syzbot


INFO: task hung in f2fs_destroy_xattr_caches

Status: auto-obsoleted due to no activity on 2025/09/10 12:12
Subsystems: f2fs
[Documentation on labels]
First crash: 164d, last: 120d

Sample crash report:
INFO: task syz.2.57:6850 blocked for more than 144 seconds.
      Not tainted 6.16.0-rc1-syzkaller-g19272b37aa4f #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.57        state:D stack:0     pid:6850  tgid:6850  ppid:6490   task_flags:0x40044c flags:0x00000019
Call trace:
 __switch_to+0x414/0x834 arch/arm64/kernel/process.c:735 (T)
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x1414/0x2a28 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6878
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6935
 __mutex_lock_common+0xbd0/0x2190 kernel/locking/mutex.c:679
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799
 kmem_cache_destroy+0x58/0x178 mm/slab_common.c:511
 f2fs_destroy_xattr_caches+0x44/0x54 fs/f2fs/xattr.c:853
 f2fs_put_super+0x98c/0xeec fs/f2fs/super.c:1712
 generic_shutdown_super+0x12c/0x2b8 fs/super.c:643
 kill_block_super+0x44/0x90 fs/super.c:1753
 kill_f2fs_super+0x2b8/0x584 fs/f2fs/super.c:5082
 deactivate_locked_super+0xc4/0x12c fs/super.c:474
 deactivate_super+0xe0/0x100 fs/super.c:507
 cleanup_mnt+0x31c/0x3ac fs/namespace.c:1417
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1424
 task_work_run+0x1dc/0x260 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x51c/0x19fc kernel/exit.c:955
 do_group_exit+0x194/0x22c kernel/exit.c:1104
 get_signal+0x11dc/0x12f8 kernel/signal.c:3034
 do_signal+0x274/0x4438 arch/arm64/kernel/signal.c:1615
 do_notify_resume+0xac/0x1ec arch/arm64/kernel/entry-common.c:148
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline]
 el0_svc+0xb4/0x17c arch/arm64/kernel/entry-common.c:768
 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
INFO: task syz.4.148:7164 blocked for more than 144 seconds.
      Not tainted 6.16.0-rc1-syzkaller-g19272b37aa4f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.148       state:D stack:0     pid:7164  tgid:7163  ppid:6493   task_flags:0x400140 flags:0x00000019
Call trace:
 __switch_to+0x414/0x834 arch/arm64/kernel/process.c:735 (T)
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x1414/0x2a28 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6878
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6935
 __mutex_lock_common+0xbd0/0x2190 kernel/locking/mutex.c:679
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799
 bio_find_or_create_slab block/bio.c:122 [inline]
 bioset_init+0x1d0/0x654 block/bio.c:1799
 bch2_fs_ec_init+0x30/0x40 fs/bcachefs/ec.c:2366
 bch2_fs_alloc fs/bcachefs/super.c:1012 [inline]
 bch2_fs_open+0x1ca4/0x1fa4 fs/bcachefs/super.c:2404
 bch2_fs_get_tree+0x360/0xfd0 fs/bcachefs/fs.c:2473
 vfs_get_tree+0x90/0x28c fs/super.c:1802
 do_new_mount+0x228/0x814 fs/namespace.c:3885
 path_mount+0x5b4/0xde0 fs/namespace.c:4209
 do_mount fs/namespace.c:4222 [inline]
 __do_sys_mount fs/namespace.c:4433 [inline]
 __se_sys_mount fs/namespace.c:4410 [inline]
 __arm64_sys_mount+0x3e8/0x468 fs/namespace.c:4410
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767
 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

Showing all locks held in the system:
1 lock held by init/1:
6 locks held by kworker/R-netns/8:
 #0: ffff0000c18a2148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff8000978f7ba0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
 #2: ffff80009275bcd0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf4/0x6c0 net/core/net_namespace.c:662
 #3: ffff0000cc9950e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
 #3: ffff0000cc9950e8 (&dev->mutex){....}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:108 [inline]
 #3: ffff0000cc9950e8 (&dev->mutex){....}-{4:4}, at: devlink_pernet_pre_exit+0xe4/0x380 net/devlink/core.c:506
 #4: ffff0000cc996250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devl_lock net/devlink/core.c:276 [inline]
 #4: ffff0000cc996250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devl_dev_lock net/devlink/devl_internal.h:109 [inline]
 #4: ffff0000cc996250 (&devlink->lock_key#3){+.+.}-{4:4}, at: devlink_pernet_pre_exit+0xf0/0x380 net/devlink/core.c:506
 #5: ffff80008f74f880 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x58/0x528 kernel/rcu/tree.c:3782
2 locks held by kworker/u8:0/12:
3 locks held by kworker/u8:1/13:
2 locks held by kworker/1:1/26:
1 lock held by khungtaskd/32:
 #0: ffff80008f749e40 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
3 locks held by kworker/u8:2/41:
2 locks held by pr/ttyAMA0/43:
2 locks held by kworker/u8:5/238:
4 locks held by kworker/u8:6/381:
2 locks held by kworker/u8:7/1596:
3 locks held by kworker/u8:8/4367:
2 locks held by kworker/u8:10/4536:
1 lock held by klogd/6092:
2 locks held by udevd/6103:
2 locks held by dhcpcd/6157:
3 locks held by dhcpcd/6158:
1 lock held by crond/6232:
2 locks held by getty/6255:
 #0: ffff0000d2c150a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009b8db2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222
3 locks held by syz-executor/6487:
3 locks held by syz-executor/6488:
 #0: ffff80008fe71288 (bio_slab_lock){+.+.}-{4:4}, at: bio_put_slab block/bio.c:140 [inline]
 #0: ffff80008fe71288 (bio_slab_lock){+.+.}-{4:4}, at: bioset_exit+0x1f8/0x3dc block/bio.c:1758
 #1: ffff80008f5e2e10 (cpu_hotplug_lock){++++}-{0:0}, at: kmem_cache_destroy+0x48/0x178 mm/slab_common.c:510
 #2: ffff80008f827c78 (slab_mutex){+.+.}-{4:4}, at: kmem_cache_destroy+0x58/0x178 mm/slab_common.c:511
3 locks held by syz.2.57/6850:
 #0: ffff0000d2f760e0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff0000d2f760e0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff0000d2f760e0 (&type->s_umount_key#58){++++}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506
 #1: ffff80008f5e2e10 (cpu_hotplug_lock){++++}-{0:0}, at: kmem_cache_destroy+0x48/0x178 mm/slab_common.c:510
 #2: ffff80008f827c78 (slab_mutex){+.+.}-{4:4}, at: kmem_cache_destroy+0x58/0x178 mm/slab_common.c:511
1 lock held by syz.4.148/7164:
 #0: ffff80008fe71288 (bio_slab_lock){+.+.}-{4:4}, at: bio_find_or_create_slab block/bio.c:122 [inline]
 #0: ffff80008fe71288 (bio_slab_lock){+.+.}-{4:4}, at: bioset_init+0x1d0/0x654 block/bio.c:1799
2 locks held by syz-executor/7228:
3 locks held by kworker/u8:12/7231:
3 locks held by kworker/u8:13/7232:
2 locks held by syz-executor/7233:

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


Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/06/12 12:06 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 19272b37aa4f 98683f8f .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in f2fs_destroy_xattr_caches
2025/05/23 00:48 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci d7fa1af5b33e 0919b50b .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in f2fs_destroy_xattr_caches
2025/04/29 09:00 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 66d2d510fea3 aeb6ec69 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in f2fs_destroy_xattr_caches
* Struck through repros no longer work on HEAD.