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INFO: task hung in __generic_file_fsync (4)

Status: auto-obsoleted due to no activity on 2024/12/15 09:38
Subsystems: bcachefs exfat ext4
[Documentation on labels]
First crash: 269d, last: 112d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-4.19 INFO: task hung in __generic_file_fsync ext4 C 211 675d 1109d 0/1 upstream: reported C repro on 2021/12/25 03:26
android-49 INFO: task hung in __generic_file_fsync 1 1951d 1951d 0/3 auto-closed as invalid on 2020/01/02 10:29
upstream INFO: task hung in __generic_file_fsync (5) fs C inconclusive 8 2d03h 3d21h 0/28 upstream: reported C repro on 2025/01/03 06:09
upstream INFO: task hung in __generic_file_fsync (3) exfat ntfs3 C inconclusive done 8 373d 880d 25/28 fixed on 2024/02/21 18:23
upstream INFO: task hung in __generic_file_fsync (2) fs mm C done done 28 1831d 1832d 15/28 fixed on 2020/02/18 10:28

Sample crash report:
INFO: task syz.1.182:6844 blocked for more than 143 seconds.
      Not tainted 6.11.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.182       state:D stack:27360 pid:6844  tgid:6818  ppid:6300   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6621
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678
 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
 __down_write_common kernel/locking/rwsem.c:1306 [inline]
 __down_write kernel/locking/rwsem.c:1315 [inline]
 down_write+0x1d7/0x220 kernel/locking/rwsem.c:1580
 inode_lock include/linux/fs.h:800 [inline]
 __generic_file_fsync+0x9a/0x190 fs/libfs.c:1533
 generic_file_fsync+0x73/0xf0 fs/libfs.c:1570
 vfs_fsync_range fs/sync.c:188 [inline]
 vfs_fsync fs/sync.c:202 [inline]
 do_fsync fs/sync.c:212 [inline]
 __do_sys_fsync fs/sync.c:220 [inline]
 __se_sys_fsync fs/sync.c:218 [inline]
 __x64_sys_fsync+0x19a/0x1e0 fs/sync.c:218
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff8a8b7def9
RSP: 002b:00007ff8a85de038 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
RAX: ffffffffffffffda RBX: 00007ff8a8d36058 RCX: 00007ff8a8b7def9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007ff8a8bf0b76 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ff8a8d36058 R15: 00007fffcab1dea8
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/u8:0/11:
1 lock held by khungtaskd/30:
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e738320 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6626
2 locks held by kworker/u8:4/63:
 #0: ffff8880b893e998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:560
 #1: ffff8880b8928948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x441/0x770 kernel/sched/psi.c:989
3 locks held by kworker/u8:5/83:
 #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88801a889148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc9000232fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc9000232fd00 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:276
3 locks held by kworker/u8:6/1069:
 #0: ffff88802f8c6948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3206 [inline]
 #0: ffff88802f8c6948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x90a/0x1830 kernel/workqueue.c:3312
 #1: ffffc90004037d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3207 [inline]
 #1: ffffc90004037d00 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x945/0x1830 kernel/workqueue.c:3312
 #2: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd0/0x16f0 net/ipv6/addrconf.c:4194
1 lock held by dhcpcd/4888:
 #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2ce/0x1bc0 net/ipv4/devinet.c:1101
2 locks held by getty/4977:
 #0: ffff88803013f0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6ac/0x1e00 drivers/tty/n_tty.c:2211
1 lock held by syz.1.182/6820:
1 lock held by syz.1.182/6844:
 #0: ffff888059a78180 (&type->i_mutex_dir_key#25){++++}-{3:3}, at: inode_lock include/linux/fs.h:800 [inline]
 #0: ffff888059a78180 (&type->i_mutex_dir_key#25){++++}-{3:3}, at: __generic_file_fsync+0x9a/0x190 fs/libfs.c:1533
1 lock held by syz-executor/8128:
 #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644
1 lock held by syz-executor/8367:
 #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644
7 locks held by syz-executor/8438:
 #0: ffff88802fe16420 (sb_writers#8){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2882 [inline]
 #0: ffff88802fe16420 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x227/0xc90 fs/read_write.c:586
 #1: ffff888020729888 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1eb/0x500 fs/kernfs/file.c:325
 #2: ffff8880283484b8 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x20f/0x500 fs/kernfs/file.c:326
 #3: ffffffff8f314108 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xfc/0x480 drivers/net/netdevsim/bus.c:216
 #4: ffff88805fe1a0e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline]
 #4: ffff88805fe1a0e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline]
 #4: ffff88805fe1a0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xce/0x7c0 drivers/base/dd.c:1292
 #5: ffff88805fe1b250 (&devlink->lock_key#19){+.+.}-{3:3}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1672
 #6: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: unregister_netdevice_notifier_net+0x89/0x3a0 net/core/dev.c:1915
1 lock held by syz-executor/8491:
 #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
 #0: ffffffff8fa79e08 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x6e6/0xcf0 net/core/rtnetlink.c:6644
2 locks held by syz.1.390/8569:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xff4/0x1040 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 3010 Comm: kworker/u8:8 Not tainted 6.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: bat_events batadv_nc_worker
RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline]
RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline]
RIP: 0010:rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:124 [inline]
RIP: 0010:rcu_is_watching+0x5a/0xb0 kernel/rcu/tree.c:726
Code: f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 3c ed 7d 00 48 c7 c3 78 7c 03 00 49 03 1e 48 89 d8 48 c1 e8 03 42 0f b6 04 38 <84> c0 75 22 8b 03 65 ff 0d d1 13 8a 7e 74 10 83 e0 04 c1 e8 02 5b
RSP: 0018:ffffc90009a27a00 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: ffff8880b8937c78 RCX: ffffffff816ff390
RDX: 0000000000000000 RSI: ffffffff8c3fbaa0 RDI: ffffffff8c3fba60
RBP: ffffc90009a27b48 R08: ffffffff8ff74a2f R09: 1ffffffff1fee945
R10: dffffc0000000000 R11: fffffbfff1fee946 R12: 1ffff92001344f50
R13: ffffffff8b7b500b R14: ffffffff8e08aa58 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f86fb1ff000 CR3: 000000000e534000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 trace_lock_release include/trace/events/lock.h:69 [inline]
 lock_release+0xbf/0xa30 kernel/locking/lockdep.c:5770
 rcu_lock_release include/linux/rcupdate.h:336 [inline]
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
 batadv_nc_worker+0x28b/0x610 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
 worker_thread+0x870/0xd30 kernel/workqueue.c:3393
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/16 09:36 upstream 98f7e32f20d2 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __generic_file_fsync
2024/09/13 21:18 upstream 196145c606d0 b58f933c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __generic_file_fsync
2024/09/08 14:36 upstream d1f2d51b711a 9750182a .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __generic_file_fsync
2024/08/19 18:11 upstream 47ac09b91bef 9f0ab3fb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __generic_file_fsync
2024/07/07 06:34 upstream 22f902dfc51e 2a40360c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs INFO: task hung in __generic_file_fsync
2024/04/14 04:32 linux-next 9ed46da14b9b c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root INFO: task hung in __generic_file_fsync
2024/04/13 00:22 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci b5d2afe8745b c8349e48 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 INFO: task hung in __generic_file_fsync
* Struck through repros no longer work on HEAD.