INFO: task syz.3.75:6276 blocked for more than 143 seconds. Not tainted 6.16.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.75 state:D stack:29288 pid:6276 tgid:6274 ppid:5847 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x116a/0x5de0 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6879 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x6c7/0xb90 kernel/locking/mutex.c:747 blk_trace_remove kernel/trace/blktrace.c:406 [inline] blk_trace_ioctl+0x23a/0x280 kernel/trace/blktrace.c:745 blkdev_common_ioctl+0x176a/0x2480 block/ioctl.c:629 blkdev_ioctl+0x1cb/0x6d0 block/ioctl.c:698 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff29c98e929 RSP: 002b:00007ff29a7d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ff29cbb6080 RCX: 00007ff29c98e929 RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000003 RBP: 00007ff29ca10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007ff29cbb6080 R15: 00007ffd53bb33d8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e5c4c80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e5c4c80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e5c4c80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 4 locks held by kworker/u8:4/63: #0: ffff88801c6fe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000213fd10 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff8e5d0140 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3786 #3: ffff8880b843a418 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] #3: ffff8880b843a418 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 2 locks held by getty/5608: #0: ffff8880367720a0 (&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 6 locks held by syz.3.75/6275: 1 lock held by syz.3.75/6276: #0: ffff888026173a08 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:406 [inline] #0: ffff888026173a08 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x23a/0x280 kernel/trace/blktrace.c:745 2 locks held by syz.1.510/8358: 1 lock held by syz.2.525/8428: #0: ffff8880b843a418 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:614 [inline] #0: ffff8880b843a418 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:599 2 locks held by syz.2.525/8440: 2 locks held by syz.4.526/8430: #0: ffffffff9034e550 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:570 #1: ffffffff8e5d0278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:304 2 locks held by syz.1.528/8437: #0: ffffffff9034e550 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x286/0x5f0 net/core/net_namespace.c:570 #1: ffffffff8e5d0278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a3/0x3c0 kernel/rcu/tree_exp.h:336 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-syzkaller #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+0x5d7/0x6f0 arch/x86/kernel/process.c:148 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: 5835 Comm: syz-executor Not tainted 6.16.0-rc6-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:check_wait_context kernel/locking/lockdep.c:4858 [inline] RIP: 0010:__lock_acquire+0x241/0x1c90 kernel/locking/lockdep.c:5190 Code: ff 1f 00 00 48 0f a3 05 fd d4 3e 14 0f 83 1e 05 00 00 48 8d 04 80 48 8d 04 80 48 8d 04 c5 20 c9 d6 95 44 0f b6 b0 c4 00 00 00 <4c> 89 ef e8 77 b0 ff ff 44 0f b6 b8 c5 00 00 00 45 84 f6 0f 84 02 RSP: 0018:ffffc90003fa7af8 EFLAGS: 00000047 RAX: ffffffff95d6c920 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffff888078505a00 R08: 0000000000080000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: ffff8880785064f0 R13: ffff8880785064f0 R14: 0000000000000002 R15: ffffffff9af74070 FS: 000055557cd55500(0000) GS:ffff888124820000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f61d1f82178 CR3: 0000000070a16000 CR4: 00000000003526f0 Call Trace: lock_acquire kernel/locking/lockdep.c:5871 [inline] lock_acquire+0x179/0x350 kernel/locking/lockdep.c:5828 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 debug_object_free+0x13c/0x550 lib/debugobjects.c:962 destroy_hrtimer_on_stack kernel/time/hrtimer.c:455 [inline] hrtimer_nanosleep+0x187/0x380 kernel/time/hrtimer.c:2162 common_nsleep+0xa1/0xd0 kernel/time/posix-timers.c:1353 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1399 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1376 [inline] __x64_sys_clock_nanosleep+0x34d/0x4a0 kernel/time/posix-timers.c:1376 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x490 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f2e305c11a3 Code: 1f 84 00 00 00 00 00 83 ff 03 74 7b 83 ff 02 b8 fa ff ff ff 49 89 ca 0f 44 f8 80 3d 9e 53 1c 00 00 74 14 b8 e6 00 00 00 0f 05 d8 c3 66 2e 0f 1f 84 00 00 00 00 00 48 83 ec 28 48 89 54 24 10 RSP: 002b:00007fffc6c7b608 EFLAGS: 00000202 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2e305c11a3 RDX: 00007fffc6c7b620 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 000000000000ce30 R09: 00007f2e31390000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fffc6c7ba70 R13: 0000000000000004 R14: 00007fffc6c7b65c R15: 00007fffc6c7b6f0