============================================
WARNING: possible recursive locking detected
6.5.0-rc1-syzkaller-00201-g2772d7df3c93 #0 Not tainted
--------------------------------------------
syz-executor.3/14797 is trying to acquire lock:
ffff888039dc7c68 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline]
ffff888039dc7c68 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x140/0x1cc0 fs/pipe.c:432

but task is already holding lock:
ffff888039dc7468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline]
ffff888039dc7468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock fs/pipe.c:90 [inline]
ffff888039dc7468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock+0x5e/0x70 fs/pipe.c:85

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.3/14797:
 #0: ffff888039dc7468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline]
 #0: ffff888039dc7468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock fs/pipe.c:90 [inline]
 #0: ffff888039dc7468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock+0x5e/0x70 fs/pipe.c:85

stack backtrace:
CPU: 1 PID: 14797 Comm: syz-executor.3 Not tainted 6.5.0-rc1-syzkaller-00201-g2772d7df3c93 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 check_deadlock kernel/locking/lockdep.c:3070 [inline]
 validate_chain kernel/locking/lockdep.c:3863 [inline]
 __lock_acquire+0x2971/0x5de0 kernel/locking/lockdep.c:5144
 lock_acquire kernel/locking/lockdep.c:5761 [inline]
 lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5726
 __mutex_lock_common kernel/locking/mutex.c:603 [inline]
 __mutex_lock+0x181/0x1340 kernel/locking/mutex.c:747
 __pipe_lock fs/pipe.c:103 [inline]
 pipe_write+0x140/0x1cc0 fs/pipe.c:432
 call_write_iter include/linux/fs.h:1871 [inline]
 do_iter_readv_writev+0x21e/0x3c0 fs/read_write.c:735
 do_iter_write+0x17f/0x830 fs/read_write.c:860
 vfs_iter_write+0x7a/0xb0 fs/read_write.c:901
 iter_file_splice_write+0x698/0xbf0 fs/splice.c:739
 do_splice_from fs/splice.c:934 [inline]
 do_splice+0xef0/0x1e40 fs/splice.c:1295
 __do_splice+0x323/0x360 fs/splice.c:1373
 __do_sys_splice fs/splice.c:1584 [inline]
 __se_sys_splice fs/splice.c:1566 [inline]
 __x64_sys_splice+0x1ce/0x260 fs/splice.c:1566
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4c07e7cb29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007f4c08c1b0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 00007f4c07f9bf80 RCX: 00007f4c07e7cb29
RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f4c07ec847a R08: 0000000080000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f4c07f9bf80 R15: 00007f4c080bfa48
 </TASK>