INFO: task syz.4.288:8416 blocked for more than 143 seconds.
Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.288 state:D stack:28952 pid:8416 tgid:8347 ppid:5825 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
io_schedule+0x81/0xe0 kernel/sched/core.c:7742
folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317
folio_wait_writeback+0xb0/0x100 mm/page-writeback.c:3149
__filemap_fdatawait_range+0x147/0x230 mm/filemap.c:539
filemap_fdatawait_keep_errors+0x31/0xd0 mm/filemap.c:633
wait_sb_inodes fs/fs-writeback.c:2714 [inline]
sync_inodes_sb+0x7a9/0xa10 fs/fs-writeback.c:2836
sync_filesystem+0x17a/0x230 fs/sync.c:64
__do_sys_syncfs fs/sync.c:160 [inline]
__se_sys_syncfs+0x94/0x110 fs/sync.c:149
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8f5138e969
RSP: 002b:00007f8f5226e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000132
RAX: ffffffffffffffda RBX: 00007f8f515b6080 RCX: 00007f8f5138e969
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007f8f51410ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f8f515b6080 R15: 00007ffd9f131d78
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
2 locks held by getty/5582:
#0: ffff88803483a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900033332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/1:7/5909:
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90004467c60 (key_gc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90004467c60 (key_gc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#2: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz.4.288/8349:
#0: ffff8880564ba420 (sb_writers#30){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
#0: ffff8880564ba420 (sb_writers#30){.+.+}-{0:0}, at: vfs_writev+0x274/0x9a0 fs/read_write.c:1053
2 locks held by syz.4.288/8416:
#0: ffff8880564ba0e0 (&type->s_umount_key#85){++++}-{4:4}, at: __do_sys_syncfs fs/sync.c:159 [inline]
#0: ffff8880564ba0e0 (&type->s_umount_key#85){++++}-{4:4}, at: __se_sys_syncfs+0x8c/0x110 fs/sync.c:149
#1: ffff8880564ba948 (&s->s_sync_lock){+.+.}-{4:4}, at: wait_sb_inodes fs/fs-writeback.c:2653 [inline]
#1: ffff8880564ba948 (&s->s_sync_lock){+.+.}-{4:4}, at: sync_inodes_sb+0x255/0xa10 fs/fs-writeback.c:2836
2 locks held by bch-copygc/loop/8408:
2 locks held by syz.1.437/9742:
#0: ffff8880564ba0e0 (&type->s_umount_key#85){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880564ba0e0 (&type->s_umount_key#85){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120
#1: ffff8880564ba948 (&s->s_sync_lock){+.+.}-{4:4}, at: wait_sb_inodes fs/fs-writeback.c:2653 [inline]
#1: ffff8880564ba948 (&s->s_sync_lock){+.+.}-{4:4}, at: sync_inodes_sb+0x255/0xa10 fs/fs-writeback.c:2836
2 locks held by syz.1.437/9743:
#0: ffff8880564ba0e0 (&type->s_umount_key#85){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880564ba0e0 (&type->s_umount_key#85){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120
#1: ffff8880564ba948 (&s->s_sync_lock){+.+.}-{4:4}, at: wait_sb_inodes fs/fs-writeback.c:2653 [inline]
#1: ffff8880564ba948 (&s->s_sync_lock){+.+.}-{4:4}, at: sync_inodes_sb+0x255/0xa10 fs/fs-writeback.c:2836
4 locks held by syz.3.594/11116:
1 lock held by syz.3.594/11153:
1 lock held by dhcpcd-run-hook/11157:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
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: 11156 Comm: syz.6.597 Not tainted 6.15.0-rc5-syzkaller-00275-gbec6f00f120e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0033:0x7f0c03850d66
Code: f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 49 29 f1 <47> 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48 83 c0 01
RSP: 002b:00007f0c048574a0 EFLAGS: 00000202
RAX: 0000000000f489cf RBX: 00007f0c04857540 RCX: 000000000000004a
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007f0c048575e0
RBP: 0000000000000102 R08: 00007f0bf9200000 R09: 0000000000f489ce
R10: 0000000000000000 R11: 00007f0c04857550 R12: 0000000000000001
R13: 00007f0c03a2bfc0 R14: 0000000000000000 R15: 00007f0c048575e0
FS: 00007f0c048586c0 GS: 0000000000000000