INFO: task syz-executor:6040 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-executor state:D stack:22040 pid:6040 tgid:6040 ppid:1 task_flags:0x400140 flags:0x00004004
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
wb_wait_for_completion+0x15f/0x260 fs/fs-writeback.c:216
__writeback_inodes_sb_nr+0x1f6/0x250 fs/fs-writeback.c:2747
sync_filesystem+0xa3/0x230 fs/sync.c:54
generic_shutdown_super+0x6f/0x2c0 fs/super.c:621
bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2620
deactivate_locked_super+0xb9/0x130 fs/super.c:473
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1431
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218
do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f861918fc97
RSP: 002b:00007fff509be648 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f861921089d RCX: 00007f861918fc97
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff509be700
RBP: 00007fff509be700 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff509bf790
R13: 00007f861921089d R14: 000000000004e45e R15: 00007fff509bf7d0
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998
2 locks held by kworker/u8:0/12:
#0: ffff8881422a3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8881422a3948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90000117c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000117c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
1 lock held by khungtaskd/32:
#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: ffff8880304d60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/6040:
#0: ffff8880690ea0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff8880690ea0e0 (&type->s_umount_key#54){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff8880690ea0e0 (&type->s_umount_key#54){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
1 lock held by udevd/7372:
2 locks held by syz-executor/9254:
#0: ffff88802fe720e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88802fe720e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88802fe720e0 (&type->s_umount_key#66){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
#1: ffffffff8df41200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774
2 locks held by syz-executor/9775:
#0: ffff88806bd4a0e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock fs/super.c:56 [inline]
#0: ffff88806bd4a0e0 (&type->s_umount_key#66){++++}-{4:4}, at: __super_lock_excl fs/super.c:71 [inline]
#0: ffff88806bd4a0e0 (&type->s_umount_key#66){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:505
#1: ffffffff8df41200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3774
2 locks held by syz.6.669/12767:
4 locks held by dhcpcd-run-hook/12815:
#0: ffff8880b88399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605
#1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987
#2: ffff88802e4b1498 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
#2: ffff88802e4b1498 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: __pte_offset_map_lock+0x106/0x1e0 mm/pgtable-generic.c:402
#3: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#3: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#3: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: page_table_check_set+0x16b/0x710 mm/page_table_check.c:112
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 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: 5192 Comm: udevd 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: 0010:syscall_return_via_sysret+0x1a/0x87
Code: 1c 00 00 e8 90 b2 4e 0a 84 c0 0f 84 38 15 00 00 66 90 b9 48 00 00 00 65 48 8b 15 99 2a 72 11 83 e2 fe 89 d0 48 c1 ea 20 0f 30 <41> 5f 41 5e 41 5d 41 5c 5d 5b 41 5b 41 5a 41 59 41 58 58 59 5a 5e
RSP: 0018:ffffc90003437f58 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000048
RDX: 0000000000000000 RSI: 00007fffffffefff RDI: ffffffff8bc0ff20
RBP: 0000000000000000 R08: ffffffff8f7da977 R09: 1ffffffff1efb52e
R10: dffffc0000000000 R11: fffffbfff1efb52f R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 00007fb934b6d880(0000) GS:ffff888126200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6e90873eb8 CR3: 000000004a284000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
RIP: 0033:0x7fb9344f0d23
Code: 8b 05 d9 00 10 00 64 c7 00 16 00 00 00 31 c0 eb b0 66 0f 1f 44 00 00 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 a1 00 10 00 f7 d8
RSP: 002b:00007fffb95865f8 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: 0000000000000118 RBX: 0000557b768db090 RCX: 00007fb9344f0d23
RDX: 0000000000008000 RSI: 0000557b768db0c0 RDI: 000000000000000d
RBP: 0000557b768db094 R08: 00007fb9345f1ac0 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000293 R12: 0000557b768db0c0
R13: fffffffffffffe68 R14: 0000000000000002 R15: 00007fffb95868a0