INFO: task udevd:6784 blocked for more than 143 seconds.
Not tainted 6.15.0-syzkaller-07774-g90b83efa6701 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23272 pid:6784 tgid:6784 ppid:5198 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
__schedule_loop kernel/sched/core.c:6859 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6874
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
wait_for_reconnect drivers/block/nbd.c:1104 [inline]
nbd_handle_cmd drivers/block/nbd.c:1146 [inline]
nbd_queue_rq+0x662/0xf10 drivers/block/nbd.c:1204
blk_mq_dispatch_rq_list+0x4c0/0x1900 block/blk-mq.c:2118
__blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
__blk_mq_sched_dispatch_requests+0xda4/0x1570 block/blk-mq-sched.c:307
blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329
blk_mq_run_hw_queue+0x348/0x4f0 block/blk-mq.c:2356
blk_mq_dispatch_list+0xd0c/0xe00 include/linux/spinlock.h:-1
blk_mq_flush_plug_list+0x469/0x550 block/blk-mq.c:2965
__blk_flush_plug+0x3d3/0x4b0 block/blk-core.c:1220
blk_finish_plug block/blk-core.c:1247 [inline]
__submit_bio+0x2d3/0x5a0 block/blk-core.c:649
__submit_bio_noacct_mq block/blk-core.c:722 [inline]
submit_bio_noacct_nocheck+0x4ab/0xb50 block/blk-core.c:751
submit_bh fs/buffer.c:2836 [inline]
block_read_full_folio+0x7b7/0x830 fs/buffer.c:2468
filemap_read_folio+0x117/0x380 mm/filemap.c:2401
do_read_cache_folio+0x350/0x590 mm/filemap.c:3885
read_mapping_folio include/linux/pagemap.h:995 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:722
adfspart_check_ICS+0xa4/0xa50 block/partitions/acorn.c:360
check_partition block/partitions/core.c:141 [inline]
blk_add_partitions block/partitions/core.c:589 [inline]
bdev_disk_changed+0x75c/0x14b0 block/partitions/core.c:693
blkdev_get_whole+0x380/0x510 block/bdev.c:748
bdev_open+0x31e/0xd30 block/bdev.c:957
blkdev_open+0x3a8/0x510 block/fops.c:676
do_dentry_open+0xdf0/0x1970 fs/open.c:964
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:3887 [inline]
path_openat+0x2ee5/0x3830 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
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: 0033:0x7f37f92a7407
RSP: 002b:00007ffec5ca5340 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f37f995d880 RCX: 00007f37f92a7407
RDX: 00000000000a0800 RSI: 000055668f8eb550 RDI: ffffffffffffff9c
RBP: 000055668f8ea910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055668f902dd0
R13: 000055668f9023e0 R14: 0000000000000000 R15: 000055668f902dd0
INFO: task udevd:6925 blocked for more than 145 seconds.
Not tainted 6.15.0-syzkaller-07774-g90b83efa6701 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D stack:23272 pid:6925 tgid:6925 ppid:5198 task_flags:0x400140 flags:0x00004002
Call Trace:
context_switch kernel/sched/core.c:5392 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6781
__schedule_loop kernel/sched/core.c:6859 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6874
schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99
wait_for_reconnect drivers/block/nbd.c:1104 [inline]
nbd_handle_cmd drivers/block/nbd.c:1146 [inline]
nbd_queue_rq+0x662/0xf10 drivers/block/nbd.c:1204
blk_mq_dispatch_rq_list+0x4c0/0x1900 block/blk-mq.c:2118
__blk_mq_do_dispatch_sched block/blk-mq-sched.c:168 [inline]
blk_mq_do_dispatch_sched block/blk-mq-sched.c:182 [inline]
__blk_mq_sched_dispatch_requests+0xda4/0x1570 block/blk-mq-sched.c:307
blk_mq_sched_dispatch_requests+0xd7/0x190 block/blk-mq-sched.c:329
blk_mq_run_hw_queue+0x348/0x4f0 block/blk-mq.c:2356
blk_mq_dispatch_list+0xd0c/0xe00 include/linux/spinlock.h:-1
blk_mq_flush_plug_list+0x469/0x550 block/blk-mq.c:2965
__blk_flush_plug+0x3d3/0x4b0 block/blk-core.c:1220
blk_finish_plug block/blk-core.c:1247 [inline]
__submit_bio+0x2d3/0x5a0 block/blk-core.c:649
__submit_bio_noacct_mq block/blk-core.c:722 [inline]
submit_bio_noacct_nocheck+0x4ab/0xb50 block/blk-core.c:751
submit_bh fs/buffer.c:2836 [inline]
block_read_full_folio+0x7b7/0x830 fs/buffer.c:2468
filemap_read_folio+0x117/0x380 mm/filemap.c:2401
do_read_cache_folio+0x350/0x590 mm/filemap.c:3885
read_mapping_folio include/linux/pagemap.h:995 [inline]
read_part_sector+0xb6/0x2b0 block/partitions/core.c:722
adfspart_check_ICS+0xa4/0xa50 block/partitions/acorn.c:360
check_partition block/partitions/core.c:141 [inline]
blk_add_partitions block/partitions/core.c:589 [inline]
bdev_disk_changed+0x75c/0x14b0 block/partitions/core.c:693
blkdev_get_whole+0x380/0x510 block/bdev.c:748
bdev_open+0x31e/0xd30 block/bdev.c:957
blkdev_open+0x3a8/0x510 block/fops.c:676
do_dentry_open+0xdf0/0x1970 fs/open.c:964
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:3887 [inline]
path_openat+0x2ee5/0x3830 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
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: 0033:0x7f37f92a7407
RSP: 002b:00007ffec5ca5340 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f37f995d880 RCX: 00007f37f92a7407
RDX: 00000000000a0800 RSI: 000055668f8fba70 RDI: ffffffffffffff9c
RBP: 000055668f8ea910 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055668f913cc0
