INFO: task syz.2.1817:12797 blocked for more than 143 seconds. Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.1817 state:D stack:26920 pid:12797 tgid:12792 ppid:5832 task_flags:0x400740 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6878 schedule_timeout+0x257/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x2ff/0x4e0 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:504 [inline] do_coredump+0x8fa/0x4f10 fs/coredump.c:686 get_signal+0x22e3/0x26d0 kernel/signal.c:3019 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x84/0x110 kernel/entry/common.c:111 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x3f6/0x4c0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb5bd78e929 RSP: 002b:00007fb5bb4f60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007fb5bd9b6168 RCX: 00007fb5bd78e929 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fb5bd9b616c RBP: 00007fb5bd9b6160 R08: 00007fb5be5b3000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb5bd9b616c R13: 0000000000000000 R14: 00007ffd4e5deed0 R15: 00007ffd4e5defb8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4940 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 2 locks held by kworker/u8:4/64: 2 locks held by getty/5587: #0: ffff8880329e70a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 4 locks held by udevd/5835: #0: ffff888038569e80 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182 #1: ffff88805451c888 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff88805c5dc3c8 (kn->active#25){++++}-{0:0}, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff88805b9e4198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:889 [inline] #3: ffff88805b9e4198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 5 locks held by kworker/0:3/5884: #0: ffff888140acc948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900043a7d10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888029ecc198 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:884 [inline] , at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5894 #3: ffff88806141d198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #3: ffff88806141d198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004 #4: ffff88803762d160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #4: ffff88803762d160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004 5 locks held by kworker/1:4/5905: #0: ffff888140acc948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90002ee7d10 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff888144744198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #2: ffff888144744198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c0/0x4fa0 drivers/usb/core/hub.c:5894 #3: ffff88805b9e4198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #3: ffff88805b9e4198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004 #4: ffff88814cdba160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:884 [inline] #4: ffff88814cdba160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004 1 lock held by syz.4.2275/14518: #0: ffffffff8e5cfe00 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3786 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:470 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x5d4/0x6f0 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: 12793 Comm: syz.2.1817 Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:139 [inline] RIP: 0010:wrmsrq arch/x86/include/asm/msr.h:199 [inline] RIP: 0010:native_apic_msr_write arch/x86/include/asm/apic.h:212 [inline] RIP: 0010:native_apic_msr_write+0x28/0x40 arch/x86/include/asm/apic.h:206 Code: 90 90 f3 0f 1e fa 8d 87 30 ff ff ff 83 e0 ef 74 20 89 f8 83 e0 ef 83 f8 20 74 16 c1 ef 04 31 d2 89 f0 8d 8f 00 08 00 00 0f 30 <66> 90 c3 cc cc cc cc c3 cc cc cc cc 89 f6 31 d2 89 cf e9 11 71 a6 RSP: 0018:ffffc90000007ec0 EFLAGS: 00000046 RAX: 000000000000743a RBX: ffff8880b8423a00 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000000743a RDI: 0000000000000038 RBP: 000000000000743a R08: 0000000000000005 R09: 000000000000003f R10: 0000000000000020 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000020 R15: ffff8880b8427c80 FS: 00007fb5be5b26c0(0000) GS:ffff888124715000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b3000fff8 CR3: 0000000045fa4000 CR4: 00000000003526f0 Call Trace: apic_write arch/x86/include/asm/apic.h:405 [inline] lapic_next_event+0x10/0x20 arch/x86/kernel/apic/apic.c:416 clockevents_program_event+0x272/0x380 kernel/time/clockevents.c:334 tick_program_event+0xa9/0x140 kernel/time/tick-oneshot.c:44 hrtimer_interrupt+0x3e9/0x8e0 kernel/time/hrtimer.c:1900 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1039 [inline] __sysvec_apic_timer_interrupt+0x108/0x3f0 arch/x86/kernel/apic/apic.c:1056 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5875 Code: 33 38 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 32 f9 10 0f 0f 82 74 02 00 00 8b 35 1a 2b 11 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 c9 32 38 12 0f 85 c7 02 00 00 48 83 c4 RSP: 0018:ffffc90004f7faf0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: ffff88807a990418 RCX: ffffffff93e5a440 RDX: 0000000000000000 RSI: ffffffff8de0c23b RDI: ffffffff8c1588a0 RBP: 0000000000000000 R08: 8f0fa2758cfeaa68 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] io_cq_lock io_uring/io_uring.c:579 [inline] __io_cqring_overflow_flush+0x1ca/0x6f0 io_uring/io_uring.c:617 io_cqring_do_overflow_flush io_uring/io_uring.c:666 [inline] io_cqring_wait+0x14ed/0x18e0 io_uring/io_uring.c:2637 __do_sys_io_uring_enter+0xef8/0x1630 io_uring/io_uring.c:3444 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb5bd78e929 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:00007fb5be5b2038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007fb5bd9b5fa0 RCX: 00007fb5bd78e929 RDX: 000000000000235c RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007fb5bd810b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb5bd9b5fa0 R15: 00007ffd4e5defb8