INFO: task udevd:779 blocked for more than 122 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:0 pid:779 tgid:779 ppid:109 flags:0x00000000
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x1528/0x1fb0 kernel/sched/core.c:7846
__schedule_loop kernel/sched/core.c:7927 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7942
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7999
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
bdev_open+0xd5/0xd60 block/bdev.c:926
blkdev_open+0x3d1/0x560 block/fops.c:627
do_dentry_open+0x978/0x1510 fs/open.c:960
vfs_open+0x86/0x240 fs/open.c:1092
do_open fs/namei.c:3782 [inline]
path_openat+0x2bb1/0x34f0 fs/namei.c:3941
do_filp_open+0x1f5/0x440 fs/namei.c:3968
do_sys_openat2+0x134/0x1d0 fs/open.c:1440
do_sys_open fs/open.c:1455 [inline]
__do_sys_openat fs/open.c:1471 [inline]
__se_sys_openat fs/open.c:1466 [inline]
__x64_sys_openat+0x13a/0x170 fs/open.c:1466
x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f564d1c9407
RSP: 002b:00007ffd019f8210 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f564d13d880 RCX: 00007f564d1c9407
RDX: 00000000000a0800 RSI: 000055c005023420 RDI: ffffffffffffff9c
RBP: 000055c004de32c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055c005025f70
R13: 000055c00502b280 R14: 0000000000000000 R15: 000055c005025f70
INFO: task syz-executor:2164 blocked for more than 123 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:0 pid:2164 tgid:2164 ppid:1 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x1528/0x1fb0 kernel/sched/core.c:7846
__schedule_loop kernel/sched/core.c:7927 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7942
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7999
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
bdev_open+0xd5/0xd60 block/bdev.c:926
blkdev_open+0x3d1/0x560 block/fops.c:627
do_dentry_open+0x978/0x1510 fs/open.c:960
vfs_open+0x86/0x240 fs/open.c:1092
do_open fs/namei.c:3782 [inline]
path_openat+0x2bb1/0x34f0 fs/namei.c:3941
do_filp_open+0x1f5/0x440 fs/namei.c:3968
do_sys_openat2+0x134/0x1d0 fs/open.c:1440
do_sys_open fs/open.c:1455 [inline]
__do_sys_openat fs/open.c:1471 [inline]
__se_sys_openat fs/open.c:1466 [inline]
__x64_sys_openat+0x13a/0x170 fs/open.c:1466
x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f89d8d55ed7
RSP: 002b:00007ffc614644c0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00005555575c4500 RCX: 00007f89d8d55ed7
RDX: 0000000000000002 RSI: 00007ffc614645f0 RDI: ffffffffffffff9c
RBP: 00007ffc6146459c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000050
R13: 000000000000005d R14: 0000000000029385 R15: 00007ffc614645f0
INFO: task syz.1.1033:3530 blocked for more than 123 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.1033 state:D stack:0 pid:3530 tgid:3529 ppid:288 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x1528/0x1fb0 kernel/sched/core.c:7846
__schedule_loop kernel/sched/core.c:7927 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7942
io_schedule+0x88/0xe0 kernel/sched/core.c:8756
folio_wait_bit_common+0x6d8/0x950 mm/filemap.c:1355
folio_put_wait_locked mm/filemap.c:1519 [inline]
do_read_cache_folio+0x14d/0x4c0 mm/filemap.c:4036
read_cache_folio+0x54/0x90 mm/filemap.c:4086
read_mapping_folio include/linux/pagemap.h:1021 [inline]
read_part_sector+0xcc/0x250 block/partitions/core.c:716
msdos_partition+0x116/0x2fd0 block/partitions/msdos.c:592
check_partition block/partitions/core.c:138 [inline]
blk_add_partitions block/partitions/core.c:583 [inline]
bdev_disk_changed+0x825/0x1610 block/partitions/core.c:687
loop_reread_partitions+0x64/0x110 drivers/block/loop.c:467
loop_configure+0x1068/0x13a0 drivers/block/loop.c:1078
lo_ioctl+0xa8b/0x2070 drivers/block/loop.c:1520
blkdev_ioctl+0x548/0x690 block/ioctl.c:699
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0x132/0x1b0 fs/ioctl.c:893
__x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:893
x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f8dd939acb9
RSP: 002b:00007f8dda266028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8dd9615fa0 RCX: 00007f8dd939acb9
RDX: 0000200000000280 RSI: 0000000000004c0a RDI: 0000000000000003
RBP: 00007f8dd9408bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8dd9616038 R14: 00007f8dd9615fa0 R15: 00007ffc6829bbc8
INFO: task syz.3.1034:3534 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1034 state:D stack:0 pid:3534 tgid:3533 ppid:291 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x1528/0x1fb0 kernel/sched/core.c:7846
__schedule_loop kernel/sched/core.c:7927 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7942
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7999
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
bdev_open+0xd5/0xd60 block/bdev.c:926
blkdev_open+0x3d1/0x560 block/fops.c:627
do_dentry_open+0x978/0x1510 fs/open.c:960
vfs_open+0x86/0x240 fs/open.c:1092
do_open fs/namei.c:3782 [inline]
