INFO: task syz-executor.4:6275 blocked for more than 143 seconds. Not tainted 6.7.0-rc2-next-20231124-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:29536 pid:6275 tgid:6265 ppid:29841 flags:0x00000006 Call Trace: context_switch kernel/sched/core.c:5399 [inline] __schedule+0xf15/0x5c00 kernel/sched/core.c:6726 __schedule_loop kernel/sched/core.c:6801 [inline] schedule+0xe7/0x270 kernel/sched/core.c:6816 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6873 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x5b4/0x9c0 kernel/locking/mutex.c:747 blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 blkdev_common_ioctl+0x1575/0x1ce0 block/ioctl.c:562 blkdev_ioctl+0x249/0x770 block/ioctl.c:627 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x40/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x62/0x6a RIP: 0033:0x7f120467cae9 RSP: 002b:00007f12053020c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f120479c120 RCX: 00007f120467cae9 RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000005 RBP: 00007f12046c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f120479c120 R15: 00007ffca4ca54a8 Showing all locks held in the system: 1 lock held by pool_workqueue_/3: 1 lock held by khungtaskd/29: #0: ffffffff8cfacf60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:301 [inline] #0: ffffffff8cfacf60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:747 [inline] #0: ffffffff8cfacf60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613 2 locks held by getty/4815: #0: ffff8880276010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900015d72f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc4/0x1490 drivers/tty/n_tty.c:2201 2 locks held by kworker/0:8/5171: #0: ffff888013076938 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78c/0x15f0 kernel/workqueue.c:2608 #1: ffffc90004cbfd80 ((work_completion)(&rew->rew_work)){+.+.}-{0:0}, at: process_one_work+0x7f6/0x15f0 kernel/workqueue.c:2609 2 locks held by kworker/u4:14/5482: 3 locks held by kworker/1:2/20046: #0: ffff888013074d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78c/0x15f0 kernel/workqueue.c:2608 #1: ffffc90004397d80 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7f6/0x15f0 kernel/workqueue.c:2609 #2: ffff8880b99297d8 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x5d/0x200 kernel/time/timer.c:999 1 lock held by syz-executor.4/6275: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.5/6276: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.3/6324: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.3/6325: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.0/6328: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.0/6332: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.2/6333: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.4/6388: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.4/6389: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.1/6396: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.5/6399: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.5/6400: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.3/6444: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.3/6445: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.0/6457: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.0/6458: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.2/6467: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 1 lock held by syz-executor.2/6468: #0: ffff8881437f21f0 (&q->debugfs_mutex){+.+.}-{3:3}, at: blk_trace_ioctl+0xc9/0x290 kernel/trace/blktrace.c:736 6 locks held by syz-executor.5/6487: #0: ffff888051042420 (sb_writers#10){.+.+}-{0:0}, at: ksys_write+0x12f/0x250 fs/read_write.c:637 #1: ffff88817583a088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x27d/0x500 fs/kernfs/file.c:325 #2: ffffffff8cff8668 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:368 [inline] #2: ffffffff8cff8668 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0x136/0x570 kernel/cgroup/cgroup.c:1662 #3: ffffffff8ce51e70 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2413 [inline] #3: ffffffff8ce51e70 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x18f/0x660 kernel/cgroup/cgroup.c:2917 #4: ffffffff8cff8430 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2415 [inline] #4: ffffffff8cff8430 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2411 [inline] #4: ffffffff8cff8430 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x19b/0x660 kernel/cgroup/cgroup.c:2917 #5: ffffffff8cfb8938 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline] #5: ffffffff8cfb8938 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3ff/0x800 kernel/rcu/tree_exp.h:996 2 locks held by syz-executor.1/6561: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.7.0-rc2-next-20231124-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 nmi_cpu_backtrace+0x277/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline] watchdog+0xf86/0x1210 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+0x11/0x20 arch/x86/entry/entry_64.S:242 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:112