INFO: task syz.0.313:8261 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.313 state:D stack:24456 pid:8261 tgid:8260 ppid:5847 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
f2fs_issue_checkpoint+0x376/0x570 fs/f2fs/checkpoint.c:-1
f2fs_do_sync_file+0x86c/0x1860 fs/f2fs/file.c:346
generic_write_sync include/linux/fs.h:3043 [inline]
f2fs_file_write_iter+0x752/0x2400 fs/f2fs/file.c:5259
do_iter_readv_writev+0x62b/0x8d0 fs/read_write.c:-1
vfs_writev+0x323/0x970 fs/read_write.c:1057
do_pwritev fs/read_write.c:1153 [inline]
__do_sys_pwritev2 fs/read_write.c:1211 [inline]
__se_sys_pwritev2+0x17c/0x2a0 fs/read_write.c:1202
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f62a117eba9
RSP: 002b:00007f629f3e6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 00007f62a13c5fa0 RCX: 00007f62a117eba9
RDX: 0000000000000001 RSI: 00002000000001c0 RDI: 0000000000000005
RBP: 00007f62a1201e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000e7b R11: 0000000000000246 R12: 0000000000000000
R13: 00007f62a13c6038 R14: 00007f62a13c5fa0 R15: 00007ffd37742ee8
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:3/57:
#0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801a6f4138 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000123fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000123fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8ecc6700 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:658
#3: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12719
3 locks held by kworker/u8:6/765:
#0: ffff8881404ba138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff8881404ba138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc900040d7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900040d7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffff8880359ea0d0 (&type->s_umount_key#59){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
2 locks held by dhcpcd/5498:
#0: ffffffff8ecb7ad8 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5f1/0x790 net/socket.c:1321
#1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:577
2 locks held by getty/5595:
#0: ffff888033c9d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222
3 locks held by kworker/u8:11/6640:
1 lock held by syz.0.313/8261:
#0: ffff8880359ea488 (sb_writers#19){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline]
#0: ffff8880359ea488 (sb_writers#19){.+.+}-{0:0}, at: vfs_writev+0x28e/0x970 fs/read_write.c:1055
3 locks held by f2fs_ckpt-7:0/8266:
1 lock held by syz-executor/8848:
#0: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: inet6_rtm_newaddr+0x5b7/0xd20 net/ipv6/addrconf.c:5027
7 locks held by syz-executor/8904:
#0: ffff888034cda488 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline]
#0: ffff888034cda488 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682
#1: ffff88805a471478 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
#2: ffff8880271562d8 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880271562d8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
#3: ffffffff8e542d38 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:234
#4: ffff88801a3850d8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#4: ffff88801a3850d8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1096 [inline]
#4: ffff88801a3850d8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800 drivers/base/dd.c:1294
#5: ffff88801a386300 (&devlink->lock_key#13){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160 drivers/net/netdevsim/dev.c:1721
#6: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xe5/0x670 drivers/net/netdevsim/netdev.c:1135
4 locks held by syz-executor/8907:
#0: ffff888034cda488 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3108 [inline]
#0: ffff888034cda488 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682
#1: ffff88805a471878 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1df/0x540 fs/kernfs/file.c:343
#2: ffff8880271562d8 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline]
#2: ffff8880271562d8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x232/0x540 fs/kernfs/file.c:344
#3: ffffffff8e542d38 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360 drivers/net/netdevsim/bus.c:234
2 locks held by syz.2.368/9031:
#0: ffff8880359ea0d0 (&type->s_umount_key#59){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff8880359ea0d0 (&type->s_umount_key#59){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1: ffff888142ff0870 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888142ff0870 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19b/0xa50 fs/fs-writeback.c:2832
2 locks held by syz-executor/9037:
#0: ffffffff8f1d79e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f1d79e8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8f1d79e8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8ecd35f8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8266 Comm: f2fs_ckpt-7:0 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
RIP: 0010:rcu_is_watching+0x2e/0xb0 kernel/rcu/tree.c:751
Code: 41 57 41 56 53 65 ff 05 70 28 51 10 e8 1b f3 51 09 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 10 2d 25 8d <4c> 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 dc 90 78 00
RSP: 0018:ffffc90003e476f8 EFLAGS: 00000097
RAX: 0000000000000001 RBX: 0000000000000001 RCX: 803bdefcac667d00
RDX: 0000000000000001 RSI: ffffffff8b6215e0 RDI: ffffffff8b6215a0
RBP: ffffc90003e47800 R08: ffff8880327a44af R09: 1ffff110064f4895
R10: dffffc0000000000 R11: ffffed10064f4896 R12: dffffc0000000000
R13: ffffffff8af8a270 R14: ffffffff8d252d18 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8881269bc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fad0724246c CR3: 00000000380fc000 CR4: 00000000003526f0
Call Trace:
trace_lock_release include/trace/events/lock.h:69 [inline]
lock_release+0x4b/0x3e0 kernel/locking/lockdep.c:5879
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:149 [inline]
_raw_spin_unlock_irqrestore+0x70/0x110 kernel/locking/spinlock.c:194
rt_mutex_slowtrylock kernel/locking/rtmutex.c:1395 [inline]
rt_mutex_try_acquire kernel/locking/rtmutex.c:320 [inline]
__rt_mutex_lock kernel/locking/rtmutex.c:1812 [inline]
rwbase_write_lock+0x140/0x750 kernel/locking/rwbase_rt.c:244
f2fs_down_write fs/f2fs/f2fs.h:2234 [inline]
block_operations fs/f2fs/checkpoint.c:1258 [inline]
f2fs_write_checkpoint+0x98b/0x1df0 fs/f2fs/checkpoint.c:1638
__write_checkpoint_sync fs/f2fs/checkpoint.c:1756 [inline]
__checkpoint_and_complete_reqs+0xd9/0x3b0 fs/f2fs/checkpoint.c:1775
issue_checkpoint_thread+0xd9/0x260 fs/f2fs/checkpoint.c:1806
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245