INFO: task udevd:4363 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D
stack:23120 pid: 4363 ppid: 3560 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
io_schedule+0x7c/0xd0 kernel/sched/core.c:8503
wait_on_page_bit_common+0x83b/0xe50 mm/filemap.c:1356
wait_on_page_bit mm/filemap.c:1417 [inline]
wait_on_page_locked include/linux/pagemap.h:688 [inline]
wait_on_page_read mm/filemap.c:3437 [inline]
do_read_cache_page+0xb05/0x1030 mm/filemap.c:3480
read_mapping_page include/linux/pagemap.h:515 [inline]
read_part_sector+0xd4/0x4f0 block/partitions/core.c:726
adfspart_check_ICS+0xc3/0xe40 block/partitions/acorn.c:360
check_partition block/partitions/core.c:148 [inline]
blk_add_partitions block/partitions/core.c:611 [inline]
bdev_disk_changed+0x933/0x16c0 block/partitions/core.c:697
blkdev_get_whole+0x2f9/0x390 block/bdev.c:682
blkdev_get_by_dev+0x2d0/0xa60 block/bdev.c:827
blkdev_open+0x12d/0x2c0 block/fops.c:466
do_dentry_open+0x7ff/0xf80 fs/open.c:826
do_open fs/namei.c:3616 [inline]
path_openat+0x26f5/0x2fa0 fs/namei.c:3750
do_filp_open+0x1e2/0x410 fs/namei.c:3777
do_sys_openat2+0x150/0x4b0 fs/open.c:1255
do_sys_open fs/open.c:1271 [inline]
__do_sys_openat fs/open.c:1287 [inline]
__se_sys_openat fs/open.c:1282 [inline]
__x64_sys_openat+0x135/0x160 fs/open.c:1282
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0c23216407
RSP: 002b:00007ffeff313610 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f0c23128880 RCX: 00007f0c23216407
RDX: 00000000000a0800 RSI: 000055d0e00f6ca0 RDI: ffffffffffffff9c
RBP: 000055d0e00e3910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055d0e00f5b20
R13: 000055d0e00fb410 R14: 0000000000000000 R15: 000055d0e00f5b20
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31f360 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3946:
#0: ffff88802cc65098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
5 locks held by kworker/0:9/4273:
#0: ffff8881421c8d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000324fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffff88814813a220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#2: ffff88814813a220 (&dev->mutex){....}-{3:3}, at: hub_event+0x19f/0x55e0 drivers/usb/core/hub.c:5827
#3: ffff8880632c9220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#3: ffff8880632c9220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:974
#4: ffff8880632c81a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#4: ffff8880632c81a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x85/0x480 drivers/base/dd.c:974
4 locks held by udevd/4315:
#0: ffff888078847c30 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182
#1: ffff888063010888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x51/0x3c0 fs/kernfs/file.c:112
#2: ffff888059419748 (kn->active#32){++++}-{0:0}, at: kernfs_seq_start+0x71/0x3c0 fs/kernfs/file.c:113
#3: ffff8880632c9220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:809 [inline]
#3: ffff8880632c9220 (&dev->mutex){....}-{3:3}, at: uevent_show+0x17a/0x330 drivers/base/core.c:2408
3 locks held by kworker/u4:10/4333:
1 lock held by udevd/4363:
#0: ffff888020e72918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
2 locks held by syz-executor/5560:
#0: ffff8880204e2d18 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
#1: ffff8881473c2468 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0xaa/0xb90 drivers/block/loop.c:1366
3 locks held by kworker/1:16/5948:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000307fd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2:
ffffffff8c323cf0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043
1 lock held by udevd/7275:
#0: ffff88802057a118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x157/0xa60 block/bdev.c:820
2 locks held by syz.1.1581/10327:
#0: ffff88802057a118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xf9/0x7d0 block/bdev.c:915
#1: ffff888147177468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2071
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4315 Comm: udevd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:212 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:156 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:263 [inline]
RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:208
Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 7f 9a d0 02 66 2e 0f 1f 84 00 00 00 00 00
RSP: 0018:ffffc90000007e48 EFLAGS: 00000046
RAX: 000000000000a4c7 RBX: 000000000000a4c7 RCX: 0000000000000838
RDX: 0000000000000000 RSI: 000000000000a4c7 RDI: 0000000000000838
RBP: 0000000000000000 R08: ffffffff8d8a06ef R09: 1ffffffff1b140dd
R10: dffffc0000000000 R11: fffffbfff1b140de R12: dffffc0000000000
R13: 0000000010005fa1 R14: ffffffff8be359d8 R15: dffffc0000000000
FS: 00007f0c23128880(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5c15aaf001 CR3: 000000007a662000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
apic_write arch/x86/include/asm/apic.h:395 [inline]
lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:468
clockevents_program_event+0x1bc/0x310 kernel/time/clockevents.c:334
hrtimer_interrupt+0x4de/0x8d0 kernel/time/hrtimer.c:1824
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
__sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:check_kcov_mode kernel/kcov.c:174 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x2c/0x60 kernel/kcov.c:206
Code: 04 24 65 48 8b 0d c4 26 89 7e 65 8b 15 c5 26 89 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 34 16 00 00 00 74 2c <8b> 91 10 16 00 00 83 fa 02 75 21 48 8b 91 18 16 00 00 48 8b 32 48
RSP: 0018:ffffc9000343fd08 EFLAGS: 00000246
RAX: ffffffff81afe351 RBX: 0000000000000000 RCX: ffff888023b2d940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000687f90 R12: ffff8880232b7338
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
vma_compute_subtree_gap mm/mmap.c:322 [inline]
browse_rb mm/mmap.c:357 [inline]
validate_mm+0x4c1/0x950 mm/mmap.c:423
remove_vma_list mm/mmap.c:2631 [inline]
__do_munmap+0xcf3/0xdf0 mm/mmap.c:2902
__vm_munmap+0x140/0x240 mm/mmap.c:2952
__do_sys_munmap mm/mmap.c:2978 [inline]
__se_sys_munmap mm/mmap.c:2974 [inline]
__x64_sys_munmap+0x67/0x70 mm/mmap.c:2974
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f0c2328d097
Code: 73 01 c3 48 8b 0d 61 2d 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 31 2d 0d 00 f7 d8 64 89 01 48
RSP: 002b:00007ffeff30e308 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 000055d0e010b8e0 RCX: 00007f0c2328d097
RDX: 000055d0e010b928 RSI: 0000000000000200 RDI: 00007f0c227a9000
RBP: 0000000000000002 R08: 0000000000000030 R09: 000055d0e0103cd0
R10: 0000000000000000 R11: 0000000000000246 R12: 000055d0e0108520
R13: 00007f0c2396c39c R14: 0000000000000400 R15: 0000000000000009