INFO: task syz-executor:7782 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-next-20250717-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21928 pid:7782 tgid:7782 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5314 [inline]
__schedule+0x16fd/0x4cf0 kernel/sched/core.c:6697
__schedule_loop kernel/sched/core.c:6775 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6790
schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75
do_wait_for_common kernel/sched/completion.c:100 [inline]
__wait_for_common kernel/sched/completion.c:121 [inline]
wait_for_common kernel/sched/completion.c:132 [inline]
wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:153
kthread_stop+0x194/0x5f0 kernel/kthread.c:790
bch2_copygc_stop+0x4f/0x150 fs/bcachefs/movinggc.c:436
__bch2_fs_read_only+0x4a/0x4f0 fs/bcachefs/super.c:303
bch2_fs_read_only+0x403/0xa40 fs/bcachefs/super.c:389
__bch2_fs_stop+0xc9/0x8f0 fs/bcachefs/super.c:700
generic_shutdown_super+0x132/0x2c0 fs/super.c:643
bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2586
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1378
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1348d8fc57
RSP: 002b:00007fff09eefc68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f1348e10a8d RCX: 00007f1348d8fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff09eefd20
RBP: 00007fff09eefd20 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff09ef0db0
R13: 00007f1348e10a8d R14: 000000000003ecd8 R15: 00007fff09ef0df0
Showing all locks held in the system:
7 locks held by kworker/u8:1/13:
1 lock held by khungtaskd/31:
#0: ffffffff8e13e2e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13e2e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13e2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by acpid/5201:
#0: ffff888067e47118 (&evdev->mutex){+.+.}-{4:4}, at: evdev_close_device drivers/input/evdev.c:402 [inline]
#0: ffff888067e47118 (&evdev->mutex){+.+.}-{4:4}, at: evdev_release+0x706/0x800 drivers/input/evdev.c:447
#1: ffff88802836f2c0 (&dev->mutex#2){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:225 [inline]
#1: ffff88802836f2c0 (&dev->mutex#2){+.+.}-{4:4}, at: input_close_device+0x4c/0x280 drivers/input/input.c:645
#2: ffffffff8e143e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e143e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967
2 locks held by getty/5605:
#0: ffff88814cb710a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by syz-executor/5855:
2 locks held by syz-executor/7782:
#0: ffff88807a5920e0 (&type->s_umount_key#72){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88807a5920e0 (&type->s_umount_key#72){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88807a5920e0 (&type->s_umount_key#72){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
#1: ffff888044700278 (&c->state_lock){++++}-{4:4}, at: class_rwsem_write_constructor include/linux/rwsem.h:257 [inline]
#1: ffff888044700278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xc1/0x8f0 fs/bcachefs/super.c:699
2 locks held by bch-copygc/loop/8936:
#0: ffff8880447043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#0: ffff8880447043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#0: ffff8880447043a8 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0xaf/0x220 fs/bcachefs/btree_iter.c:3293
#1: ffff888044726710 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x53f/0x1e00 fs/bcachefs/btree_update_interior.c:1196
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250717-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+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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5855 Comm: syz-executor Not tainted 6.16.0-rc6-next-20250717-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:get_current arch/x86/include/asm/current.h:25 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_const_cmp8+0x8/0x90 kernel/kcov.c:321
Code: 48 89 44 11 20 c3 cc cc cc cc cc 0f 1f 80 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0c 25 08 e0 a3 92 65 8b 15 88 29 e4 10 81 e2 00 01 ff 00
RSP: 0018:ffffc90000a08420 EFLAGS: 00000246
RAX: ffffffff895dd2f7 RBX: ffff88805cabcc80 RCX: ffff888032c30000
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000a08770 R08: 0000000000000000 R09: ffffffff895de9ab
R10: dffffc0000000000 R11: fffffbfff1f458e7 R12: dffffc0000000000
R13: 1ffff1100b95799b R14: ffff88805cabccd8 R15: ffff888032f6a000
FS: 0000555563f98500(0000) GS:ffff888125ce2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc449d802d8 CR3: 000000007647e000 CR4: 00000000003526f0
Call Trace:
skb_dst_is_noref include/linux/skbuff.h:1199 [inline]
skb_dst_force+0x47/0x360 include/net/dst.h:314
__dev_queue_xmit+0x7e6/0x3b50 net/core/dev.c:4670
neigh_output include/net/neighbour.h:542 [inline]
ip6_finish_output2+0x11fb/0x16a0 net/ipv6/ip6_output.c:141
NF_HOOK include/linux/netfilter.h:317 [inline]
ndisc_send_skb+0xb54/0x1440 net/ipv6/ndisc.c:512
addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4032
call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1747
expire_timers kernel/time/timer.c:1798 [inline]
__run_timers kernel/time/timer.c:2372 [inline]
__run_timer_base+0x61a/0x860 kernel/time/timer.c:2384
run_timer_base kernel/time/timer.c:2393 [inline]
run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
handle_softirqs+0x283/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline]
RIP: 0010:vprintk_emit+0x58f/0x7a0 kernel/printk/printk.c:2449
Code: 85 32 01 00 00 e8 81 88 1f 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 70 88 1f 00 eb 06 e8 69 88 1f 00 fb 48 c7 c7 60 25 13 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 b9 35
RSP: 0018:ffffc900046ff940 EFLAGS: 00000293
RAX: ffffffff81a02947 RBX: ffffffff81a02804 RCX: ffff888032c30000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e132560
RBP: ffffc900046ffa50 R08: ffffffff8fa2c737 R09: 1ffffffff1f458e6
R10: dffffc0000000000 R11: fffffbfff1f458e7 R12: dffffc0000000000
R13: 1ffff920008dff2c R14: 0000000000000200 R15: 000000000000004c
_printk+0xcf/0x120 kernel/printk/printk.c:2475
__ext4_msg+0x293/0x2a0 fs/ext4/super.c:981
ext4_put_super+0xb8/0xc40 fs/ext4/super.c:1286
generic_shutdown_super+0x132/0x2c0 fs/super.c:643
kill_block_super+0x44/0x90 fs/super.c:1766
ext4_kill_sb+0x68/0xb0 fs/ext4/super.c:7391
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1378
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fefd8f8fc57
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffd17743fb8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fefd9010a8d RCX: 00007fefd8f8fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd17744070
RBP: 00007ffd17744070 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffd17745100
R13: 00007fefd9010a8d R14: 0000000000064fdb R15: 00007ffd17745140