INFO: task syz.1.856:10510 blocked for more than 144 seconds.
Not tainted 6.15.0-next-20250606-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.856 state:D stack:24136 pid:10510 tgid:10510 ppid:10114 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
bdev_release+0x1a9/0x650 block/bdev.c:1128
blkdev_release+0x15/0x20 block/fops.c:684
__fput+0x44c/0xa70 fs/file_table.c:467
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c0c38e929
RSP: 002b:00007ffdbf643598 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f8c0c5b7ba0 RCX: 00007f8c0c38e929
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f8c0c5b7ba0 R08: 0000000000000244 R09: 0000001ebf64388f
R10: 00007f8c0c5b7ac0 R11: 0000000000000246 R12: 000000000006aafb
R13: 00007f8c0c5b5fa0 R14: ffffffffffffffff R15: 00007ffdbf6436b0
INFO: task syz.1.856:10547 blocked for more than 144 seconds.
Not tainted 6.15.0-next-20250606-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.856 state:D stack:23208 pid:10547 tgid:10510 ppid:10114 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
io_schedule+0x80/0xd0 kernel/sched/core.c:7723
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:247
__wait_on_bit+0xb6/0x310 kernel/sched/wait_bit.c:49
out_of_line_wait_on_bit+0x123/0x170 kernel/sched/wait_bit.c:64
wait_on_bit_io include/linux/wait_bit.h:105 [inline]
__wait_on_buffer fs/buffer.c:123 [inline]
wait_on_buffer include/linux/buffer_head.h:422 [inline]
__bread_slow fs/buffer.c:1279 [inline]
__bread_gfp+0x2ca/0x3c0 fs/buffer.c:1524
sb_bread include/linux/buffer_head.h:348 [inline]
udf_read_tagged+0xad/0xe00 fs/udf/misc.c:199
udf_check_anchor_block+0x99/0x550 fs/udf/super.c:1903
udf_scan_anchors fs/udf/super.c:1943 [inline]
udf_load_vrs+0x6e3/0xf20 fs/udf/super.c:2024
udf_fill_super+0x5ad/0x17a0 fs/udf/super.c:2192
get_tree_bdev_flags+0x40b/0x4d0 fs/super.c:1679
vfs_get_tree+0x8f/0x2b0 fs/super.c:1802
do_new_mount+0x24a/0xa40 fs/namespace.c:3874
do_mount fs/namespace.c:4211 [inline]
__do_sys_mount fs/namespace.c:4422 [inline]
__se_sys_mount+0x317/0x410 fs/namespace.c:4399
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c0c38e929
RSP: 002b:00007f8c0d171038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f8c0c5b6080 RCX: 00007f8c0c38e929
RDX: 0000200000000080 RSI: 0000200000004a00 RDI: 0000200000000000
RBP: 00007f8c0c410b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000002008087 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8c0c5b6080 R15: 00007ffdbf643438
INFO: task syz.1.856:10548 blocked for more than 145 seconds.
Not tainted 6.15.0-next-20250606-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.856 state:D stack:26912 pid:10548 tgid:10510 ppid:10114 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
bdev_release+0x1a9/0x650 block/bdev.c:1128
blkdev_release+0x15/0x20 block/fops.c:684
__fput+0x44c/0xa70 fs/file_table.c:467
task_work_run+0x1d1/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c0c38e929
RSP: 002b:00007f8c0d150038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f8c0c5b6160 RCX: 00007f8c0c38e929
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 000000000000000a
RBP: 00007f8c0c410b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f8c0c5b6160 R15: 00007ffdbf643438
Showing all locks held in the system:
5 locks held by kworker/1:0/24:
#0: ffff8880206c4d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8880206c4d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900001e7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88804dfa5198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff88804dfa5198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a00 drivers/usb/core/hub.c:5863
#3: ffff88807aa5c510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3220 [inline]
#3: ffff88807aa5c510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x628/0x4a00 drivers/usb/core/hub.c:5916
#4: ffff88807e766098 (&hub->status_mutex){+.+.}-{4:4}, at: hub_ext_port_status+0x53/0x820 drivers/usb/core/hub.c:621
1 lock held by khungtaskd/31:
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5595:
#0: ffff88803072b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/5911:
#0: ffff8880252bb358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by syz-executor/10344:
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#0: ffffffff8e1448b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz.1.856/10510:
#0: ffff8880252bb358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1128
1 lock held by syz.1.856/10547:
#0: ffff88805a72e0e0 (&type->s_umount_key#87/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:345
1 lock held by syz.1.856/10548:
#0: ffff8880252bb358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1a9/0x650 block/bdev.c:1128
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-next-20250606-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 12924 Comm: syz.2.1276 Not tainted 6.15.0-next-20250606-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:tmigr_handle_remote+0x1312/0x13d0 kernel/time/timer_migration.c:1099
Code: 00 74 05 e8 60 fe 70 00 48 8b 7c 24 48 48 89 5f 58 e8 e2 73 b6 09 48 c7 84 24 e0 00 00 00 0e 36 e0 45 4b c7 04 2e 00 00 00 00 <66> 43 c7 44 2e 0a 00 00 43 c7 44 2e 13 00 00 00 00 43 c6 44 2e 17
RSP: 0018:ffffc90000007c40 EFLAGS: 00000202
RAX: 0000000000000101 RBX: 7fffffffffffffff RCX: 0000000000000100
RDX: 0000000000000002 RSI: ffffffff8d984053 RDI: 00000000ffffffff
RBP: ffffc90000007e30 R08: ffffffff8fa126f7 R09: 1ffffffff1f424de
R10: dffffc0000000000 R11: fffffbfff1f424df R12: 0000000000000000
R13: dffffc0000000000 R14: 1ffff92000000fa4 R15: ffff8880b8628518
FS: 00007fb77e1816c0(0000) GS:ffff888125c4d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb772c1f000 CR3: 0000000011416000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
handle_softirqs+0x286/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline]
RIP: 0010:vprintk_emit+0x58f/0x7a0 kernel/printk/printk.c:2449
Code: 85 32 01 00 00 e8 71 61 1f 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 60 61 1f 00 eb 06 e8 59 61 1f 00 fb 48 c7 c7 20 30 13 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 b9 36
RSP: 0018:ffffc9000b786d60 EFLAGS: 00000287
RAX: ffffffff81a0fd87 RBX: ffffffff81a0fc44 RCX: 0000000000080000
RDX: ffffc900120ac000 RSI: 000000000001ac68 RDI: ffffffff8e133020
RBP: ffffc9000b786e70 R08: ffffffff8fa126f7 R09: 1ffffffff1f424de
R10: dffffc0000000000 R11: fffffbfff1f424df R12: dffffc0000000000
R13: 1ffff920016f0db0 R14: 0000000000000200 R15: 000000000000002d
_printk+0xcf/0x120 kernel/printk/printk.c:2475
set_capacity_and_notify+0x208/0x2d0 block/genhd.c:93
loop_set_size+0x44/0xb0 drivers/block/loop.c:210
loop_configure+0xb34/0xfa0 drivers/block/loop.c:1068
lo_ioctl+0x79b/0x2410 drivers/block/loop.c:-1
blkdev_ioctl+0x5a5/0x6d0 block/ioctl.c:704
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb77d38e52b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007fb77e180dc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007fb77d38e52b
RDX: 0000000000000006 RSI: 0000000000004c00 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000363
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007fb77e180ef0 R14: 00007fb77e180eb0 R15: 00007fb772c00000