INFO: task syz-fuzzer:3702 blocked for more than 143 seconds. Not tainted 6.1.27-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-fuzzer state:D stack:22152 pid:3702 ppid:3538 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x132c/0x4330 kernel/sched/core.c:6554 schedule+0xbf/0x180 kernel/sched/core.c:6630 rwsem_down_write_slowpath+0xe93/0x14a0 kernel/locking/rwsem.c:1189 inode_lock include/linux/fs.h:756 [inline] vfs_unlink+0xe0/0x5f0 fs/namei.c:4241 do_unlinkat+0x49d/0x940 fs/namei.c:4320 __do_sys_unlinkat fs/namei.c:4363 [inline] __se_sys_unlinkat fs/namei.c:4356 [inline] __x64_sys_unlinkat+0xca/0xf0 fs/namei.c:4356 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x403ace RSP: 002b:000000c000ba14b8 EFLAGS: 00000206 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000016 RCX: 0000000000403ace RDX: 0000000000000000 RSI: 000000c023780030 RDI: 0000000000000016 RBP: 000000c000ba14f8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000003 R14: 000000c0118ac000 R15: 000000c024e74800 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cf273f0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cf27bf0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xd20 kernel/rcu/tasks.h:510 1 lock held by khungtaskd/28: #0: ffffffff8cf27220 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by syslogd/2982: 2 locks held by getty/3306: #0: ffff888029861098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2177 3 locks held by syz-fuzzer/3702: #0: ffff88807ef6a460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:393 #1: ffff888088db5e48 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:791 [inline] #1: ffff888088db5e48 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x260/0x940 fs/namei.c:4303 #2: ffff88808758f258 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline] #2: ffff88808758f258 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xe0/0x5f0 fs/namei.c:4241 2 locks held by kworker/u4:13/4102: 3 locks held by syz-executor.1/10604: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.27-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xf18/0xf60 kernel/hung_task.c:377 kthread+0x26e/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3612 Comm: kworker/u4:3 Not tainted 6.1.27-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet RIP: 0010:check_preemption_disabled+0x5c/0x110 lib/smp_processor_id.c:19 Code: 25 28 00 00 00 48 3b 44 24 08 0f 85 c7 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5e 41 5f c3 48 c7 04 24 00 00 00 00 9c 8f 04 24 04 24 00 02 00 00 74 c9 49 89 f6 49 89 ff 65 4c 8b 25 bd dd 80 RSP: 0018:ffffc90003ebf8a8 EFLAGS: 00000046 RAX: 0000000080000000 RBX: 0000000000000000 RCX: 1ffff920007d7ec8 RDX: dffffc0000000000 RSI: ffffffff8aebe1a0 RDI: ffffffff8b3cbfa0 RBP: ffffc90003ebfa40 R08: dffffc0000000000 R09: fffffbfff2050445 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920007d7f24 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000246 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c02452a8f0 CR3: 000000000cc8e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lockdep_recursion_finish kernel/locking/lockdep.c:467 [inline] lock_acquire+0x208/0x5a0 kernel/locking/lockdep.c:5671 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:306 rcu_read_lock include/linux/rcupdate.h:747 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline] batadv_iv_ogm_schedule_buff net/batman-adv/bat_iv_ogm.c:826 [inline] batadv_iv_ogm_schedule+0x425/0x1000 net/batman-adv/bat_iv_ogm.c:869 batadv_iv_send_outstanding_bat_ogm_packet+0x6fa/0x800 net/batman-adv/bat_iv_ogm.c:1713 process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2289 worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436 kthread+0x26e/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306