INFO: task syz.1.1137:9979 blocked for more than 145 seconds. Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.1.1137 state:D stack:23960 pid:9979 tgid:9979 ppid:5820 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x168f/0x4c70 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148 __flush_work+0x9b9/0xbc0 kernel/workqueue.c:4244 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4364 uhid_dev_destroy drivers/hid/uhid.c:584 [inline] uhid_char_release+0xac/0x600 drivers/hid/uhid.c:662 __fput+0x449/0xa70 fs/file_table.c:465 task_work_run+0x1d1/0x260 kernel/task_work.c:227 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ffbe178e969 RSP: 002b:00007ffdc8a08218 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007ffbe19b7ba0 RCX: 00007ffbe178e969 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007ffbe19b7ba0 R08: 0000000000000218 R09: 0000001ec8a0850f R10: 00000000003ffbc4 R11: 0000000000000246 R12: 000000000009928c R13: 00007ffbe19b6080 R14: ffffffffffffffff R15: 00007ffdc8a08330 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8df3b860 ( rcu_read_lock ){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] ){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] ){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 2 locks held by getty/5572: #0: ffff88803071c0a0 (&tty->ldisc_sem){++++}-{0:0} , at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 1 lock held by syz-executor/5818: #0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline] ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998 8 locks held by kworker/0:5/5873: 1 lock held by syz-executor/7901: #0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline] (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b7/0x730 kernel/rcu/tree_exp.h:998 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 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: 5873 Comm: kworker/0:5 Not tainted 6.15.0-rc3-syzkaller-00342-g5bc1018675ec #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Workqueue: events uhid_device_add_worker RIP: 0010:stack_trace_consume_entry+0x0/0x280 kernel/stacktrace.c:83 Code: 75 0e 48 8d 65 f0 5b 41 5e 5d c3 cc cc cc cc cc e8 e5 ec a1 09 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 18 48 ba 00 00 RSP: 0018:ffffc900000077a0 EFLAGS: 00000286 RAX: ffffffff85e42c65 RBX: ffffc90000007860 RCX: 9d59d1be023e2a00 RDX: 0000000000000001 RSI: ffffffff85e42c65 RDI: ffffc90000007860 RBP: ffffc90000007830 R08: ffffc900045efa08 R09: 0000000000000000 R10: ffffc900000077f8 R11: ffffffff81aca990 R12: ffff888034670000 R13: 0000000000000000 R14: ffffffff81aca990 R15: ffffc900000077a8 FS: 0000000000000000(0000) GS:ffff888126102000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd05cd7d2d8 CR3: 0000000029582000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: arch_stack_walk+0x10d/0x150 arch/x86/kernel/stacktrace.c:27 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2398 [inline] slab_free mm/slub.c:4656 [inline] kfree+0x193/0x440 mm/slub.c:4855 slab_free_after_rcu_debug+0x62/0x290 mm/slub.c:4693 rcu_do_batch kernel/rcu/tree.c:2568 [inline] rcu_core+0xca5/0x1710 kernel/rcu/tree.c:2824 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline] RIP: 0010:vprintk_emit+0x58f/0x7a0 kernel/printk/printk.c:2449 Code: 85 32 01 00 00 e8 31 f3 1e 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 20 f3 1e 00 eb 06 e8 19 f3 1e 00 fb 48 c7 c7 80 fa f2 8d <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 f9 3f RSP: 0018:ffffc900045ef100 EFLAGS: 00000293 RAX: ffffffff81a0cac7 RBX: ffffffff81a0c984 RCX: ffff888034670000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8df2fa80 RBP: ffffc900045ef210 R08: ffffffff8f7d9f77 R09: 1ffffffff1efb3ee R10: dffffc0000000000 R11: fffffbfff1efb3ef R12: dffffc0000000000 R13: 1ffff920008bde24 R14: 0000000000000200 R15: 000000000000003a dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4917 dev_printk_emit+0xe0/0x130 drivers/base/core.c:4928 _dev_warn+0x10a/0x160 drivers/base/core.c:4984 hid_parser_main+0x8b8/0xc40 drivers/hid/hid-core.c:-1 hid_open_report+0x858/0xee0 drivers/hid/hid-core.c:1328 hid_parse include/linux/hid.h:1126 [inline] hid_generic_probe+0x3d/0x90 drivers/hid/hid-generic.c:66 __hid_device_probe drivers/hid/hid-core.c:2717 [inline] hid_device_probe+0x397/0x710 drivers/hid/hid-core.c:2754 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x26a/0x9a0 drivers/base/dd.c:657 __driver_probe_device+0x18c/0x2f0 drivers/base/dd.c:799 driver_probe_device+0x4f/0x430 drivers/base/dd.c:829 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:957 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x2b8/0x400 drivers/base/dd.c:1029 bus_probe_device+0x185/0x260 drivers/base/bus.c:537 device_add+0x7b6/0xb50 drivers/base/core.c:3692 hid_add_device+0x398/0x540 drivers/hid/hid-core.c:2900 uhid_device_add_worker+0x43/0xf0 drivers/hid/uhid.c:73 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x70e/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245