INFO: task kworker/u8:11:3506 blocked for more than 143 seconds.
Not tainted 6.16.0-rc5-next-20250711-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:11 state:D stack:20808 pid:3506 tgid:3506 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
context_switch kernel/sched/core.c:5314 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6697
__schedule_loop kernel/sched/core.c:6775 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6790
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6847
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1187
__down_write_common kernel/locking/rwsem.c:1319 [inline]
__down_write kernel/locking/rwsem.c:1328 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1593
f2fs_down_write fs/f2fs/f2fs.h:2234 [inline]
f2fs_balance_fs+0x5ab/0x7f0 fs/f2fs/segment.c:464
f2fs_write_inode+0x3fb/0x5f0 fs/f2fs/inode.c:819
write_inode fs/fs-writeback.c:1525 [inline]
__writeback_single_inode+0x6f1/0xff0 fs/fs-writeback.c:1745
writeback_sb_inodes+0x6c7/0x1010 fs/fs-writeback.c:1976
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13c5a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13c5a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13c5a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
4 locks held by kworker/u8:11/3506:
#0: ffff88801fec5948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801fec5948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc9000c387bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc9000c387bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff8880329ea0e0 (&type->s_umount_key#42){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88807bdb1410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline]
#3: ffff88807bdb1410 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x5ab/0x7f0 fs/f2fs/segment.c:464
2 locks held by syslogd/5207:
2 locks held by getty/5615:
#0: ffff88814d8e30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
5 locks held by syz-executor139/5859:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-next-20250711-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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+0xfee/0x1030 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 5859 Comm: syz-executor139 Not tainted 6.16.0-rc5-next-20250711-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__lock_acquire+0x862/0xd20 kernel/locking/lockdep.c:-1
Code: 31 c8 01 d6 29 c2 89 c1 c1 c1 10 31 d1 01 f0 41 89 cf 41 c1 c7 13 29 ce 41 31 f7 01 c1 44 29 f8 44 01 f9 41 c1 c7 04 41 31 c7 <49> c1 e7 20 49 09 cf 83 3d b4 3c 06 0e 00 0f 85 36 02 00 00 48 83
RSP: 0018:ffffc90003f9e388 EFLAGS: 00000082
RAX: 0000000019565a15 RBX: 0000000000000005 RCX: 00000000c1b73c66
RDX: 000000005e8a41e1 RSI: 00000000411edd21 RDI: ffff888025d11e00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff81729ea5
R10: ffffc90003f9e5d8 R11: ffffffff81ac7b20 R12: 0000000029a088d2
R13: ffff888025d128f0 R14: ffff888025d129b8 R15: 000000008211f3f7
FS: 0000555565b2a380(0000) GS:ffff888125bc6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7a3f440700 CR3: 00000000334ce000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4396
kmalloc_noprof include/linux/slab.h:905 [inline]
slab_free_hook mm/slub.c:2369 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x166/0x400 mm/slub.c:4782
f2fs_submit_page_read+0x116/0x190 fs/f2fs/data.c:1113
f2fs_get_read_data_folio+0x4a4/0x7d0 fs/f2fs/data.c:1271
gc_data_segment fs/f2fs/gc.c:1638 [inline]
do_garbage_collect+0x3866/0x64b0 fs/f2fs/gc.c:1823
f2fs_gc+0xc87/0x2590 fs/f2fs/gc.c:1928
f2fs_balance_fs+0x5f7/0x7f0 fs/f2fs/segment.c:466
f2fs_map_blocks+0x3c19/0x4510 fs/f2fs/data.c:1791
f2fs_expand_inode_data+0x5b1/0xa60 fs/f2fs/file.c:1920
f2fs_fallocate+0x4f5/0x990 fs/f2fs/file.c:2023
vfs_fallocate+0x669/0x7e0 fs/open.c:342
ioctl_preallocate fs/ioctl.c:290 [inline]
file_ioctl+0x611/0x780 fs/ioctl.c:-1
do_vfs_ioctl+0xb33/0x1430 fs/ioctl.c:577
__do_sys_ioctl fs/ioctl.c:596 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:584
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: 0033:0x7f6c3245fb99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 17 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe1d56dbb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00002000000000c0 RCX: 00007f6c3245fb99
RDX: 00002000000000c0 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00002000000000e0 R08: 0000555565b2b4c0 R09: 0000555565b2b4c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00002000000000d0
R13: 00002000000000c8 R14: 00002000000000c2 R15: 00007f6c324a803b
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.276 msecs