INFO: task kworker/0:0:9 blocked for more than 143 seconds. Not tainted 6.16.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:0 state:D stack:24168 pid:9 tgid:9 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events_long flush_mdb Call Trace: context_switch kernel/sched/core.c:5396 [inline] __schedule+0x16f5/0x4d00 kernel/sched/core.c:6785 __schedule_loop kernel/sched/core.c:6863 [inline] schedule+0x165/0x360 kernel/sched/core.c:6878 io_schedule+0x80/0xd0 kernel/sched/core.c:7723 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:247 __wait_on_bit_lock+0xec/0x4f0 kernel/sched/wait_bit.c:90 out_of_line_wait_on_bit_lock+0x123/0x170 kernel/sched/wait_bit.c:117 lock_buffer include/linux/buffer_head.h:434 [inline] hfs_mdb_commit+0xb0d/0x1160 fs/hfs/mdb.c:325 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 2 locks held by kworker/0:0/9: #0: ffff88801a479548 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801a479548 ((wq_completion)events_long){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321 #1: ffffc900000e7bc0 ((work_completion)(&(&sbi->mdb_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900000e7bc0 ((work_completion)(&(&sbi->mdb_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321 1 lock held by khungtaskd/31: #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770 2 locks held by getty/5591: #0: ffff88814c6f50a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc1-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:307 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:470 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 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: 5854 Comm: syz-executor243 Not tainted 6.16.0-rc1-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0x2e/0xb0 kernel/rcu/tree.c:745 Code: 41 57 41 56 53 65 ff 05 e0 b9 f5 10 e8 8b fb be 09 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd 60 6c ba 8d <4c> 89 f0 48 c1 e8 03 42 80 3c 38 00 74 08 4c 89 f7 e8 dc af 7c 00 RSP: 0018:ffffc90003e1f278 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 7604d701296ee300 RDX: ffffc90003e1f301 RSI: ffffffff8be282a0 RDI: ffffffff8be28260 RBP: dffffc0000000000 R08: ffffc90003e1f758 R09: ffffc90003e1f3b8 R10: dffffc0000000000 R11: fffff520007c3e79 R12: ffffc90003e1f768 R13: ffffc90003e18000 R14: ffffffff8dba6c60 R15: dffffc0000000000 FS: 0000555570637380(0000) GS:ffff888125c52000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe55baab28 CR3: 0000000076f71000 CR4: 0000000000350ef0 Call Trace: rcu_read_unlock include/linux/rcupdate.h:869 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x1965/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 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 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4148 [inline] slab_alloc_node mm/slub.c:4197 [inline] kmem_cache_alloc_noprof+0x1c1/0x3c0 mm/slub.c:4204 radix_tree_node_alloc+0x19c/0x3a0 lib/radix-tree.c:253 idr_get_free+0x2b3/0xa70 lib/radix-tree.c:1506 idr_alloc_u32+0x159/0x2d0 lib/idr.c:46 idr_alloc_cyclic+0x9b/0x1b0 lib/idr.c:125 alloc_pid+0x33a/0xab0 kernel/pid.c:237 copy_process+0x198e/0x3c00 kernel/fork.c:2185 kernel_clone+0x21e/0x870 kernel/fork.c:2599 __do_sys_clone kernel/fork.c:2742 [inline] __se_sys_clone kernel/fork.c:2726 [inline] __x64_sys_clone+0x18b/0x1e0 kernel/fork.c:2726 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5d75d87dc3 Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00 RSP: 002b:00007ffe55bab1d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5d75d87dc3 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000000 R08: 0000000000000000 R09: 00007ffe55bab027 R10: 0000555570637650 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffe55bab2ec R14: 431bde82d7b634db R15: 00007f5d75dd303b INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.829 msecs