INFO: task syz.4.615:8708 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.615 state:D stack:25784 pid:8708 tgid:8706 ppid:5871 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
super_lock+0x1c8/0x3b0 fs/super.c:115
__iterate_supers+0x126/0x290 fs/super.c:923
ksys_sync+0x94/0x150 fs/sync.c:102
__ia32_sys_sync+0xe/0x20 fs/sync.c:113
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: 0033:0x7f306118eba9
RSP: 002b:00007f3061fd7038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f30613d5fa0 RCX: 00007f306118eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f30613d5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f30613d6038 R14: 00007f30613d5fa0 R15: 00007fffab743ec8
Showing all locks held in the system:
6 locks held by kworker/1:0/24:
#0: ffff88801dac8548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801dac8548 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffff8880289e4198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:911 [inline]
#2: ffff8880289e4198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20 drivers/usb/core/hub.c:5898
#3: ffff8880289e7518 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3251 [inline]
#3: ffff8880289e7518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5463 [inline]
#3: ffff8880289e7518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
#3: ffff8880289e7518 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline]
#3: ffff8880289e7518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20 drivers/usb/core/hub.c:5952
#4: ffff88802885cf68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5464 [inline]
#4: ffff88802885cf68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
#4: ffff88802885cf68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5870 [inline]
#4: ffff88802885cf68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20 drivers/usb/core/hub.c:5952
#5: ffff8880b8639f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:644
1 lock held by khungtaskd/31:
#0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5621:
#0: ffff88814da360a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036ce2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
5 locks held by syz.8.593/8617:
1 lock held by syz.3.1031/10293:
3 locks held by syz.1.1023/10315:
#0: ffffffff8fa3dde8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8fa3dde8 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8fa3dde8 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f539c08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f539c08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f539c08 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056
#2: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x711/0x8a0 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8617 Comm: syz.8.593 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:check_kcov_mode kernel/kcov.c:183 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x18/0x70 kernel/kcov.c:217
Code: cc cc 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 b0 a0 92 65 8b 15 38 01 e1 10 <81> e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00
RSP: 0018:ffffc9000447f998 EFLAGS: 00000282
RAX: ffffffff81ac72e3 RBX: ffffc9000447fa80 RCX: ffff888027285a00
RDX: 0000000080000000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc9000447fa50 R08: ffffffff8fa3a137 R09: 1ffffffff1f47426
R10: dffffc0000000000 R11: fffffbfff1f47427 R12: ffffc9000447f9e0
R13: 000000003b9aca00 R14: fcffd5774b0d128f R15: 0de2982944c6c6ad
FS: 00007f52703f36c0(0000) GS:ffff888125c15000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c43625e CR3: 000000002c962000 CR4: 0000000000350ef0
Call Trace:
set_normalized_timespec64+0x113/0x1a0 kernel/time/time.c:507
inode_set_ctime_to_ts+0x126/0x2f0 fs/inode.c:2665
inode_set_ctime include/linux/fs.h:1779 [inline]
v9fs_stat2inode_dotl+0x4f6/0xad0 fs/9p/vfs_inode_dotl.c:656
v9fs_qid_iget_dotl fs/9p/vfs_inode_dotl.c:128 [inline]
v9fs_inode_from_fid_dotl+0x206/0x2b0 fs/9p/vfs_inode_dotl.c:154
v9fs_get_new_inode_from_fid fs/9p/v9fs.h:251 [inline]
v9fs_mount+0x6eb/0xa50 fs/9p/vfs_super.c:144
legacy_get_tree+0xfd/0x1a0 fs/fs_context.c:666
vfs_get_tree+0x92/0x2b0 fs/super.c:1815
do_new_mount+0x2a2/0x9e0 fs/namespace.c:3808
do_mount fs/namespace.c:4136 [inline]
__do_sys_mount fs/namespace.c:4347 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4324
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: 0033:0x7f526f58eba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f52703f3038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f526f7d6270 RCX: 00007f526f58eba9
RDX: 0000200000000b80 RSI: 0000200000000040 RDI: 0000000000000000
RBP: 00007f526f611e19 R08: 0000200000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f526f7d6308 R14: 00007f526f7d6270 R15: 00007ffd45ce6d98
vkms_vblank_simulate: vblank timer overrun