, nid:6, node_footer[nid:0,ino:0,ofs:0,cpver:0,blkaddr:0]
F2FS-fs (loop5): inconsistent node block, nid:6, node_footer[nid:0,ino:0,ofs:0,cpver:0,blkaddr:0]
INFO: task kworker/u4:4:2850 blocked for more than 140 seconds.
      Not tainted 4.14.299-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/u4:4    D27240  2850      2 0x80000000
Workqueue: writeback wb_workfn (flush-7:5)
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 f2fs_balance_fs+0x412/0x5a0 fs/f2fs/segment.c:435
 f2fs_write_inode+0x182/0x1d0 fs/f2fs/inode.c:524
 write_inode fs/fs-writeback.c:1241 [inline]
 __writeback_single_inode+0x6a4/0x1010 fs/fs-writeback.c:1439
 writeback_sb_inodes+0x48b/0xd30 fs/fs-writeback.c:1645
 __writeback_inodes_wb+0xbf/0x230 fs/fs-writeback.c:1716
 wb_writeback+0x710/0xb80 fs/fs-writeback.c:1822
 wb_check_old_data_flush fs/fs-writeback.c:1935 [inline]
 wb_do_writeback fs/fs-writeback.c:1959 [inline]
 wb_workfn+0x708/0xf50 fs/fs-writeback.c:1988
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406
INFO: task syz-executor.3:9549 blocked for more than 140 seconds.
      Not tainted 4.14.299-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D29984  9549   8010 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 wb_wait_for_completion fs/fs-writeback.c:222 [inline]
 wb_wait_for_completion+0x118/0x170 fs/fs-writeback.c:218
 sync_inodes_sb+0x173/0x880 fs/fs-writeback.c:2447
 sync_inodes_one_sb+0x3d/0x50 fs/sync.c:74
 iterate_supers+0x124/0x490 fs/super.c:613
 sys_sync+0x78/0x130 fs/sync.c:113
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x5e/0xd3

Showing all locks held in the system:
1 lock held by khungtaskd/1533:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8702a1b9>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
4 locks held by kworker/u4:4/2850:
 #0:  ("writeback"){+.+.}, at: [<ffffffff81365eb0>] process_one_work+0x6b0/0x14a0 kernel/workqueue.c:2088
 #1:  ((&(&wb->dwork)->work)){+.+.}, at: [<ffffffff81365ee6>] process_one_work+0x6e6/0x14a0 kernel/workqueue.c:2092
 #2:  (&type->s_umount_key#67){++++}, at: [<ffffffff8187b0bb>] trylock_super+0x1b/0xe0 fs/super.c:402
 #3:  (&sbi->gc_mutex){+.+.}, at: [<ffffffff82ccb5b2>] f2fs_balance_fs+0x412/0x5a0 fs/f2fs/segment.c:435
2 locks held by syz-executor.3/9549:
 #0:  (&type->s_umount_key#67){++++}, at: [<ffffffff8187b25a>] iterate_supers+0xda/0x490 fs/super.c:611
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline]
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] sync_inodes_sb+0x156/0x880 fs/fs-writeback.c:2445
2 locks held by syz-executor.0/9994:
 #0:  (&type->s_umount_key#67){++++}, at: [<ffffffff8187b25a>] iterate_supers+0xda/0x490 fs/super.c:611
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline]
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] sync_inodes_sb+0x156/0x880 fs/fs-writeback.c:2445
2 locks held by syz-executor.3/10257:
 #0:  (&type->s_umount_key#67){++++}, at: [<ffffffff8187b25a>] iterate_supers+0xda/0x490 fs/super.c:611
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline]
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] sync_inodes_sb+0x156/0x880 fs/fs-writeback.c:2445
2 locks held by syz-executor.0/10795:
 #0:  (&type->s_umount_key#67){++++}, at: [<ffffffff8187b25a>] iterate_supers+0xda/0x490 fs/super.c:611
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline]
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] sync_inodes_sb+0x156/0x880 fs/fs-writeback.c:2445
2 locks held by syz-executor.3/10800:
 #0:  (&type->s_umount_key#67){++++}, at: [<ffffffff8187b25a>] iterate_supers+0xda/0x490 fs/super.c:611
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:338 [inline]
 #1:  (&bdi->wb_switch_rwsem){+.+.}, at: [<ffffffff8190ee16>] sync_inodes_sb+0x156/0x880 fs/fs-writeback.c:2445

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1533 Comm: khungtaskd Not tainted 4.14.299-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 309 Comm: kworker/u4:3 Not tainted 4.14.299-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: bat_events batadv_nc_worker
task: ffff8880b4ede080 task.stack: ffff8880b4ee8000
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__lock_release kernel/locking/lockdep.c:3739 [inline]
RIP: 0010:lock_release+0x18b/0x870 kernel/locking/lockdep.c:4017
RSP: 0018:ffff8880b4eefc48 EFLAGS: 00000006
RAX: 0000000000000003 RBX: 1ffff110169ddf8c RCX: 1ffffffff127a6c4
RDX: 0000000000000004 RSI: 0000000000000002 RDI: ffff8880b4ede904
RBP: ffffffff88f78600 R08: 0000000000000000 R09: 0000000000020011
R10: 0000000000000000 R11: ffff8880b4ede080 R12: ffffffff86ebf1d0
R13: ffff8880b4ede080 R14: ffff88813fe468c0 R15: ffff8880a4e25800
FS:  0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f330004b028 CR3: 00000000a17fe000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rcu_lock_release include/linux/rcupdate.h:247 [inline]
 rcu_read_unlock include/linux/rcupdate.h:685 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:422 [inline]
 batadv_nc_worker+0x5a7/0xc50 net/batman-adv/network-coding.c:728
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2117
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2251
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:406
Code: 59 c7 08 0f 82 2a 04 00 00 48 c7 c0 20 36 3d 89 48 ba 00 00 00 00 00 fc ff df 48 89 c1 83 e0 07 48 c1 e9 03 83 c0 03 0f b6 14 11 <65> 4c 8b 34 25 c0 7f 02 00 38 d0 7c 08 84 d2 0f 85 c8 05 00 00 

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/18 03:56 linux-4.14.y e911713e40ca 5bb70014 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-4-14 INFO: task hung in f2fs_balance_fs
2022/10/23 07:13 linux-4.14.y 9d5c0b3a8e1a c0b80a55 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 INFO: task hung in f2fs_balance_fs
2022/10/22 15:19 linux-4.14.y 9d5c0b3a8e1a c0b80a55 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 INFO: task hung in f2fs_balance_fs
* Struck through repros no longer work on HEAD.