INFO: task kworker/u4:2:154 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:2 state:D stack:24424 pid: 154 ppid: 2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:1)
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11bb/0x4390 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
rwsem_down_write_slowpath+0xc46/0x11f0 kernel/locking/rwsem.c:1165
f2fs_balance_fs+0x47d/0x660 fs/f2fs/segment.c:528
f2fs_write_inode+0x531/0x760 fs/f2fs/inode.c:745
write_inode fs/fs-writeback.c:1505 [inline]
__writeback_single_inode+0x6c3/0xda0 fs/fs-writeback.c:1715
writeback_sb_inodes+0x9fe/0x1610 fs/fs-writeback.c:1940
__writeback_inodes_wb+0x12a/0x3f0 fs/fs-writeback.c:2011
wb_writeback+0x455/0xb90 fs/fs-writeback.c:2116
wb_check_background_flush fs/fs-writeback.c:2182 [inline]
wb_do_writeback fs/fs-writeback.c:2270 [inline]
wb_workfn+0xb47/0xe60 fs/fs-writeback.c:2298
process_one_work+0x863/0x1000 kernel/workqueue.c:2310
worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Showing all locks held in the system:
2 locks held by kworker/u4:0/9:
#0: ffff888016879138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90000ce7d00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
3 locks held by kworker/1:0/21:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90000db7d00 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff88801a3e6240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x271/0x3240 drivers/net/netdevsim/fib.c:1480
2 locks held by kworker/1:1/23:
1 lock held by khungtaskd/27:
#0: ffffffff8c11c720 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
6 locks held by kworker/u4:1/144:
4 locks held by kworker/u4:2/154:
#0: ffff88801958d138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90002007d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff88807b2500e0 (&type->s_umount_key#50){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:418
#3: ffff8880740351b0 (&sbi->gc_lock){+.+.}-{3:3}, at: f2fs_balance_fs+0x47d/0x660 fs/f2fs/segment.c:528
2 locks held by getty/3945:
#0: ffff88802b927098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
2 locks held by kworker/1:4/4235:
#0: ffff888016872138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000317fd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
3 locks held by kworker/1:5/4245:
#0: ffff888016870938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc9000321fd00 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff8880548bf400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_trap_report_work+0x56/0xb40 drivers/net/netdevsim/dev.c:757
2 locks held by kworker/u4:7/4332:
3 locks held by kworker/0:16/4424:
3 locks held by kworker/0:21/4431:
5 locks held by syz.1.70/4640:
3 locks held by kworker/1:9/4723:
#0: ffff888016a35d38 ((wq_completion)pm){+.+.}-{0:0}, at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1
#1: ffffc90004247d00 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285
#2: ffff8881482c7220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#2: ffff8881482c7220 (&dev->mutex){....}-{3:3}, at: usb_remote_wakeup+0x1f/0xf0 drivers/usb/core/hub.c:3802
1 lock held by udevd/5041:
1 lock held by udevd/5077:
4 locks held by syz-executor/5159:
#0: ffff88807f74c460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
#1: ffff888060e49c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#2: ffff888147c02e88 (kn->active#297){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x208/0x4c0 fs/kernfs/file.c:288
#3: ffffffff8cb72308 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x13c/0x740 drivers/net/netdevsim/bus.c:295
7 locks held by syz-executor/5163:
#0: ffff88807f74c460 (sb_writers#8){.+.+}-{0:0}, at: vfs_write+0x28a/0xd00 fs/read_write.c:590
#1: ffff88806194cc88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e5/0x4c0 fs/kernfs/file.c:287
#2: ffff888147c04008 (kn->active#296){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x208/0x4c0 fs/kernfs/file.c:288
