INFO: task syz.1.6912:20216 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.1.6912 state:D stack:28576 pid:20216 tgid:20213 ppid:18866 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289
rt_mutex_slowlock_block+0x508/0x680 kernel/locking/rtmutex.c:1647
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked kernel/locking/rtmutex.c:1760 [inline]
rt_mutex_slowlock+0x2dc/0x7b0 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
__mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline]
mutex_lock_nested+0x168/0x1d0 kernel/locking/rtmutex_api.c:552
nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
nfsd_umount+0x41/0x60 fs/nfsd/nfsctl.c:1364
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+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdfe615c819
RSP: 002b:00007fdfe43ae028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffec RBX: 00007fdfe63d5fa0 RCX: 00007fdfe615c819
RDX: 0000200000000040 RSI: 00002000000001c0 RDI: 0000000000000000
RBP: 00007fdfe61f2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000001000016 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdfe63d6038 R14: 00007fdfe63d5fa0 R15: 00007ffe6287bb28
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb9c0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by udevd/5166:
2 locks held by getty/5555:
#0: ffff888036f270a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
9 locks held by syz-executor/5998:
2 locks held by syz-executor/5999:
#0: ffffffff8de0b170 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x2360/0x3cd0 kernel/fork.c:2322
#1: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: write_lock_irq include/linux/rwlock_rt.h:115 [inline]
#1: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: copy_process+0x2482/0x3cd0 kernel/fork.c:2369
2 locks held by syz-executor/6001:
#0: ffffffff8de0b170 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x2360/0x3cd0 kernel/fork.c:2322
#1: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: write_lock_irq include/linux/rwlock_rt.h:115 [inline]
#1: ffffffff8da0c0a8 (tasklist_lock){++++}-{3:3}, at: copy_process+0x2482/0x3cd0 kernel/fork.c:2369
2 locks held by syz.4.3155/12327:
#0: ffffffff8f1cb1e0 (cb_lock){++++}-{4:4}, at: genl_rcv+0x19/0x40 net/netlink/genetlink.c:1217
#1: ffffffff8e0e6658 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_nl_threads_set_doit+0x2b5/0x9a0 fs/nfsd/nfsctl.c:1607
10 locks held by syz-executor/13177:
2 locks held by syz.1.6912/20216:
#0: ffff88805cd7e0d0 (&type->s_umount_key#99){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88805cd7e0d0 (&type->s_umount_key#99){++++}-{4:4}, at: __super_lock_excl fs/super.c:73 [inline]
#0: ffff88805cd7e0d0 (&type->s_umount_key#99){++++}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:508
#1: ffffffff8e0e6658 (nfsd_mutex){+.+.}-{4:4}, at: nfsd_shutdown_threads+0x4e/0xd0 fs/nfsd/nfssvc.c:576
1 lock held by syz.6.7818/22088:
#0: ffff88805cd7e0d0 (&type->s_umount_key#99){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88805cd7e0d0 (&type->s_umount_key#99){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
4 locks held by syz.7.10601/27942:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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:161 [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:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 5998 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:page_table_check_set+0x2e1/0x610 mm/page_table_check.c:121
Code: 89 fe e8 52 77 92 ff 45 85 ff 0f 85 4e 02 00 00 48 8d 7b 04 be 04 00 00 00 e8 4b 97 f8 ff 41 bf 01 00 00 00 f0 44 0f c1 7b 04 <41> 8d 77 01 31 ff e8 24 77 92 ff 41 ff c7 0f 88 28 02 00 00 e8 66
RSP: 0018:ffffc90004da7308 EFLAGS: 00000206
RAX: ffffffff82321301 RBX: ffff88801ca6ec58 RCX: ffffffff823213e5
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff88801ca6ec5c
RBP: ffff88801ca6ec10 R08: ffff88801ca6ec5f R09: 1ffff1100394dd8b
R10: dffffc0000000000 R11: ffffed100394dd8c R12: 0000000000000001
R13: 0000000000057c8d R14: 0000000000000001 R15: 0000000000000004
FS: 0000555564ce4500(0000) GS:ffff888126436000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f461a0d56b8 CR3: 000000003be68000 CR4: 00000000003526f0
Call Trace:
page_table_check_ptes_set include/linux/page_table_check.h:83 [inline]
set_ptes include/linux/pgtable.h:413 [inline]
__copy_present_ptes mm/memory.c:1115 [inline]
copy_present_ptes mm/memory.c:1194 [inline]
copy_pte_range mm/memory.c:1317 [inline]
copy_pmd_range+0x3ad6/0x7c00 mm/memory.c:1405
copy_pud_range mm/memory.c:1442 [inline]
copy_p4d_range mm/memory.c:1466 [inline]
copy_page_range+0xaf4/0x1120 mm/memory.c:1552
dup_mmap+0xf4c/0x1d50 mm/mmap.c:1841
dup_mm kernel/fork.c:1531 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1583
copy_process+0x18be/0x3cd0 kernel/fork.c:2223
kernel_clone+0x249/0x840 kernel/fork.c:2653
__do_sys_clone kernel/fork.c:2794 [inline]
__se_sys_clone kernel/fork.c:2778 [inline]
__x64_sys_clone+0x1b6/0x230 kernel/fork.c:2778
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2fe2ce5292
Code: 89 e7 e8 71 8b f7 ff 45 31 c0 31 d2 31 f6 64 48 8b 04 25 10 00 00 00 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 66 89 c5 85 c0 75 3b 64 48 8b 04 25 10 00 00
RSP: 002b:00007fff25a9e160 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fff25a9e160 RCX: 00007f2fe2ce5292
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007fff25a9e2ec R08: 0000000000000000 R09: 0000000000000001
R10: 0000555564ce47d0 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 000000000009333f R15: 00007fff25a9e340