INFO: task syz.4.3355:18152 blocked for more than 167 seconds.
Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.3355 state:D stack:23808 pid:18152 tgid:18152 ppid:17738 flags:0x00000000
Call Trace:
context_switch kernel/sched/core.c:5322 [inline]
__schedule+0x1895/0x4b30 kernel/sched/core.c:6682
__schedule_loop kernel/sched/core.c:6759 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6774
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6831
__mutex_lock_common kernel/locking/mutex.c:684 [inline]
__mutex_lock+0x6a7/0xd70 kernel/locking/mutex.c:752
pipe_release+0x48/0x320 fs/pipe.c:727
__fput+0x23f/0x880 fs/file_table.c:431
task_work_run+0x24f/0x310 kernel/task_work.c:228
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbb4a57dff9
RSP: 002b:00007fffca277ea8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fbb4a737a80 RCX: 00007fbb4a57dff9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fbb4a737a80 R08: 0000000000000006 R09: 00007fffca27819f
R10: 00000000003ffc7c R11: 0000000000000246 R12: 0000000000169997
R13: 00007fffca277fb0 R14: 0000000000000032 R15: ffffffffffffffff
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8e937de0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6720
2 locks held by getty/4989:
#0: ffff888031d120a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
2 locks held by syz.2.2874/16735:
#0: ffffffff8fd39430 (cb_lock){++++}-{3:3}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1218
#1: ffffffff8ec19008 (nfsd_mutex){+.+.}-{3:3}, at: nfsd_nl_listener_set_doit+0x12d/0x1a90 fs/nfsd/nfsctl.c:1964
1 lock held by udevd/17436:
1 lock held by syz-executor/17740:
1 lock held by syz.4.3355/18152:
#0: ffff88804d2a8c68 (&pipe->mutex){+.+.}-{3:3}, at: pipe_release+0x48/0x320 fs/pipe.c:727
1 lock held by syz.4.3355/18153:
#0: ffff88804d2a8c68 (&pipe->mutex){+.+.}-{3:3}, at: splice_file_to_pipe+0x2e/0x500 fs/splice.c:1292
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xff4/0x1040 kernel/hung_task.c:379
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17737 Comm: syz-executor Not tainted 6.12.0-rc2-syzkaller-00631-g6d858708d465 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:__lock_acquire+0x84/0x2050 kernel/locking/lockdep.c:5065
Code: 89 54 24 54 89 5c 24 68 4c 89 f8 48 c1 e8 03 80 3c 30 00 74 12 4c 89 ff e8 a9 3a 8e 00 48 be 00 00 00 00 00 fc ff df 49 8b 07 <48> c7 c1 d0 c6 e3 93 48 39 c8 0f 84 7c 13 00 00 8b 0d 96 e4 0f 0d
RSP: 0018:ffffc900036cf710 EFLAGS: 00000046
RAX: ffff8880b8639818 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffff8880b8739818
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
R10: dffffc0000000000 R11: fffffbfff203a236 R12: ffff888072961e00
R13: 0000000000000001 R14: 0000000000000000 R15: ffff8880b8739818
FS: 000055555c36b500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4edffb0f40 CR3: 0000000069d50000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825
local_lock_acquire include/linux/local_lock_internal.h:29 [inline]
refill_obj_stock+0x13d/0x650 mm/memcontrol.c:2852
obj_cgroup_uncharge mm/memcontrol.c:2923 [inline]
__memcg_slab_free_hook+0x1df/0x310 mm/memcontrol.c:3010
memcg_slab_free_hook mm/slub.c:2182 [inline]
slab_free mm/slub.c:4576 [inline]
kmem_cache_free+0x234/0x420 mm/slub.c:4681
__sigqueue_free kernel/signal.c:451 [inline]
collect_signal kernel/signal.c:594 [inline]
__dequeue_signal+0x4ac/0x5c0 kernel/signal.c:616
dequeue_signal+0x1e0/0x680 kernel/signal.c:637
get_signal+0x604/0x1740 kernel/signal.c:2797
arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f54fcdb00e5
Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 c6 57 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 1f 58 ff ff 48 8b 04 24 48 83 c4 28 f7 d8
RSP: 002b:00007fffccb07790 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 000000000000005e RCX: 00007f54fcdb00e5
RDX: 00007fffccb077d0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fffccb0782c R08: 0000000000000000 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032
R13: 0000000000169c94 R14: 0000000000169c61 R15: 00007fffccb07880