INFO: task syz.4.931:8999 blocked for more than 144 seconds. Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.931 state:D stack:27120 pid:8999 tgid:8997 ppid:5818 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6913 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x6bd/0xb10 kernel/locking/mutex.c:730 sync_bdevs+0xfd/0x360 block/bdev.c:1246 ksys_sync+0xb3/0x150 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:113 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe6bf58cda9 RSP: 002b:00007fe6bd3f6038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007fe6bf7a6080 RCX: 00007fe6bf58cda9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fe6bf7a6080 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe6bf7a6080 R15: 00007ffea2e0d2b8 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6746 6 locks held by kworker/0:2/117: #0: ffff888021ea8948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90002de7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff888028eb4190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff888028eb4190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c1/0x4e10 drivers/usb/core/hub.c:5851 #3: ffff888028eb7510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3208 [inline] #3: ffff888028eb7510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5420 [inline] #3: ffff888028eb7510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5663 [inline] #3: ffff888028eb7510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5823 [inline] #3: ffff888028eb7510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x27ec/0x4e10 drivers/usb/core/hub.c:5905 #4: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #4: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #4: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2370 [inline] #4: ffffffff8e1be000 (rcu_read_lock){....}-{1:3}, at: bpf_trace_run4+0x1d6/0x5a0 kernel/trace/bpf_trace.c:2414 #5: ffffffff8e0cb320 (console_owner){-.-.}-{0:0}, at: console_lock_spinning_enable+0x9f/0xd0 kernel/printk/printk.c:1924 2 locks held by getty/5572: #0: ffff888031e5b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 1 lock held by udevd/5807: #0: ffff8880622ae4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe20 block/bdev.c:903 4 locks held by udevd/5821: #0: ffff888055945668 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xd8/0x12b0 fs/seq_file.c:182 #1: ffff88803625bc88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888034c64788 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888063214190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff888063214190 (&dev->mutex){....}-{4:4}, at: uevent_show+0x188/0x3b0 drivers/base/core.c:2729 6 locks held by kworker/1:7/5900: #0: ffff888021ea8948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3211 #1: ffffc90003ac7d18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3212 #2: ffff888028f54190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff888028f54190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c1/0x4e10 drivers/usb/core/hub.c:5851 #3: ffff888063214190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #3: ffff888063214190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #4: ffff8880638a7160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff8880638a7160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1005 #5: ffffffff8e073e10 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xaa/0x250 kernel/umh.c:214 1 lock held by syz.4.931/8999: #0: ffff8880622ae4c8 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0xfd/0x360 block/bdev.c:1246 1 lock held by syz.2.1433/10766: ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 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:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0xf62/0x12b0 kernel/hung_task.c:399 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 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: 10766 Comm: syz.2.1433 Not tainted 6.13.0-syzkaller-08265-g9c5968db9e62 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:__might_sleep+0x33/0x170 kernel/sched/core.c:8683 Code: 00 00 fc ff df 41 54 65 4c 8b 25 08 e0 7b 7e 55 89 f5 53 48 89 fb 49 8d 7c 24 18 48 83 ec 10 48 89 fa 48 c1 ea 03 0f b6 14 02 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 d8 00 00 00 41 RSP: 0018:ffffc900039e76a0 EFLAGS: 00000a02 RAX: dffffc0000000000 RBX: ffffffff8b6cc2e0 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000232 RDI: ffff8880310ac898 RBP: 0000000000000232 R08: ffffffff89fadf57 R09: 0000000000000000 R10: ffffc900039e7830 R11: 0000000000000000 R12: ffff8880310ac880 R13: 0000000000000002 R14: 0000000000000000 R15: ffffc900039e7750 FS: 00007fbd2d6026c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000203a4030 CR3: 0000000033a78000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __mutex_lock_common kernel/locking/mutex.c:562 [inline] __mutex_lock+0x108/0xb10 kernel/locking/mutex.c:730 __unix_dgram_recvmsg+0x267/0xe50 net/unix/af_unix.c:2426 unix_dgram_recvmsg+0xd0/0x110 net/unix/af_unix.c:2531 sock_recvmsg_nosec net/socket.c:1018 [inline] ____sys_recvmsg+0x5f8/0x6b0 net/socket.c:2786 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2830 do_recvmmsg+0x2f8/0x740 net/socket.c:2925 __sys_recvmmsg net/socket.c:2999 [inline] __do_sys_recvmmsg net/socket.c:3022 [inline] __se_sys_recvmmsg net/socket.c:3015 [inline] __x64_sys_recvmmsg+0x239/0x290 net/socket.c:3015 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbd2c78cda9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fbd2d602038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007fbd2c9a6080 RCX: 00007fbd2c78cda9 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 00007fbd2c80e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fbd2c9a6080 R15: 00007ffe06a422b8