============================================
WARNING: possible recursive locking detected
6.6.0-syzkaller-06824-g8bc9e6515183 #0 Not tainted
--------------------------------------------
syz-executor280/5053 is trying to acquire lock:
ffff88802004bc68 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline]
ffff88802004bc68 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x136/0x1a40 fs/pipe.c:453

but task is already holding lock:
ffff88802004b868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline]
ffff88802004b868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock fs/pipe.c:90 [inline]
ffff88802004b868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x3e3/0x550 fs/pipe.c:1063

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-executor280/5053:
 #0: ffff88802004b868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline]
 #0: ffff88802004b868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock fs/pipe.c:90 [inline]
 #0: ffff88802004b868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x3e3/0x550 fs/pipe.c:1063

stack backtrace:
CPU: 0 PID: 5053 Comm: syz-executor280 Not tainted 6.6.0-syzkaller-06824-g8bc9e6515183 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 check_deadlock kernel/locking/lockdep.c:3062 [inline]
 validate_chain kernel/locking/lockdep.c:3855 [inline]
 __lock_acquire+0x6a81/0x7f70 kernel/locking/lockdep.c:5136
 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5753
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x136/0xd60 kernel/locking/mutex.c:747
 __pipe_lock fs/pipe.c:103 [inline]
 pipe_write+0x136/0x1a40 fs/pipe.c:453
 do_iter_write+0x7ac/0xcb0 fs/read_write.c:860
 iter_file_splice_write+0x86d/0x1010 fs/splice.c:736
 do_splice_from fs/splice.c:933 [inline]
 do_splice+0xf66/0x1d60 fs/splice.c:1292
 __do_splice fs/splice.c:1370 [inline]
 __do_sys_splice fs/splice.c:1586 [inline]
 __se_sys_splice+0x331/0x4a0 fs/splice.c:1568
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f2e09390fb9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 17 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2e09353188 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00007f2e0941a348 RCX: 00007f2e09390fb9
RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 00007f2e0941a340 R08: 0000000000000100 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2e093e8040
R13: 00007f2e093531a0 R14: 00007f2e093e8012 R15: 00000000fffffeed
 </TASK>