INFO: task syz.0.1464:11305 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1464 state:D stack:27688 pid:11305 tgid:11299 ppid:5837 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 blk_debugfs_lock_nomemsave block/blk.h:740 [inline] blk_trace_startstop+0x8f/0x610 kernel/trace/blktrace.c:903 blk_trace_ioctl+0x314/0x920 kernel/trace/blktrace.c:949 blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724 blkdev_ioctl+0x528/0x740 block/ioctl.c:798 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc257b9c819 RSP: 002b:00007fc258a6d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc257e16270 RCX: 00007fc257b9c819 RDX: 0000000000000000 RSI: 0000000000001274 RDI: 0000000000000006 RBP: 00007fc257c32c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc257e16308 R14: 00007fc257e16270 R15: 00007fc257f3fa48 INFO: task syz.0.1464:11309 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.1464 state:D stack:28584 pid:11309 tgid:11299 ppid:5837 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5298 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6911 __schedule_loop kernel/sched/core.c:6993 [inline] schedule+0x164/0x360 kernel/sched/core.c:7008 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7065 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 blk_debugfs_lock_nomemsave block/blk.h:740 [inline] blk_trace_remove kernel/trace/blktrace.c:561 [inline] blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 blkdev_common_ioctl+0x13a7/0x3250 block/ioctl.c:724 blkdev_ioctl+0x528/0x740 block/ioctl.c:798 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc257b9c819 RSP: 002b:00007fc258a4c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc257e16360 RCX: 00007fc257b9c819 RDX: 0000000000000000 RSI: 0000000000001276 RDI: 0000000000000006 RBP: 00007fc257c32c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc257e163f8 R14: 00007fc257e16360 R15: 00007fc257f3fa48 Showing all locks held in the system: 1 lock held by ksoftirqd/1/23: #0: ffff8880b863ae60 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655 1 lock held by khungtaskd/30: #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 3 locks held by kworker/1:2/796: #0: ffff8880b863ae60 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655 #1: ffff8880b8724588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 #2: ffff888055014078 (&group->avgs_lock){+.+.}-{4:4}, at: psi_avgs_work+0x4d/0x160 kernel/sched/psi.c:588 2 locks held by getty/5583: #0: ffff8880373700a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 3 locks held by syz.0.1464/11304: 1 lock held by syz.0.1464/11305: #0: ffff888025ec1bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888025ec1bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_startstop+0x8f/0x610 kernel/trace/blktrace.c:903 1 lock held by syz.0.1464/11309: #0: ffff888025ec1bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:740 [inline] #0: ffff888025ec1bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove kernel/trace/blktrace.c:561 [inline] #0: ffff888025ec1bf0 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_ioctl+0x39a/0x920 kernel/trace/blktrace.c:952 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 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: 11045 Comm: kworker/u8:10 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:chacha_block_generic+0x227/0xc80 lib/crypto/chacha-block-generic.c:86 Code: 17 4c 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 ae 05 00 00 4c 89 e0 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 c1 05 00 00 41 89 2f <8b> 6c 24 18 4d 8d 7e 18 4c 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f RSP: 0018:ffffc9000c73f6c0 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffc9000c73f780 RCX: 000000006b58f9c7 RDX: dffffc0000000000 RSI: ffffc9000c73f6e4 RDI: ffffc9000c73f6ec RBP: 00000000f6931125 R08: 00000000e72263ca R09: ffffc9000c73f6e8 R10: 00000000f11b9083 R11: 0000000050edbe8a R12: ffffc9000c73f797 R13: ffffc9000c73f780 R14: ffffc9000c73f8c0 R15: ffffc9000c73f794 FS: 0000000000000000(0000) GS:ffff888125557000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5553fe7158 CR3: 000000000e54c000 CR4: 00000000003526f0 Call Trace: chacha20_block include/crypto/chacha.h:45 [inline] crng_fast_key_erasure+0x164/0x270 drivers/char/random.c:319 crng_make_state+0x1ce/0x600 drivers/char/random.c:385 _get_random_bytes+0xff/0x260 drivers/char/random.c:399 eth_random_addr include/linux/etherdevice.h:239 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:827 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline] nsim_dev_trap_report_work+0x38d/0xb80 drivers/net/netdevsim/dev.c:922 process_one_work kernel/workqueue.c:3276 [inline] process_scheduled_works+0xb6e/0x18c0 kernel/workqueue.c:3359 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3440 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245