INFO: task udevd:5140 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23176 pid:5140 ppid:1 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6834
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747
blkdev_get_by_dev+0x11b/0x610 block/bdev.c:801
blkdev_open+0x14e/0x360 block/fops.c:589
do_dentry_open+0x880/0x14b0 fs/open.c:929
do_open fs/namei.c:3683 [inline]
path_openat+0x284f/0x3270 fs/namei.c:3844
do_filp_open+0x1f2/0x430 fs/namei.c:3871
do_sys_openat2+0x134/0x1d0 fs/open.c:1422
do_sys_open fs/open.c:1437 [inline]
__do_sys_openat fs/open.c:1453 [inline]
__se_sys_openat fs/open.c:1448 [inline]
__x64_sys_openat+0x139/0x160 fs/open.c:1448
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f9b1daa7407
RSP: 002b:00007ffe35c603a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9b1e172880 RCX: 00007f9b1daa7407
RDX: 00000000000a0800 RSI: 00005602d65502d0 RDI: ffffffffffffff9c
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00005602c2ab3100 R14: 0000000000000000 R15: 00007ffe35c60630
INFO: task syz.1.710:8258 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.710 state:D stack:27912 pid:8258 ppid:5772 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x15ae/0x4660 kernel/sched/core.c:6701
schedule+0xbd/0x170 kernel/sched/core.c:6775
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6834
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x673/0xc80 kernel/locking/mutex.c:747
blkdev_put+0x100/0x7a0 block/bdev.c:940
blkdev_release+0x84/0x90 block/fops.c:604
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
get_signal+0x11da/0x1390 kernel/signal.c:2687
arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f530199e0d9
RSP: 002b:00007f52ffbf6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f5301c25fa0 RCX: 00007f530199e0d9
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007f5301a35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5301c26038 R14: 00007f5301c25fa0 R15: 00007ffe4a16c448
Showing all locks held in the system:
3 locks held by kworker/u4:1/12:
1 lock held by khungtaskd/29:
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8d131da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
2 locks held by khugepaged/35:
1 lock held by udevd/5140:
#0: ffff888021f8d4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:801
2 locks held by getty/5530:
#0: ffff888031c490a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x428/0x1370 drivers/tty/n_tty.c:2217
2 locks held by kworker/1:3/5811:
#0: ffff8880b8f3c298 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
#1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: psi_sched_switch kernel/sched/stats.h:189 [inline]
#1: ffff8880b8f28a00 (psi_seq){-.-.}-{0:0}, at: __schedule+0x21d3/0x4660 kernel/sched/core.c:6696
1 lock held by udevd/5875:
#0: ffff888021f8d4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x11b/0x610 block/bdev.c:801
2 locks held by kworker/u4:10/6260:
#0: ffff88801baebd38 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#0: ffff88801baebd38 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
#1: ffffc9000b657d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2632 [inline]
#1: ffffc9000b657d00 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x975/0x1600 kernel/workqueue.c:2734
1 lock held by syz.1.710/8258:
#0: ffff888021f8d4c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0x100/0x7a0 block/bdev.c:940
1 lock held by syz.0.1181/9765:
#0: ffff888021f8d4c8 (&disk->open_mutex){+.+.}-{3:3}, at: sync_bdevs+0x1a4/0x320 block/bdev.c:1077
1 lock held by syz.3.1291/10144:
#0: ffffffff8d137640 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:4089
3 locks held by syz.5.1292/10140:
#0: ffff88805d7eb820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#0: ffff88805d7eb820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:658 [inline]
#0: ffff88805d7eb820 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1421
#1: ffff8880300d7130 (sk_lock-AF_CAN){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1780 [inline]
#1: ffff8880300d7130 (sk_lock-AF_CAN){+.+.}-{0:0}, at: bcm_release+0x217/0x930 net/can/bcm.c:1885
#2: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:324 [inline]
#2: ffffffff8d137778 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3da/0x880 kernel/rcu/tree_exp.h:1004
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a6/0x3e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf59/0xfa0 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 10147 Comm: syz.4.1290 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:memset_orig+0x19/0xac arch/x86/lib/memset_64.S:55
Code: f3 aa 4c 89 c8 c3 90 90 90 90 90 90 90 90 90 90 90 66 0f 1f 00 49 89 fa 40 0f b6 ce 48 b8 01 01 01 01 01 01 01 01 48 0f af c1 <41> 89 f9 41 83 e1 07 75 6c 48 89 d1 48 c1 e9 06 74 35 0f 1f 44 00
RSP: 0018:ffffc9000bf67110 EFLAGS: 00000206
RAX: 0000000000000000 RBX: ffffc9000bf67220 RCX: 0000000000000000
RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc9000bf67238
RBP: ffffc9000bf67238 R08: ffffc9000bf67247 R09: 1ffff920017ece48
R10: ffffc9000bf67238 R11: fffff520017ece49 R12: ffffc9000bf67ed0
R13: ffffc9000bf671e8 R14: ffffffff817420de R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000e78030 CR3: 00000000556ce000 CR4: 00000000003506f0
Call Trace:
unwind_next_frame+0x1628/0x2990 arch/x86/kernel/unwind_orc.c:592
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:46 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:53
kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x290 mm/slub.c:3852
pagetable_pte_dtor include/linux/mm.h:2998 [inline]
___pte_free_tlb+0x2d/0x130 arch/x86/mm/pgtable.c:55
__pte_free_tlb arch/x86/include/asm/pgalloc.h:61 [inline]
free_pte_range mm/memory.c:194 [inline]
free_pmd_range mm/memory.c:212 [inline]
free_pud_range mm/memory.c:246 [inline]
free_p4d_range mm/memory.c:280 [inline]
free_pgd_range+0x666/0xb30 mm/memory.c:360
free_pgtables+0x697/0x770 mm/memory.c:-1
exit_mmap+0x420/0xb90 mm/mmap.c:3313
__mmput+0x118/0x3a0 kernel/fork.c:1362
exit_mm+0x23f/0x340 kernel/exit.c:576
do_exit+0x909/0x2530 kernel/exit.c:877
do_group_exit+0x22d/0x2f0 kernel/exit.c:1032
get_signal+0x12a6/0x1390 kernel/signal.c:2911
arch_do_signal_or_restart+0xc2/0x7b0 arch/x86/kernel/signal.c:310
exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc314f9e0d9
Code: Unable to access opcode bytes at 0x7fc314f9e0af.
RSP: 002b:00007fc315daf028 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: 0000000000010106 RBX: 00007fc315226090 RCX: 00007fc314f9e0d9
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000005
RBP: 00007fc315035024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc315226128 R14: 00007fc315226090 R15: 00007ffcaaf430b8