INFO: task syz.1.3959:24450 blocked for more than 144 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.3959 state:D stack:26496 pid:24450 tgid:24450 ppid:19868 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x15dd/0x52d0 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7008
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065
__mutex_lock_common kernel/locking/mutex.c:692 [inline]
__mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776
bdev_release+0x1a9/0x650 block/bdev.c:1144
blkdev_release+0x15/0x20 block/fops.c:705
__fput+0x44f/0xa70 fs/file_table.c:469
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: 0033:0x7f3cab39c799
RSP: 002b:00007fff880fecd8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f3cab617da0 RCX: 00007f3cab39c799
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f3cab617da0 R08: 00007f3cab616038 R09: 0000000000000000
R10: 00000000003ffc50 R11: 0000000000000246 R12: 000000000019e583
R13: 00007f3cab61609c R14: 000000000019e365 R15: 00007f3cab616090
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5576:
#0: ffff888032e5e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000331e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by udevd/5847:
#0: ffff888026bb0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961
1 lock held by udevd/6080:
#0: ffff888026bb4358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:961
2 locks held by kworker/u9:1/14661:
#0: ffff888027036948 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff888027036948 ((wq_completion)nbd1-recv){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc90006487c40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc90006487c40 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
3 locks held by udevd/23149:
1 lock held by syz.1.3959/24450:
#0: ffff888026bb4358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1144
2 locks held by sed/26233:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 26230 Comm: dhcpcd-run-hook Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:list_del include/linux/list.h:239 [inline]
RIP: 0010:__rmqueue_pcplist+0x1468/0x1c40 mm/page_alloc.c:3359
Code: 4c 8d 73 08 4c 89 f0 48 c1 e8 03 80 3c 08 00 74 12 4c 89 f7 e8 49 59 0e 00 48 b9 00 00 00 00 00 fc ff df 49 8d 87 e2 00 00 00 <49> 89 06 41 83 fd 20 0f 83 f1 00 00 00 48 8b 7c 24 18 48 89 f8 48
RSP: 0018:ffffc900044e6df8 EFLAGS: 00000246
RAX: dead000000000122 RBX: ffffea0000fd8e48 RCX: dffffc0000000000
RDX: 1ffffffff2023f38 RSI: dffffc0000000000 RDI: ffffea0000fd8e50
RBP: 0000000000000000 R08: 0000000000000080 R09: ffff8880b8640c01
R10: 00000000ffffffff R11: fffff5200089cdd8 R12: ffffea0000aa8650
R13: 0000000000000000 R14: ffffea0000fd8e50 R15: dead000000000040
FS: 00007ff8e4ff9c80(0000) GS:ffff888125459000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc281c30b8 CR3: 000000003b5e6000 CR4: 0000000000350ef0
Call Trace:
rmqueue_pcplist mm/page_alloc.c:3388 [inline]
rmqueue mm/page_alloc.c:3418 [inline]
get_page_from_freelist+0x91d/0x2580 mm/page_alloc.c:3959
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2484
alloc_frozen_pages_noprof mm/mempolicy.c:2555 [inline]
alloc_pages_noprof+0xa8/0x190 mm/mempolicy.c:2575
pagetable_alloc_noprof include/linux/mm.h:3404 [inline]
pmd_alloc_one_noprof include/asm-generic/pgalloc.h:143 [inline]
__pmd_alloc+0x3a/0x5c0 mm/memory.c:6710
pmd_alloc include/linux/mm.h:3320 [inline]
copy_pmd_range+0x7c1c/0x8050 mm/memory.c:1385
copy_pud_range mm/memory.c:1442 [inline]
copy_p4d_range mm/memory.c:1466 [inline]
copy_page_range+0xbe8/0x11f0 mm/memory.c:1552
dup_mmap+0xf40/0x1d90 mm/mmap.c:1841
dup_mm kernel/fork.c:1531 [inline]
copy_mm+0x13b/0x4a0 kernel/fork.c:1583
copy_process+0x18b6/0x3cd0 kernel/fork.c:2223
kernel_clone+0x248/0x8e0 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: 0033:0x7ff8e5193636
Code: 89 df e8 6d e8 f6 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 52 89 c5 85 c0 75 31 64 48 8b 04 25 10 00 00
RSP: 002b:00007ffc281c2b90 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffc281c2b98 RCX: 00007ff8e5193636
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00005588c4ff9c30 R08: 0000000000000000 R09: 0000000000000000
R10: 00007ff8e4ff9f50 R11: 0000000000000246 R12: 00005588c5007358
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000