============================================
WARNING: possible recursive locking detected
5.17.0-syzkaller-13966-g8467b0ed6ce3 #0 Not tainted
--------------------------------------------
syz-executor.3/25361 is trying to acquire lock:
ffff888073251068 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline]
ffff888073251068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x12f/0x1b00 fs/pipe.c:431

but task is already holding lock:
ffff88807ce09068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline]
ffff88807ce09068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock fs/pipe.c:90 [inline]
ffff88807ce09068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x3d7/0x550 fs/pipe.c:1049

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&pipe->mutex/1);
  lock(&pipe->mutex/1);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

1 lock held by syz-executor.3/25361:
 #0: ffff88807ce09068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline]
 #0: ffff88807ce09068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock fs/pipe.c:90 [inline]
 #0: ffff88807ce09068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x3d7/0x550 fs/pipe.c:1049

stack backtrace:
CPU: 0 PID: 25361 Comm: syz-executor.3 Not tainted 5.17.0-syzkaller-13966-g8467b0ed6ce3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2958 [inline]
 check_deadlock kernel/locking/lockdep.c:3001 [inline]
 validate_chain+0x598d/0x8250 kernel/locking/lockdep.c:3790
 __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5029
 lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5641
 __mutex_lock_common+0x1d5/0x2590 kernel/locking/mutex.c:600
 __mutex_lock kernel/locking/mutex.c:733 [inline]
 mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:785
 __pipe_lock fs/pipe.c:103 [inline]
 pipe_write+0x12f/0x1b00 fs/pipe.c:431
 do_iter_readv_writev+0x4d2/0x670
 do_iter_write+0x21b/0x7b0 fs/read_write.c:852
 iter_file_splice_write+0x7eb/0xfa0 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 do_splice+0xeb6/0x1800 fs/splice.c:1079
 __do_splice fs/splice.c:1144 [inline]
 __do_sys_splice fs/splice.c:1350 [inline]
 __se_sys_splice+0x2a8/0x410 fs/splice.c:1332
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x50 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f670e889049
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f670fad7168 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00007f670e99bf60 RCX: 00007f670e889049
RDX: 000000000000000e RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007f670e8e308d R08: 00000000000001ff R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffe826a99f R14: 00007f670fad7300 R15: 0000000000022000
 </TASK>