INFO: task syz.0.1766:12738 blocked for more than 143 seconds.
Not tainted 6.15.0-syzkaller-10401-gdee264c16a63 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1766 state:D stack:27464 pid:12738 tgid:12736 ppid:5812 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6781
__schedule_loop kernel/sched/core.c:6859 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6874
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6931
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:746
nbd_start_device_ioctl drivers/block/nbd.c:1542 [inline]
__nbd_ioctl drivers/block/nbd.c:1602 [inline]
nbd_ioctl+0x30a/0xda0 drivers/block/nbd.c:1642
blkdev_ioctl+0x277/0x6d0 block/ioctl.c:704
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl fs/ioctl.c:893 [inline]
__x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:893
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa77378e969
RSP: 002b:00007fa7715f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa7739b5fa0 RCX: 00007fa77378e969
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000003
RBP: 00007fa773810ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa7739b5fa0 R15: 00007fff3fa151f8
INFO: task syz.0.1766:12741 blocked for more than 144 seconds.
Not tainted 6.15.0-syzkaller-10401-gdee264c16a63 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1766 state:D stack:27784 pid:12741 tgid:12736 ppid:5812 task_flags:0x480140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x116a/0x5de0 kernel/sched/core.c:6781
__schedule_loop kernel/sched/core.c:6859 [inline]
schedule+0xe7/0x3a0 kernel/sched/core.c:6874
blk_mq_freeze_queue_wait+0x143/0x1b0 block/blk-mq.c:190
blk_mq_freeze_queue include/linux/blk-mq.h:934 [inline]
queue_limits_commit_update_frozen+0x93/0x110 block/blk-settings.c:482
nbd_set_size+0x4e7/0x730 drivers/block/nbd.c:374
__nbd_ioctl drivers/block/nbd.c:1593 [inline]
nbd_ioctl+0xd34/0xda0 drivers/block/nbd.c:1642
blkdev_ioctl+0x277/0x6d0 block/ioctl.c:704
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl fs/ioctl.c:893 [inline]
__x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:893
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa77378e969
RSP: 002b:00007fa7715d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fa7739b6080 RCX: 00007fa77378e969
RDX: 0000000000000582 RSI: 000000000000ab07 RDI: 0000000000000003
RBP: 00007fa7715d5090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000001 R14: 00007fa7739b6080 R15: 00007fff3fa151f8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770
2 locks held by getty/5575:
#0: ffff88814ca0b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fee2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
1 lock held by udevd/5815:
#0: ffff888143338358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:945
2 locks held by kworker/u8:14/5992:
3 locks held by udevd/6732:
#0: ffff8880b843bd18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline]
#0: ffff8880b843bd18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599
#1: ffff8880b8524048 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2c1/0x8e0 kernel/sched/psi.c:987
#2: ffff888079c9c958 (&ep->lock){....}-{3:3}, at: ep_poll_callback+0xcf/0xc70 fs/eventpoll.c:1347
8 locks held by kworker/0:0/12502:
#0: ffff888022aa6d48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
#1: ffffc9001bba7d10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
#2: ffff888144b06198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#2: ffff888144b06198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5859
#3: ffff8880554cd198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline]
#3: ffff8880554cd198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004
#4: ffff888144b10098 (&hub->status_mutex){+.+.}-{4:4}, at: hub_ext_port_status+0x5e/0x670 drivers/usb/core/hub.c:621
#5: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#5: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#5: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
#5: ffffffff8e5c4780 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xbd/0x20a0 arch/x86/kernel/unwind_orc.c:479
#6: ffffffff9aff11b0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x135/0x3a0 lib/debugobjects.c:873
#7: ffff8880b843b498 (&pool->lock){-.-.}-{2:2}, at: __queue_work+0x26b/0x10f0 kernel/workqueue.c:2301
1 lock held by syz.0.1766/12738:
#0: ffff888026937a30 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_start_device_ioctl drivers/block/nbd.c:1542 [inline]
#0: ffff888026937a30 (&nbd->config_lock){+.+.}-{4:4}, at: __nbd_ioctl drivers/block/nbd.c:1602 [inline]
#0: ffff888026937a30 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x30a/0xda0 drivers/block/nbd.c:1642
4 locks held by syz.0.1766/12741:
#0: ffff888026937a30 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x150/0xda0 drivers/block/nbd.c:1635
#1: ffff888142fc41b0 (&q->limits_lock){+.+.}-{4:4}, at: queue_limits_start_update include/linux/blkdev.h:1002 [inline]
#1: ffff888142fc41b0 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x2c3/0x730 drivers/block/nbd.c:354
#2: ffff888142fc3b58 (&q->q_usage_counter(io)#49){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:205
#3: ffff888142fc3b90 (&q->q_usage_counter(queue)){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x15/0x20 block/blk-mq.c:205
1 lock held by syz.5.1889/13246:
#0: ffff888143338358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0xfd/0x360 block/bdev.c:1288
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-10401-gdee264c16a63 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xf70/0x12c0 kernel/hung_task.c:437
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.15.0-syzkaller-10401-gdee264c16a63 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:82
Code: e3 74 02 e9 53 fb 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d b3 90 2d 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffc90000197df8 EFLAGS: 000002c6
RAX: 0000000004a3380b RBX: 0000000000000001 RCX: ffffffff8b7c7449
RDX: 0000000000000000 RSI: ffffffff8de06e85 RDI: ffffffff8c1532c0
RBP: ffffed1003cde488 R08: 0000000000000001 R09: ffffed10170a663d
R10: ffff8880b85331eb R11: 0000000000000001 R12: 0000000000000001
R13: ffff88801e6f2440 R14: ffffffff90a78850 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88812486e000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1ce1fbcd58 CR3: 000000007c147000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
arch_safe_halt arch/x86/include/asm/paravirt.h:107 [inline]
default_idle+0x13/0x20 arch/x86/kernel/process.c:743
default_idle_call+0x6d/0xb0 kernel/sched/idle.c:117
cpuidle_idle_call kernel/sched/idle.c:185 [inline]
do_idle+0x391/0x510 kernel/sched/idle.c:325
cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:423
start_secondary+0x21d/0x2b0 arch/x86/kernel/smpboot.c:315
common_startup_64+0x13e/0x148