INFO: task syz.1.4582:22902 blocked for more than 143 seconds.
Not tainted 6.16.0-rc4-next-20250704-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.4582 state:D stack:25096 pid:22902 tgid:22902 ppid:21522 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5318 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6701
__schedule_loop kernel/sched/core.c:6779 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6794
request_wait_answer fs/fuse/dev.c:566 [inline]
__fuse_request_send fs/fuse/dev.c:580 [inline]
__fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:674
fuse_simple_request fs/fuse/fuse_i.h:1230 [inline]
fuse_flush+0x5d4/0x800 fs/fuse/file.c:475
filp_flush+0xba/0x190 fs/open.c:1546
filp_close+0x1d/0x40 fs/open.c:1559
__range_close fs/file.c:767 [inline]
__do_sys_close_range fs/file.c:826 [inline]
__se_sys_close_range+0x359/0x650 fs/file.c:790
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: 0033:0x7fefd758e929
RSP: 002b:00007fffc3a6c708 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00000000000dbbfe RCX: 00007fefd758e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fefd77b7ba0 R08: 0000000000000001 R09: 0000000ac3a6c9ff
R10: 00007fefd7400000 R11: 0000000000000246 R12: 00007fefd77b5fac
R13: 00007fefd77b5fa0 R14: ffffffffffffffff R15: 00007fffc3a6c820
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e53bf60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e53bf60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e53bf60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5612:
#0: ffff8880351ca0a0 (&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
1 lock held by udevd/5989:
#0: ffff888025a36358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
3 locks held by kworker/1:4/13759:
#0: ffff88801a880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff88801a880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc90003367bc0 (xfrm_state_gc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc90003367bc0 (xfrm_state_gc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffffffff8e541a78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e541a78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967
1 lock held by syz.8.4881/25626:
#0: ffff888046e740e0 (&type->s_umount_key#77/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:345
2 locks held by syz.3.5190/28350:
#0: ffff888042e340e0 (&type->s_umount_key#64/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:345
#1: ffff888025a36358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
2 locks held by syz.4.5372/30118:
2 locks held by sed/30135:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-next-20250704-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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/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: 30140 Comm: dhcpcd-run-hook Not tainted 6.16.0-rc4-next-20250704-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:check_preemption_disabled+0x49/0x120 lib/smp_processor_id.c:55
Code: 8b 0d 4b 9a 67 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 2b 9a 67 07 48 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f <5d> e9 91 bf 02 00 cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24
RSP: 0018:ffffc9000cb17168 EFLAGS: 00000286
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 709d7d9668d06a00
RDX: 0000000000000000 RSI: ffffffff8c04be60 RDI: ffffffff8c04be20
RBP: ffffffff8172ec65 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc9000cb17358 R11: ffffffff81acc420 R12: 0000000000000002
R13: ffffffff8e53bf60 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881258af000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4f828c7368 CR3: 00000000446b8000 CR4: 00000000003526f0
DR0: 00000000000000f8 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:751
trace_lock_acquire include/trace/events/lock.h:24 [inline]
lock_acquire+0x5f/0x360 kernel/locking/lockdep.c:5834
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+0x3e/0x60 mm/kasan/common.c:47
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548
__call_rcu_common kernel/rcu/tree.c:3100 [inline]
call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3220
slab_free_hook mm/slub.c:2381 [inline]
slab_free mm/slub.c:4680 [inline]
kmem_cache_free+0x309/0x400 mm/slub.c:4782
anon_vma_free mm/rmap.c:137 [inline]
__put_anon_vma+0x12b/0x2d0 mm/rmap.c:2766
put_anon_vma include/linux/rmap.h:117 [inline]
unlink_anon_vmas+0x503/0x670 mm/rmap.c:444
free_pgtables+0x7bf/0xaf0 mm/memory.c:419
exit_mmap+0x444/0xb50 mm/mmap.c:1294
__mmput+0x118/0x420 kernel/fork.c:1120
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x648/0x2300 kernel/exit.c:947
do_group_exit+0x21c/0x2d0 kernel/exit.c:1100
__do_sys_exit_group kernel/exit.c:1111 [inline]
__se_sys_exit_group kernel/exit.c:1109 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1109
x64_sys_call+0x21f7/0x2200 arch/x86/include/generated/asm/syscalls_64.h:232
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: 0033:0x7f4f826f76c5
Code: Unable to access opcode bytes at 0x7f4f826f769b.
RSP: 002b:00007ffee6cd7e38 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ffee6cd8104 RCX: 00007f4f826f76c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 0000000000000003 R08: 00007ffee6cd7f30 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffee6cd8170 R14: 00007f4f82907000 R15: 000055d9ed9fed98