INFO: task syz.2.6783:32592 blocked for more than 143 seconds. Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.6783 state:D stack:28992 pid:32592 tgid:32564 ppid:28488 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0xcda/0x2f80 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6621 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6678 __mutex_lock_common kernel/locking/mutex.c:684 [inline] __mutex_lock+0x5b8/0x9c0 kernel/locking/mutex.c:752 yurex_write+0x17f/0x940 drivers/usb/misc/yurex.c:447 vfs_write+0x29a/0x1140 fs/read_write.c:588 ksys_write+0x12f/0x260 fs/read_write.c:643 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: 0033:0x7fdf0cf5def9 RSP: 002b:00007fdf0bb8f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fdf0d116130 RCX: 00007fdf0cf5def9 RDX: 0000000000000001 RSI: 0000000020000000 RDI: 0000000000000005 RBP: 00007fdf0cfd0b76 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007fdf0d116130 R15: 00007ffe84cb2758 Showing all locks held in the system: 1 lock held by rcu_preempt/16: #0: ffff8881f593d718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:560 [inline] #0: ffff8881f593d718 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1415 [inline] #0: ffff8881f593d718 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1714 [inline] #0: ffff8881f593d718 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x28e/0x2f80 kernel/sched/core.c:6436 1 lock held by khungtaskd/30: #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff88ebb660 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6626 3 locks held by kworker/1:2/806: #0: ffff888105ebad48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc90001bcfd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffff888109736190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #2: ffff888109736190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 2 locks held by getty/2605: #0: ffff888106bf70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000432f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc8/0x1490 drivers/tty/n_tty.c:2211 5 locks held by kworker/1:3/13827: #0: ffff888105ebad48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc9000fa77d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffff8881097cd190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #2: ffff8881097cd190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff88811b80a190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff88811b80a190 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1004 #4: ffff88811baf0160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff88811baf0160 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7f/0x4b0 drivers/base/dd.c:1004 5 locks held by kworker/1:0/22439: #0: ffff888105ebad48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1277/0x1b40 kernel/workqueue.c:3206 #1: ffffc9000737fd80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1b40 kernel/workqueue.c:3207 #2: ffff8881097b5190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #2: ffff8881097b5190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1be/0x4f40 drivers/usb/core/hub.c:5849 #3: ffff888132605190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #3: ffff888132605190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2295 #4: ffff8881196b0160 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1009 [inline] #4: ffff8881196b0160 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1094 [inline] #4: ffff8881196b0160 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1292 6 locks held by kworker/0:0/26247: 1 lock held by syz.2.6783/32590: 1 lock held by syz.2.6783/32592: #0: ffff88812b40dcb0 (&dev->io_mutex){+.+.}-{3:3}, at: yurex_write+0x17f/0x940 drivers/usb/misc/yurex.c:447 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119 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:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 2536 Comm: klogd Not tainted 6.11.0-rc7-syzkaller-00152-g68d4209158f4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:206 [inline] RIP: 0010:unwind_next_frame+0x1d6/0x23a0 arch/x86/kernel/unwind_orc.c:494 Code: 0f 84 c9 02 00 00 e8 b9 33 3f 00 31 ff 4c 89 e6 e8 1f 36 3f 00 4d 85 e4 0f 84 ee 0a 00 00 e8 a1 33 3f 00 48 c7 c6 00 00 00 81 <4c> 89 e7 e8 42 35 3f 00 49 81 fc 00 00 00 81 0f 82 9e 02 00 00 e8 RSP: 0018:ffffc9000170f498 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffffc9000170f518 RCX: ffffffff81155fe1 RDX: ffff8881157dba80 RSI: ffffffff81000000 RDI: 0000000000000007 RBP: 0000000000000001 R08: 0000000000000007 R09: 0000000000000000 R10: ffffffff81aa9b72 R11: 0000000000000000 R12: ffffffff81aa9b72 R13: 0000000000000000 R14: ffffc9000170f5d8 R15: ffffc9000170f54d FS: 00007f19fad5f380(0000) GS:ffff8881f5900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f92c07befe0 CR3: 00000001158ea000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x100/0x170 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:370 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:387 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slub.c:4162 [inline] __kmalloc_node_track_caller_noprof+0x1ff/0x3e0 mm/slub.c:4181 kmalloc_reserve+0xef/0x2c0 net/core/skbuff.c:605 __alloc_skb+0x164/0x380 net/core/skbuff.c:674 alloc_skb include/linux/skbuff.h:1320 [inline] alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6526 sock_alloc_send_pskb+0x7f1/0x980 net/core/sock.c:2815 unix_dgram_sendmsg+0x467/0x1920 net/unix/af_unix.c:2030 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x47f/0x4e0 net/socket.c:2204 __do_sys_sendto net/socket.c:2216 [inline] __se_sys_sendto net/socket.c:2212 [inline] __x64_sys_sendto+0xe0/0x1c0 net/socket.c:2212 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: 0033:0x7f19faec19b5 Code: 8b 44 24 08 48 83 c4 28 48 98 c3 48 98 c3 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 26 45 31 c9 45 31 c0 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 7a 48 8b 15 44 c4 0c 00 f7 d8 64 89 02 48 83 RSP: 002b:00007fff90a2f958 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f19faec19b5 RDX: 000000000000004c RSI: 000055a2d3b7db40 RDI: 0000000000000003 RBP: 000055a2d3b702c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000013 R13: 00007f19fb04f212 R14: 00007fff90a2fa58 R15: 0000000000000000