INFO: task syz.4.5013:23033 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.4.5013 state:D stack:28760 pid:23033 tgid:23023 ppid:21404 task_flags:0x400040 flags:0x08080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1821/0x5740 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x164/0x360 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0x7f7/0x1550 kernel/locking/mutex.c:820 blk_debugfs_lock_nomemsave block/blk.h:758 [inline] blk_trace_remove+0x20/0x40 kernel/trace/blktrace.c:561 sg_ioctl_common drivers/scsi/sg.c:1124 [inline] sg_ioctl+0x45b/0x2220 drivers/scsi/sg.c:1158 __do_compat_sys_ioctl fs/ioctl.c:695 [inline] __se_compat_sys_ioctl fs/ioctl.c:638 [inline] __ia32_compat_sys_ioctl+0x5ea/0x950 fs/ioctl.c:638 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline] __do_fast_syscall_32+0x229/0x6e0 arch/x86/entry/syscall_32.c:307 do_fast_syscall_32+0x33/0x70 arch/x86/entry/syscall_32.c:332 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7f1601c RSP: 002b:00000000f4f7150c EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 0000000000001276 RDX: 0000000020000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e95cd60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by kworker/u8:5/59: #0: ffff8880b863aea0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:660 #1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 2 locks held by kswapd1/86: 2 locks held by getty/5387: #0: ffff888035d910a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211 8 locks held by kworker/0:7/9263: 1 lock held by syz-executor/16303: #0: ffff8880b863aea0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:660 2 locks held by kworker/u8:8/16685: #0: ffff88801ae84940 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] ffff88801ae84940 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90004587c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90004587c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 2 locks held by kworker/1:1/20211: #0: ffff88813fe43140 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88813fe43140 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc9000410fc40 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc9000410fc40 ((work_completion)(&m->mpeg_thread)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 2 locks held by syz.4.5013/23028: 1 lock held by syz.4.5013/23033: #0: ffff888026e1f868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline] #0: ffff888026e1f868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove+0x20/0x40 kernel/trace/blktrace.c:561 1 lock held by syz.7.5036/23101: #0: ffff888026e1f868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline] #0: ffff888026e1f868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock block/blk.h:770 [inline] #0: ffff888026e1f868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_setup+0x2d3/0x520 kernel/trace/blktrace.c:788 1 lock held by syz.7.5036/23102: #0: ffff888026e1f868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_debugfs_lock_nomemsave block/blk.h:758 [inline] #0: ffff888026e1f868 (&q->debugfs_mutex){+.+.}-{4:4}, at: blk_trace_remove+0x20/0x40 kernel/trace/blktrace.c:561 2 locks held by kworker/u8:7/23604: #0: ffff88801ae84940 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3277 [inline] #0: ffff88801ae84940 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3385 #1: ffffc90003527c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3278 [inline] #1: ffffc90003527c40 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3385 3 locks held by syz.6.5269/23984: 2 locks held by modprobe/23986: 1 lock held by syz.1.5270/23992: 2 locks held by modprobe/23996: ============================================= 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 04/18/2026 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:162 [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:353 [inline] watchdog+0xfd3/0x1030 kernel/hung_task.c:561 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 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: 20253 Comm: kworker/u8:2 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:100 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:115 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:140 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:172 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:191 [inline] RIP: 0010:kasan_check_range+0x9d/0x2c0 mm/kasan/generic.c:200 Code: 34 19 4d 89 f4 4d 29 dc 49 83 fc 10 7f 29 4d 85 e4 0f 84 3d 01 00 00 4c 89 cb 48 f7 d3 4c 01 fb 41 80 3b 00 0f 85 9e 01 00 00 <49> ff c3 48 ff c3 75 ee e9 1d 01 00 00 44 89 dd 83 e5 07 0f 84 b5 RSP: 0000:ffffc90005eef688 EFLAGS: 00000046 RAX: 0000000000000001 RBX: ffffffffffffffff RCX: ffffffff8178d64d RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff9030b6f0 RBP: ffffffff8ea882c0 R08: ffffffff9030b6f7 R09: 1ffffffff20616de R10: dffffc0000000000 R11: fffffbfff20616de R12: 0000000000000001 R13: dffffc0000000000 R14: fffffbfff20616df R15: 1ffffffff20616de FS: 0000000000000000(0000) GS:ffff88812538d000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fe516454e99 CR3: 000000013fe64000 CR4: 00000000003526f0 Call Trace: instrument_atomic_read include/linux/instrumented.h:82 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] cpumask_test_cpu include/linux/cpumask.h:649 [inline] cpu_online include/linux/cpumask.h:1231 [inline] trace_tlb_flush+0x2d/0x160 include/trace/events/tlb.h:39 switch_mm_irqs_off+0x472/0x690 arch/x86/mm/tlb.c:-1 use_temporary_mm+0x98/0x140 arch/x86/mm/tlb.c:1008 __text_poke+0x632/0x9a0 arch/x86/kernel/alternative.c:2608 text_poke arch/x86/kernel/alternative.c:2672 [inline] smp_text_poke_batch_finish+0xd36/0x1160 arch/x86/kernel/alternative.c:3061 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x128/0x240 kernel/jump_label.c:210 static_key_enable+0x1a/0x20 kernel/jump_label.c:223 toggle_allocation_gate+0xab/0x290 mm/kfence/core.c:906 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245