R13: 000055668f9023e0 R14: 0000000000000000 R15: 000055668f913cc0
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13ccc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
1 lock held by udevd/5198:
2 locks held by getty/5589:
#0: ffff88814c6be0a0 (&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 syz-execprog/6484:
#0: ffff8880b873b9d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
4 locks held by kworker/u9:4/6621:
#0: ffff888061508948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888061508948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc9000464fbc0 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000464fbc0 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88805179c078 (&hdev->lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x9b/0x8e0 net/bluetooth/hci_event.c:3713
#3: ffffffff8f672828 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2047 [inline]
#3: ffffffff8f672828 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x516/0x8e0 net/bluetooth/hci_event.c:3747
3 locks held by udevd/6784:
#0: ffff888025336358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
#1: ffff888025168590 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#1: ffff888025168590 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#1: ffff888025168590 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x31f/0x4f0 block/blk-mq.c:2356
#2: ffff8880258751f8 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xc8/0xf10 drivers/block/nbd.c:1196
3 locks held by udevd/6925:
#0: ffff888024d04358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
#1: ffff888021f98510 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#1: ffff888021f98510 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#1: ffff888021f98510 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x31f/0x4f0 block/blk-mq.c:2356
#2: ffff8880258ce178 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xc8/0xf10 drivers/block/nbd.c:1196
3 locks held by udevd/7541:
#0: ffff88802589a358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
#1: ffff888025168c10 (set->srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#1: ffff888025168c10 (set->srcu){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#1: ffff888025168c10 (set->srcu){.+.+}-{0:0}, at: blk_mq_run_hw_queue+0x31f/0x4f0 block/blk-mq.c:2356
#2: ffff8880259051f8 (&cmd->lock){+.+.}-{4:4}, at: nbd_queue_rq+0xc8/0xf10 drivers/block/nbd.c:1196
5 locks held by syz-executor/13386:
#0: ffff88805eb5cd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close net/bluetooth/hci_core.c:481 [inline]
#0: ffff88805eb5cd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_unregister_dev+0x1fe/0x500 net/bluetooth/hci_core.c:2678
#1: ffff88805eb5c078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x66a/0x1330 net/bluetooth/hci_sync.c:5213
#2: ffffffff8f672828 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2062 [inline]
#2: ffffffff8f672828 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xa1/0x230 net/bluetooth/hci_conn.c:2543
#3: ffff88806ec93b38 (&conn->lock#2){+.+.}-{4:4}, at: l2cap_conn_del+0x70/0x680 net/bluetooth/l2cap_core.c:1762
#4: ffffffff8e1427f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#4: ffffffff8e1427f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
2 locks held by syz-executor/14835:
1 lock held by syz-executor/16314:
2 locks held by syz-executor/19182:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-07774-g90b83efa6701 #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:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/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: 1208 Comm: kworker/0:2 Not tainted 6.15.0-syzkaller-07774-g90b83efa6701 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: rcu_gp process_srcu
RIP: 0010:find_stack lib/stackdepot.c:553 [inline]
RIP: 0010:stack_depot_save_flags+0x1aa/0x900 lib/stackdepot.c:619
Code: 00 31 f6 4c 89 54 24 18 e8 63 f8 ca ff 4c 8b 54 24 18 8b 74 24 04 85 db 75 62 4d 8b 24 24 4d 39 fc 74 56 41 39 6c 24 10 75 f0 <45> 39 54 24 14 75 e9 31 c0 49 8b 0c c6 49 3b 4c c4 20 75 dc 48 ff
RSP: 0018:ffffc90003cef5d8 EFLAGS: 00000046
RAX: ffff88823ae00000 RBX: 0000000000000000 RCX: 0000000000e82ae0
RDX: 00000000b4cb8fec RSI: 0000000000000000 RDI: 0000000031f042ad
RBP: 00000000451e82ae R08: 0000000037bb69ac R09: 000000006cdf6afb
R10: 000000000000000a R11: ffffffff81ac9920 R12: ffff888025286010
R13: 000000000000000a R14: ffffc90003cef650 R15: ffff88823bc82ae0
FS: 0000000000000000(0000) GS:ffff888125c66000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f38b636e0 CR3: 00000000517f2000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kasan_save_stack+0x4d/0x60 mm/kasan/common.c:48
kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548
insert_work+0x3d/0x330 kernel/workqueue.c:2183
__queue_work+0xcfc/0xfe0 kernel/workqueue.c:2341
queue_delayed_work_on+0x18b/0x280 kernel/workqueue.c:2561
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245