INFO: task syz.3.12867:32343 blocked for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.12867 state:D stack:27448 pid:32343 tgid:32342 ppid:5618 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f9/0x5500 kernel/sched/core.c:7197
__schedule_loop kernel/sched/core.c:7276 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7572
rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1667
__rt_mutex_slowlock kernel/locking/rtmutex.c:1744 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1784 [inline]
rt_mutex_slowlock+0x2dc/0x780 kernel/locking/rtmutex.c:1824
__rt_mutex_lock kernel/locking/rtmutex.c:1839 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:541 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:559
nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
nfsd_umount+0x41/0x60 fs/nfsd/nfsctl.c:1365
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xf3/0x4d0 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f195fffcdd9
RSP: 002b:00007f195e24e028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffec RBX: 00007f1960275fa0 RCX: 00007f195fffcdd9
RDX: 0000200000000040 RSI: 00002000000001c0 RDI: 0000000000000000
RBP: 00007f1960092d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000001000016 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1960276038 R14: 00007f1960275fa0 R15: 00007ffdabf90288
Showing all locks held in the system:
1 lock held by khungtaskd/39:
#0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by getty/5367:
#0: ffff88802d0e90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
9 locks held by syz-executor/5617:
#0: ffffffff8e2996d0 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1534 [inline]
#0: ffffffff8e2996d0 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x130/0x4a0 kernel/fork.c:1587
#1: ffff8880119510b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
#1: ffff8880119510b0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x181/0x1d50 mm/mmap.c:1739
#2: ffff888029e12ab0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:544 [inline]
#2: ffff888029e12ab0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x26f/0x1d50 mm/mmap.c:1746
#3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#3: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290
#4: ffff88802bad1118 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#4: ffff88802bad1118 (ptlock_ptr(ptdesc)#2){+.+.}-{3:3}, at: pte_offset_map_lock+0x13d/0x210 mm/pgtable-generic.c:404
#5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#5: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
#6: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#6: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#6: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x200 mm/pgtable-generic.c:290
#7: ffff888036d46718 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pte_range mm/memory.c:1272 [inline]
#7: ffff888036d46718 (ptlock_ptr(ptdesc)#2/1){+.+.}-{3:3}, at: copy_pmd_range+0x5ae/0x5550 mm/memory.c:1408
#8: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#8: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#8: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#8: ffffffff8e1c8240 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock_nested+0x1de/0x3f0 kernel/locking/spinlock_rt.c:65
3 locks held by kworker/0:7/5717:
#0: ffff88813fe0e938 ((wq_completion)events_freezable){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3281
#1: ffffc9000512fc40 ((work_completion)(&hcd->wakeup_work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3282
#2: ffff888029fba210 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1038 [inline]
#2: ffff888029fba210 (&dev->mutex){....}-{4:4}, at: usb_remote_wakeup+0x23/0x120 drivers/usb/core/hub.c:3886
2 locks held by syz.2.11445/29391:
#0: ffffffff8f6024c0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8e4ec158 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_listener_set_doit+0x13e/0x1630 fs/nfsd/nfsctl.c:1954
2 locks held by syz.3.12867/32343:
#0: ffff88805dbe40d0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88805dbe40d0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88805dbe40d0 (&type->s_umount_key#91){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e4ec158 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
1 lock held by syz.5.14605/3804:
#0: ffff88805dbe40d0 (&type->s_umount_key#91){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88805dbe40d0 (&type->s_umount_key#91){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 7b 6b 02 e9 83 cc 03 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 43 cb 15 00 fb f4 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffc900001e7e20 EFLAGS: 00000242
RAX: 00000000000afcfd RBX: ffffffff8199caaa RCX: 0000000080000001
RDX: 0000000000000001 RSI: ffffffff8d747b0a RDI: ffffffff8baa6d60
RBP: ffffc900001e7f10 R08: ffff8880b8733d1b R09: 1ffff110170e67a3
R10: dffffc0000000000 R11: ffffed10170e67a4 R12: 0000000000000001
R13: 1ffff11003b5ab88 R14: 0000000000000001 R15: 1ffff11003b5ab88
FS: 0000000000000000(0000) GS:ffff888125dc7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb7916f7dac CR3: 0000000042afe000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:766 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:767
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x36a/0x5f0 kernel/sched/idle.c:352
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:451
start_secondary+0x101/0x110 arch/x86/kernel/smpboot.c:312
common_startup_64+0x13e/0x157