INFO: task syz.5.2468:16393 blocked for more than 143 seconds. Not tainted 6.15.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.2468 state:D stack:28344 pid:16393 tgid:16392 ppid:14092 task_flags:0x400040 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 device_lock include/linux/device.h:922 [inline] usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414 do_dentry_open+0xdf0/0x1970 fs/open.c:956 vfs_open+0x3b/0x340 fs/open.c:1086 do_open fs/namei.c:3880 [inline] path_openat+0x2ee5/0x3830 fs/namei.c:4039 do_filp_open+0x1fa/0x410 fs/namei.c:4066 do_sys_openat2+0x121/0x1c0 fs/open.c:1429 do_sys_open fs/open.c:1444 [inline] __do_sys_openat fs/open.c:1460 [inline] __se_sys_openat fs/open.c:1455 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1455 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8aad58d2d0 RSP: 002b:00007f8aae48eb70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f8aad58d2d0 RDX: 0000000000000002 RSI: 00007f8aae48ec10 RDI: 00000000ffffff9c RBP: 00007f8aae48ec10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f8aad7b5fa0 R15: 00007f8aad8dfa28 INFO: task syz.5.2468:16397 blocked for more than 144 seconds. Not tainted 6.15.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.2468 state:D stack:26296 pid:16397 tgid:16392 ppid:14092 task_flags:0x400640 flags:0x00024004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3d7/0x710 kernel/sched/completion.c:116 wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264 coredump_wait fs/coredump.c:419 [inline] do_coredump+0x7f8/0x2a30 fs/coredump.c:576 get_signal+0x10d9/0x1310 kernel/signal.c:3019 arch_do_signal_or_restart+0x95/0x780 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x8b/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8aad58e969 RSP: 002b:00007f8aae46e0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007f8aad7b6088 RCX: 00007f8aad58e969 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f8aad7b608c RBP: 00007f8aad7b6080 R08: 7fffffffffffffff R09: 0000000000000000 R10: 0000200000ffd000 R11: 0000000000000246 R12: 00007f8aad7b608c R13: 0000000000000000 R14: 00007f8aad8df940 R15: 00007f8aad8dfa28 Showing all locks held in the system: 3 locks held by ksoftirqd/1/23: #0: ffff8880b8839b58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:613 #1: ffff8880b8923b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987 #2: ffffffff99acaba0 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 ( rcu_read_lock ){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] ){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] ){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 6 locks held by kworker/1:1/47: 2 locks held by kworker/u8:6/1093: #0: ffff88801f6de948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801f6de948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc90003cbfc60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc90003cbfc60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 2 locks held by getty/5582: #0: ffff8880307970a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz.5.2468/16393: #0: ffff8880279a8198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #0: ffff8880279a8198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760 drivers/usb/core/devio.c:1054 2 locks held by syz.7.2914/18100: #0: ffff88807b4c8e08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff88807b4c8e08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff88807b4c8e08 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391 #1: ffffffff8df41338 (rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] , at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 2 locks held by dhcpcd/18120: #0: ffff888028dfc258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline] ffff888028dfc258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0 net/packet/af_packet.c:3252 #1: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] #1: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 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+0x4b/0x80 arch/x86/kernel/process.c:153 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: 5833 Comm: kworker/1:3 Not tainted 6.15.0-rc4-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Workqueue: events dvb_usb_read_remote_control RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:36 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:149 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:256 [inline] RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:212 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 cc cc cc cc cc f3 0f 1e fa 89 f6 31 d2 e9 72 0a 7e 03 66 RSP: 0018:ffffc90000a08e50 EFLAGS: 00000046 RAX: 000000000003d998 RBX: ffff8880b8923500 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000003d998 RDI: 0000000000000838 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000080000 R10: 0000000000000000 R11: ffffffff816f2250 R12: 00000000100053e2 R13: dffffc0000000000 R14: 000000000003d998 R15: 0000000000000020 FS: 0000000000000000(0000) GS:ffff8881261cc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055759f645028 CR3: 00000000684c2000 CR4: 00000000003526f0 DR0: 0000000080000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:405 [inline] lapic_next_event+0x11/0x20 arch/x86/kernel/apic/apic.c:415 clockevents_program_event+0x1cc/0x360 kernel/time/clockevents.c:334 hrtimer_interrupt+0x620/0xaa0 kernel/time/hrtimer.c:1900 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x108/0x410 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline] RIP: 0010:vprintk_emit+0x58f/0x7a0 kernel/printk/printk.c:2449 Code: 85 32 01 00 00 e8 41 f3 1e 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 30 f3 1e 00 eb 06 e8 29 f3 1e 00 fb 48 c7 c7 80 fa f2 8d <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 f9 3f RSP: 0018:ffffc90003fef8a0 EFLAGS: 00000293 RAX: ffffffff81a0cba7 RBX: ffffffff81a0ca64 RCX: ffff888060c9da00 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8df2fa80 RBP: ffffc90003fef9b0 R08: ffffffff8f7ec977 R09: 1ffffffff1efd92e R10: dffffc0000000000 R11: fffffbfff1efd92f R12: dffffc0000000000 R13: 1ffff920007fdf18 R14: 0000000000000200 R15: 0000000000000017 _printk+0xcf/0x120 kernel/printk/printk.c:2475 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_core_query+0x2c5/0x540 drivers/media/usb/dvb-usb/m920x.c:-1 dvb_usb_read_remote_control+0xb1/0x1a0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:261 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245