INFO: task syz.7.2513:21592 blocked for more than 143 seconds.
Not tainted 6.16.0-rc5-next-20250710-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.2513 state:D stack:25096 pid:21592 tgid:21592 ppid:10999 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5314 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6697
__schedule_loop kernel/sched/core.c:6775 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6790
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:1547
filp_close+0x1d/0x40 fs/open.c:1560
__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: 0033:0x7fddb3b8e929
RSP: 002b:00007ffeb98471a8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007fddb3db7ba0 RCX: 00007fddb3b8e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fddb3db7ba0 R08: 00000000000000c0 R09: 0000000cb984749f
R10: 00007fddb3db7ac0 R11: 0000000000000246 R12: 000000000007eb2d
R13: 00007fddb3db5fa0 R14: ffffffffffffffff R15: 00007ffeb98472c0
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e53c4e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e53c4e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e53c4e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5613:
#0: ffff88814d0320a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
6 locks held by kworker/0:6/8748:
#0: ffff8880222b1d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff8880222b1d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc9000e897bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc9000e897bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff888144729198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#2: ffff888144729198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5894
#3: ffff88814472d518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline]
#3: ffff88814472d518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5463 [inline]
#3: ffff88814472d518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
#3: ffff88814472d518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5866 [inline]
#3: ffff88814472d518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21a3/0x4a00 drivers/usb/core/hub.c:5948
#4: ffff8881443ad568 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
#4: ffff8881443ad568 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
#4: ffff8881443ad568 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5866 [inline]
#4: ffff8881443ad568 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21cb/0x4a00 drivers/usb/core/hub.c:5948
#5: ffffffff8f1f5390 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x163/0x1750 drivers/usb/core/hub.c:3066
2 locks held by syz.8.2616/23021:
#0: ffff888028a02428 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88805b3e6348 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff88805b3e6348 (&sb->s_type->i_mutex_key#25){+.+.}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
1 lock held by syz.9.3305/30133:
#0: ffffffff8e541f00 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3794
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc5-next-20250710-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+0x711/0x8a0 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: 30224 Comm: syz.1.3321 Not tainted 6.16.0-rc5-next-20250710-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:css_rstat_updated+0x5/0x4e0 kernel/cgroup/rstat.c:65
Code: 8b e8 bf da 6b 00 b8 6b 00 00 00 5b c3 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <48> 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec a0 00 00
RSP: 0018:ffffc90000ac76e8 EFLAGS: 00000082
RAX: 0000000000000001 RBX: ffff88807ecac000 RCX: 1fa41bbae23df000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff88807ecac000
RBP: 0000000000000001 R08: ffffffff8fe48b37 R09: 1ffffffff1fc9166
R10: dffffc0000000000 R11: fffffbfff1fc9167 R12: dffffc0000000000
R13: 0000607eda4c0e98 R14: 0000000000004bec R15: ffffe8ffffd58ea8
FS: 0000555571dc3500(0000) GS:ffff888125898000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f66e5b82178 CR3: 000000003558a000 CR4: 00000000003526f0
Call Trace:
cgroup_base_stat_cputime_account_end kernel/cgroup/rstat.c:585 [inline]
__cgroup_account_cputime+0xc2/0x120 kernel/cgroup/rstat.c:596
update_curr+0x380/0x8b0 kernel/sched/fair.c:1230
dequeue_entity+0x27/0x1690 kernel/sched/fair.c:5384
dequeue_entities+0x1fa/0x1510 kernel/sched/fair.c:6990
dequeue_task_fair+0x205/0x580 kernel/sched/fair.c:7089
block_task kernel/sched/core.c:2119 [inline]
try_to_block_task kernel/sched/core.c:6530 [inline]
__schedule+0x5a7/0x4d00 kernel/sched/core.c:6646
__schedule_loop kernel/sched/core.c:6775 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6790
do_nanosleep+0x1c7/0x600 kernel/time/hrtimer.c:2100
hrtimer_nanosleep+0x169/0x360 kernel/time/hrtimer.c:2147
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1399 [inline]
__se_sys_clock_nanosleep+0x2f1/0x380 kernel/time/posix-timers.c:1376
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: 0033:0x7f99cb3c11e5
Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 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 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8
RSP: 002b:00007ffcb9236bf0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 00007f99cb5b5fa0 RCX: 00007f99cb3c11e5
RDX: 00007ffcb9236c30 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f99cb5b7ba0 R08: 0000000000000000 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000293 R12: 00000000000a51fa
R13: 00007f99cb5b5fa0 R14: ffffffffffffffff R15: 00007ffcb9236d70
vkms_vblank_simulate: vblank timer overrun