path_openat+0x2bb1/0x34f0 fs/namei.c:3941
do_filp_open+0x1f5/0x440 fs/namei.c:3968
do_sys_openat2+0x134/0x1d0 fs/open.c:1440
do_sys_open fs/open.c:1455 [inline]
__do_sys_openat fs/open.c:1471 [inline]
__se_sys_openat fs/open.c:1466 [inline]
__x64_sys_openat+0x13a/0x170 fs/open.c:1466
x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7fa55635b58e
RSP: 002b:00007fa5572c1b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa5572c26c0 RCX: 00007fa55635b58e
RDX: 0000000000085822 RSI: 00007fa5572c1c00 RDI: ffffffffffffff9c
RBP: 00007fa5572c1c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007fa556616038 R14: 00007fa556615fa0 R15: 00007ffda2bf9908
INFO: task syz.0.1042:3552 blocked for more than 124 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1042 state:D stack:0 pid:3552 tgid:3551 ppid:290 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5996 [inline]
__schedule+0x1528/0x1fb0 kernel/sched/core.c:7846
__schedule_loop kernel/sched/core.c:7927 [inline]
schedule+0xc5/0x240 kernel/sched/core.c:7942
schedule_preempt_disabled+0x14/0x30 kernel/sched/core.c:7999
__mutex_lock_common kernel/locking/mutex.c:707 [inline]
__mutex_lock+0x960/0x1bb0 kernel/locking/mutex.c:803
__mutex_lock_slowpath+0xe/0x20 kernel/locking/mutex.c:1134
mutex_lock+0x113/0x1d0 kernel/locking/mutex.c:285
bdev_open+0xd5/0xd60 block/bdev.c:926
blkdev_open+0x3d1/0x560 block/fops.c:627
do_dentry_open+0x978/0x1510 fs/open.c:960
vfs_open+0x86/0x240 fs/open.c:1092
do_open fs/namei.c:3782 [inline]
path_openat+0x2bb1/0x34f0 fs/namei.c:3941
do_filp_open+0x1f5/0x440 fs/namei.c:3968
do_sys_openat2+0x134/0x1d0 fs/open.c:1440
do_sys_open fs/open.c:1455 [inline]
__do_sys_openat fs/open.c:1471 [inline]
__se_sys_openat fs/open.c:1466 [inline]
__x64_sys_openat+0x13a/0x170 fs/open.c:1466
x64_sys_call+0xe69/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f2b6095b58e
RSP: 002b:00007f2b5f3f6b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f2b5f3f76c0 RCX: 00007f2b6095b58e
RDX: 0000000000085822 RSI: 00007f2b5f3f6c00 RDI: ffffffffffffff9c
RBP: 00007f2b5f3f6c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007f2b60c16038 R14: 00007f2b60c15fa0 R15: 00007ffc996456f8
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 bfede744b46277b76d69ebe6cb8c22209d769bcb
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
dump_stack+0x19/0x20 lib/dump_stack.c:129
nmi_cpu_backtrace+0x2ba/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x142/0x2c0 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:41
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:267 [inline]
watchdog+0xdad/0xf00 kernel/hung_task.c:423
kthread+0x2c9/0x370 kernel/kthread.c:389
ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 380 Comm: kworker/0:4 Not tainted syzkaller #0 bfede744b46277b76d69ebe6cb8c22209d769bcb
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_out+0x85/0xd0 drivers/tty/serial/8250/8250_port.c:413
Code: fe 44 89 e1 41 d3 e6 49 83 c7 08 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 ff e8 44 cf bc fe 45 03 37 89 d8 44 89 f2 ee <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 44 89 e1 80 e1 07
RSP: 0018:ffffc9000db1f008 EFLAGS: 00000002
RAX: 0000000000000031 RBX: 0000000000000031 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 000000000001b1d4 RDI: 000000000001b1d5
RBP: ffffc9000db1f030 R08: ffff8881056fc107 R09: 1ffff11020adf820
R10: 0000000000000000 R11: ffffffff83227a70 R12: 0000000000000000
R13: dffffc0000000000 R14: 00000000000003f8 R15: ffffffff88c0c4e8
FS: 0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6a375e0ad8 CR3: 000000012fcc6000 CR4: 00000000003526b0
Call Trace:
serial_out drivers/tty/serial/8250/8250.h:142 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:-1 [inline]
serial8250_console_write+0x16d6/0x21a0 drivers/tty/serial/8250/8250_port.c:3421
univ8250_console_write+0x6f/0xb0 drivers/tty/serial/8250/8250_core.c:396
console_emit_next_record kernel/printk/printk.c:3151 [inline]
console_flush_all+0x5fa/0xac0 kernel/printk/printk.c:3239
__console_flush_and_unlock kernel/printk/printk.c:3298 [inline]
console_unlock+0xf8/0x2c0 kernel/printk/printk.c:3338
vprintk_emit+0x282/0x650 kernel/printk/printk.c:2462
dev_vprintk_emit+0x359/0x420 drivers/base/core.c:4962
dev_printk_emit+0xef/0x150 drivers/base/core.c:4973
__dev_printk+0x17f/0x1b0 drivers/base/core.c:4985
_dev_err+0x11f/0x180 drivers/base/core.c:5028
hub_port_init+0x1467/0x2840 drivers/usb/core/hub.c:-1
hub_port_connect drivers/usb/core/hub.c:5503 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5714 [inline]
port_event drivers/usb/core/hub.c:5878 [inline]
hub_event+0x2676/0x4700 drivers/usb/core/hub.c:5960
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0x7d4/0x1020 kernel/workqueue.c:3319
worker_thread+0xc70/0x10b0 kernel/workqueue.c:3400
kthread+0x2c9/0x370 kernel/kthread.c:389
ret_from_fork+0x64/0xa0 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244