#3: ffffffff8cb72308 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xce/0x380 drivers/net/netdevsim/bus.c:344
#4: ffff888148783178 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:764 [inline]
#4: ffff888148783178 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1044 [inline]
#4: ffff888148783178 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xb0/0x750 drivers/base/dd.c:1259
#5: ffff8880548bf400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1359 [inline]
#5: ffff8880548bf400 (&nsim_dev->port_list_lock){+.+.}-{3:3}, at: nsim_dev_reload_destroy+0x115/0x240 drivers/net/netdevsim/dev.c:1561
#6: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: netdev_wait_allrefs net/core/dev.c:10567 [inline]
#6: ffffffff8d238748 (rtnl_mutex){+.+.}-{3:3}, at: netdev_run_todo+0x53f/0xa40 net/core/dev.c:10681
3 locks held by syz.5.148/5332:
1 lock held by syz.5.148/5335:
1 lock held by rm/5336:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4640 Comm: syz.1.70 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:kasan_check_range+0x1aa/0x290 mm/kasan/generic.c:-1
Code: d9 4d 89 d6 4d 8d 56 07 4d 85 f6 4d 0f 49 d6 49 83 e2 f8 4d 29 d6 74 12 41 80 39 00 0f 85 a0 00 00 00 49 ff c1 49 ff ce 75 ee <5b> 41 5e 41 5f c3 84 db 75 61 f7 c3 00 ff 00 00 75 5e f7 c3 00 00
RSP: 0018:ffffc900042264a0 EFLAGS: 00000056
RAX: 0000000000000101 RBX: 0000000000000000 RCX: ffffffff815cafa4
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbd1d0
RBP: 0000000000000006 R08: dffffc0000000000 R09: fffffbfff1ff7a3b
R10: fffffbfff1ff7a3b R11: 1ffffffff1ff7a3a R12: 0000000000000040
R13: dffffc0000000000 R14: 0000000000000001 R15: dffffc0000000001
FS: 00007f841ff926c0(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa415ed76c0 CR3: 000000007e8ab000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
instrument_atomic_read include/linux/instrumented.h:71 [inline]
test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
hlock_class kernel/locking/lockdep.c:197 [inline]
mark_lock+0x94/0x320 kernel/locking/lockdep.c:4569
mark_held_locks kernel/locking/lockdep.c:4193 [inline]
__trace_hardirqs_on_caller kernel/locking/lockdep.c:4219 [inline]
lockdep_hardirqs_on_prepare+0x365/0x760 kernel/locking/lockdep.c:4278
trace_hardirqs_on+0x67/0x80 kernel/trace/trace_preemptirq.c:49
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
_raw_spin_unlock_irqrestore+0x82/0x100 kernel/locking/spinlock.c:194
__debug_check_no_obj_freed lib/debugobjects.c:982 [inline]
debug_check_no_obj_freed+0x515/0x530 lib/debugobjects.c:1003
slab_free_hook mm/slub.c:1685 [inline]
slab_free_freelist_hook+0x8b/0x170 mm/slub.c:1736
slab_free mm/slub.c:3504 [inline]
kmem_cache_free+0x8f/0x210 mm/slub.c:3520
submit_bio_checks+0x310/0x18f0 block/blk-core.c:899
__submit_bio+0x59e/0x810 block/blk-core.c:911
__submit_bio_noacct_mq block/blk-core.c:997 [inline]
submit_bio_noacct+0x5f1/0x6d0 block/blk-core.c:1027
submit_bio+0x2be/0x560 block/blk-core.c:1089
f2fs_submit_page_read+0x239/0x2b0 fs/f2fs/data.c:1050
f2fs_get_read_data_page+0x390/0x560 fs/f2fs/data.c:1224
gc_data_segment fs/f2fs/gc.c:1504 [inline]
do_garbage_collect+0x3dfb/0x60a0 fs/f2fs/gc.c:1671
f2fs_gc+0x8a9/0x1900 fs/f2fs/gc.c:1765
f2fs_balance_fs+0x491/0x660 fs/f2fs/segment.c:529
f2fs_map_blocks+0x1962/0x3310 fs/f2fs/data.c:1700
expand_inode_data+0x4a0/0x6e0 fs/f2fs/file.c:1716
f2fs_fallocate+0x423/0x8c0 fs/f2fs/file.c:1818
vfs_fallocate+0x587/0x6f0 fs/open.c:308
ioctl_preallocate fs/ioctl.c:294 [inline]
file_ioctl fs/ioctl.c:-1 [inline]
do_vfs_ioctl+0x1b70/0x1de0 fs/ioctl.c:853
__do_sys_ioctl fs/ioctl.c:872 [inline]
__se_sys_ioctl+0x83/0x170 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8421d6cfc9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f841ff92038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8421fc4180 RCX: 00007f8421d6cfc9
RDX: 00002000000000c0 RSI: 0000000040305828 RDI: 0000000000000005
RBP: 00007f8421deff91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8421fc4218 R14: 00007f8421fc4180 R15: 00007fff74149f38