INFO: task syz.0.19:6728 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.19 state:D stack:27976 pid:6728 tgid:6723 ppid:6561 task_flags:0x400040 flags:0x00004004
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]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
__rwbase_read_lock+0xbc/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1466 [inline]
down_read+0x127/0x1f0 kernel/locking/rwsem.c:1539
inode_lock_shared include/linux/fs.h:885 [inline]
f2fs_seek_block fs/f2fs/file.c:458 [inline]
f2fs_llseek+0x1e5/0x1840 fs/f2fs/file.c:545
vfs_llseek fs/read_write.c:389 [inline]
ksys_lseek fs/read_write.c:402 [inline]
__do_sys_lseek fs/read_write.c:412 [inline]
__se_sys_lseek fs/read_write.c:410 [inline]
__x64_sys_lseek+0x155/0x1f0 fs/read_write.c:410
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: 0033:0x7fa1891aebe9
RSP: 002b:00007fa1887f5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000008
RAX: ffffffffffffffda RBX: 00007fa1893d6090 RCX: 00007fa1891aebe9
RDX: 0000000000000004 RSI: 0000000000000008 RDI: 0000000000000004
RBP: 00007fa189231e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa1893d6128 R14: 00007fa1893d6090 R15: 00007fff33b07ba8
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
#0: ffff88801cefc138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801cefc138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90000127bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90000127bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffff8880247ee408 (&wb->work_lock){+.+.}-{3:3}, at: spin_lock_irq include/linux/spinlock_rt.h:93 [inline]
#2: ffff8880247ee408 (&wb->work_lock){+.+.}-{3:3}, at: get_next_work_item fs/fs-writeback.c:2206 [inline]
#2: ffff8880247ee408 (&wb->work_lock){+.+.}-{3:3}, at: wb_do_writeback fs/fs-writeback.c:2301 [inline]
#2: ffff8880247ee408 (&wb->work_lock){+.+.}-{3:3}, at: wb_workfn+0x23c/0xf00 fs/fs-writeback.c:2343
4 locks held by pr/legacy/17:
3 locks held by kworker/1:0/31:
#0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888019898538 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90000a5fbc0 ((work_completion)(&sbi->s_error_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90000a5fbc0 ((work_completion)(&sbi->s_error_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffff888031060078 (&sbi->sb_lock){++++}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline]
#2: ffff888031060078 (&sbi->sb_lock){++++}-{4:4}, at: f2fs_record_stop_reason fs/f2fs/super.c:4418 [inline]
#2: ffff888031060078 (&sbi->sb_lock){++++}-{4:4}, at: f2fs_record_error_work+0x59/0x1c0 fs/f2fs/super.c:4570
1 lock held by khungtaskd/38:
#0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
4 locks held by kworker/u8:6/161:
#0: ffff88801cefc138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801cefc138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90003a3fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90003a3fbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffff888038c6c0d0 (&type->s_umount_key#54){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88805488d990 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2234 [inline]
#3: ffff88805488d990 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x5af/0x7f0 fs/f2fs/segment.c:464
2 locks held by getty/5591:
#0: ffff88823bf3a8a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222
8 locks held by syz.0.19/6724:
2 locks held by syz.0.19/6728:
#0: ffff888032ff5d28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x253/0x320 fs/file.c:1232
#1: ffff888041a56078 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:885 [inline]
#1: ffff888041a56078 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: f2fs_seek_block fs/f2fs/file.c:458 [inline]
#1: ffff888041a56078 (&sb->s_type->i_mutex_key#20){++++}-{4:4}, at: f2fs_llseek+0x1e5/0x1840 fs/f2fs/file.c:545
5 locks held by syz-executor/6737:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 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+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: 6724 Comm: syz.0.19 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+0x15/0xb0 kernel/rcu/tree.c:751
Code: 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 53 65 ff 05 70 08 51 10 e8 1b d3 51 09 <89> c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 10
RSP: 0018:ffffc900049763d8 EFLAGS: 00000282
RAX: 0000000000000000 RBX: ffffffff8af669ba RCX: 3364b7b8133a7100
RDX: 0000000000000000 RSI: ffffffff8b620fe0 RDI: ffffffff8b620fa0
RBP: dffffc0000000000 R08: 0000000000000000 R09: ffffffff8172b165
R10: ffffc90004976518 R11: ffffffff81aae2f0 R12: 1ffff9200092ec99
R13: ffffc90004976500 R14: ffffc900049764c8 R15: ffffffff8172b165
FS: 00007fa1888166c0(0000) GS:ffff8881268bf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6a629ecd58 CR3: 000000003b28c000 CR4: 00000000003526f0
Call Trace:
rcu_read_lock include/linux/rcupdate.h:842 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xd4/0x2390 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+0x3e/0x60 mm/kasan/common.c:47
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548
slab_free_hook mm/slub.c:2383 [inline]
slab_free mm/slub.c:4695 [inline]
kmem_cache_free+0x3ef/0x510 mm/slub.c:4797
f2fs_read_end_io+0x398/0x9d0 fs/f2fs/data.c:-1
f2fs_submit_page_read+0x116/0x190 fs/f2fs/data.c:1110
f2fs_get_read_data_folio+0x4a4/0x7d0 fs/f2fs/data.c:1268
f2fs_get_lock_data_folio+0x54/0x1f0 fs/f2fs/data.c:1319
move_data_page fs/f2fs/gc.c:1460 [inline]
gc_data_segment fs/f2fs/gc.c:1684 [inline]
do_garbage_collect+0x3061/0x6410 fs/f2fs/gc.c:1826
f2fs_gc+0xca9/0x2580 fs/f2fs/gc.c:1931
f2fs_balance_fs+0x5fb/0x7f0 fs/f2fs/segment.c:466
f2fs_map_blocks+0x345f/0x4130 fs/f2fs/data.c:1792
f2fs_expand_inode_data+0x5b1/0xa60 fs/f2fs/file.c:1923
f2fs_fallocate+0x4f8/0x990 fs/f2fs/file.c:2026
vfs_fallocate+0x672/0x7f0 fs/open.c:342
ioctl_preallocate fs/ioctl.c:290 [inline]
file_ioctl+0x61d/0x780 fs/ioctl.c:-1
do_vfs_ioctl+0xb36/0x1440 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: 0033:0x7fa1891aebe9
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:00007fa188816038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa1893d5fa0 RCX: 00007fa1891aebe9
RDX: 00002000000000c0 RSI: 0000000040305828 RDI: 0000000000000004
RBP: 00007fa189231e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa1893d6038 R14: 00007fa1893d5fa0 R15: 00007fff33b07ba8