INFO: task syz-fuzzer:5064 blocked for more than 143 seconds.
      Not tainted 6.8.0-rc4-next-20240214-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-fuzzer      state:D stack:21840 pid:5064  tgid:5056  ppid:5054   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0x17df/0x4a40 kernel/sched/core.c:6727
 __schedule_loop kernel/sched/core.c:6804 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6819
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6876
 rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
 __down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306
 inode_lock include/linux/fs.h:802 [inline]
 vfs_unlink+0xe4/0x600 fs/namei.c:4321
 do_unlinkat+0x4ae/0x830 fs/namei.c:4396
 __do_sys_unlinkat fs/namei.c:4439 [inline]
 __se_sys_unlinkat fs/namei.c:4432 [inline]
 __x64_sys_unlinkat+0xce/0xf0 fs/namei.c:4432
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x40720e
RSP: 002b:000000c02fc59560 EFLAGS: 00000212 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 0000000000000016 RCX: 000000000040720e
RDX: 0000000000000000 RSI: 000000c024e53cc0 RDI: 0000000000000016
RBP: 000000c02fc595a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000212 R12: 00000000000001cc
R13: 000000c0001fa800 R14: 000000c00ecc41a0 R15: 000000c02b194280
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8e1315a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 #0: ffffffff8e1315a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
 #0: ffffffff8e1315a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614
2 locks held by getty/4818:
 #0: ffff88802dbc80a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201
3 locks held by syz-fuzzer/5064:
 #0: ffff88801d9ae420 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:409
 #1: ffff88801d306800 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:837 [inline]
 #1: ffff88801d306800 (&type->i_mutex_dir_key#3/1){+.+.}-{3:3}, at: do_unlinkat+0x26a/0x830 fs/namei.c:4383
 #2: ffff88807677ac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: inode_lock include/linux/fs.h:802 [inline]
 #2: ffff88807677ac00 (&sb->s_type->i_mutex_key#8){++++}-{3:3}, at: vfs_unlink+0xe4/0x600 fs/namei.c:4321
4 locks held by syz-executor.3/6215:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc4-next-20240214-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
 watchdog+0xfb0/0xff0 kernel/hung_task.c:380
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 6935 Comm: kworker/u8:4 Not tainted 6.8.0-rc4-next-20240214-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Workqueue: bat_events batadv_nc_worker
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4773 [inline]
RIP: 0010:__lock_acquire+0x58c/0x1fd0 kernel/locking/lockdep.c:5087
Code: 8b e8 78 31 e6 ff 48 ba 00 00 00 00 00 fc ff df 90 0f 0b 90 90 90 31 db 48 81 c3 c4 00 00 00 48 89 d8 48 c1 e8 03 0f b6 04 10 <84> c0 0f 85 39 12 00 00 0f b6 2b 48 8b 44 24 20 0f b6 04 10 84 c0
RSP: 0018:ffffc9000f1ef8f0 EFLAGS: 00000807
RAX: 0000000000000000 RBX: ffffffff929aae2c RCX: ffffffff8171848b
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff92cc34a0
RBP: 000000000000000a R08: ffffffff92cc34a7 R09: 1ffffffff2598694
R10: dffffc0000000000 R11: fffffbfff2598695 R12: 0000000000000000
R13: ffff88801f970000 R14: 000000000000000a R15: ffff88801f970b48
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c00dd18a70 CR3: 000000000df32000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
 rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 rcu_read_lock include/linux/rcupdate.h:750 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719
 process_one_work kernel/workqueue.c:3146 [inline]
 process_scheduled_works+0x9d7/0x1730 kernel/workqueue.c:3226
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3307
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242
 </TASK>