INFO: task syz-executor.2:4852 blocked for more than 143 seconds. Not tainted 5.18.0-rc6-syzkaller-00009-gfeb9c5e19e91 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.2 state:D stack:28408 pid: 4852 ppid: 3645 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5073 [inline] __schedule+0xa9a/0x4cc0 kernel/sched/core.c:6388 schedule+0xd2/0x1f0 kernel/sched/core.c:6460 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6519 __mutex_lock_common kernel/locking/mutex.c:673 [inline] __mutex_lock+0xa32/0x12f0 kernel/locking/mutex.c:733 misc_open+0x55/0x4a0 drivers/char/misc.c:107 chrdev_open+0x266/0x770 fs/char_dev.c:414 do_dentry_open+0x4a1/0x11e0 fs/open.c:824 do_open fs/namei.c:3476 [inline] path_openat+0x1c71/0x2910 fs/namei.c:3609 do_filp_open+0x1aa/0x400 fs/namei.c:3636 do_sys_openat2+0x16d/0x4c0 fs/open.c:1213 do_sys_open fs/open.c:1229 [inline] __do_sys_openat fs/open.c:1245 [inline] __se_sys_openat fs/open.c:1240 [inline] __x64_sys_openat+0x13f/0x1f0 fs/open.c:1240 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fcc0c2890e9 RSP: 002b:00007fcc0d383168 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fcc0c39bf60 RCX: 00007fcc0c2890e9 RDX: 0000000000105200 RSI: 0000000020000000 RDI: ffffffffffffff9c RBP: 00007fcc0c2e308d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fcc0c8cfb1f R14: 00007fcc0d383300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/28: #0: ffffffff8bd820e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6467 2 locks held by getty/3275: #0: ffff88801d742098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90002ce62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcea/0x1230 drivers/tty/n_tty.c:2075 6 locks held by kworker/1:6/3678: 2 locks held by kworker/u4:46/16623: #0: ffff8880b9d3a018 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:554 #1: ffff8880b9d27888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x3e7/0x4e0 kernel/sched/psi.c:889 2 locks held by syz-executor.1/4834: #0: ffffffff8c8166c8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x4a0 drivers/char/misc.c:107 #1: ffffffff8bc51c28 (system_transition_mutex){+.+.}-{3:3}, at: snapshot_open+0x3b/0x2a0 kernel/power/user.c:54 1 lock held by syz-executor.2/4852: #0: ffffffff8c8166c8 (misc_mtx){+.+.}-{3:3}, at: misc_open+0x55/0x4a0 drivers/char/misc.c:107 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 5.18.0-rc6-syzkaller-00009-gfeb9c5e19e91 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1e6/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:369 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3678 Comm: kworker/1:6 Not tainted 5.18.0-rc6-syzkaller-00009-gfeb9c5e19e91 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event RIP: 0010:io_serial_in+0x82/0xa0 drivers/tty/serial/8250/8250_port.c:461 Code: b4 da 1d fd 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 15 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c c3 e8 41 6b 69 fd eb a7 e8 6a 6b 69 fd eb e4 RSP: 0018:ffffc9000403e7d0 EFLAGS: 00000002 RAX: dffffc0000000000 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff845b65fc RDI: ffffffff9088a020 RBP: ffffffff90889fe0 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff845b65ed R11: 000000000000001f R12: 0000000000000000 R13: fffffbfff211144f R14: fffffbfff2111406 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000558d5577a000 CR3: 000000007e25d000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: serial_in drivers/tty/serial/8250/8250.h:115 [inline] wait_for_xmitr+0x9a/0x210 drivers/tty/serial/8250/8250_port.c:2089 serial8250_console_putchar+0x1d/0x60 drivers/tty/serial/8250/8250_port.c:3310 uart_console_write+0x59/0x100 drivers/tty/serial/serial_core.c:1935 serial8250_console_write+0xa57/0xc30 drivers/tty/serial/8250/8250_port.c:3382 call_console_drivers kernel/printk/printk.c:1952 [inline] console_unlock+0x9bc/0xdd0 kernel/printk/printk.c:2774 vprintk_emit+0x1b4/0x5f0 kernel/printk/printk.c:2272 dev_vprintk_emit+0x36e/0x3b2 drivers/base/core.c:4604 dev_printk_emit+0xba/0xf1 drivers/base/core.c:4615 __netdev_printk+0x1c6/0x27a net/core/dev.c:11113 netdev_warn+0xd7/0x109 net/core/dev.c:11166 asix_write_cmd.cold+0x3a/0x46 drivers/net/usb/asix_common.c:57 asix_set_sw_mii drivers/net/usb/asix_common.c:303 [inline] asix_check_host_enable+0x9e/0x1c0 drivers/net/usb/asix_common.c:77 __asix_mdio_read+0x93/0x220 drivers/net/usb/asix_common.c:503 asix_phy_reset+0x104/0x170 drivers/net/usb/asix_devices.c:215 ax88172_bind+0x437/0x5f0 drivers/net/usb/asix_devices.c:275 usbnet_probe+0xaf8/0x2580 drivers/net/usb/usbnet.c:1747 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:542 [inline] really_probe+0x23e/0xb20 drivers/base/dd.c:621 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:752 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:782 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:899 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427 __device_attach+0x228/0x4a0 drivers/base/dd.c:970 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487 device_add+0xb83/0x1e20 drivers/base/core.c:3405 usb_set_configuration+0x101e/0x1900 drivers/usb/core/message.c:2170 usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238 usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:542 [inline] really_probe+0x23e/0xb20 drivers/base/dd.c:621 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:752 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:782 __device_attach_driver+0x20b/0x2f0 drivers/base/dd.c:899 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:427 __device_attach+0x228/0x4a0 drivers/base/dd.c:970 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:487 device_add+0xb83/0x1e20 drivers/base/core.c:3405 usb_new_device.cold+0x641/0x1091 drivers/usb/core/hub.c:2566 hub_port_connect drivers/usb/core/hub.c:5363 [inline] hub_port_connect_change drivers/usb/core/hub.c:5507 [inline] port_event drivers/usb/core/hub.c:5665 [inline] hub_event+0x25c6/0x4680 drivers/usb/core/hub.c:5747 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 ---------------- Code disassembly (best guess): 0: b4 da mov $0xda,%ah 2: 1d fd 48 8d 7d sbb $0x7d8d48fd,%eax 7: 40 rex 8: 44 89 e1 mov %r12d,%ecx b: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 12: fc ff df 15: 48 89 fa mov %rdi,%rdx 18: d3 e3 shl %cl,%ebx 1a: 48 c1 ea 03 shr $0x3,%rdx 1e: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 22: 75 15 jne 0x39 24: 03 5d 40 add 0x40(%rbp),%ebx 27: 89 da mov %ebx,%edx 29: ec in (%dx),%al * 2a: 5b pop %rbx <-- trapping instruction 2b: 0f b6 c0 movzbl %al,%eax 2e: 5d pop %rbp 2f: 41 5c pop %r12 31: c3 retq 32: e8 41 6b 69 fd callq 0xfd696b78 37: eb a7 jmp 0xffffffe0 39: e8 6a 6b 69 fd callq 0xfd696ba8 3e: eb e4 jmp 0x24