============================================ WARNING: possible recursive locking detected 6.7.0-rc1-syzkaller-00019-gc42d9eeef8e5 #0 Not tainted -------------------------------------------- syz-executor.5/5855 is trying to acquire lock: ffff888025709468 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline] ffff888025709468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x136/0x1a40 fs/pipe.c:453 but task is already holding lock: ffff88802570b068 (&pipe->mutex/1){+.+.}-{3:3}, at: iter_file_splice_write+0x2d9/0x1010 fs/splice.c:683 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.5/5855: #0: ffff88802570b068 (&pipe->mutex/1){+.+.}-{3:3}, at: iter_file_splice_write+0x2d9/0x1010 fs/splice.c:683 stack backtrace: CPU: 0 PID: 5855 Comm: syz-executor.5 Not tainted 6.7.0-rc1-syzkaller-00019-gc42d9eeef8e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023 Call Trace: __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+0x15b8/0x59f0 kernel/locking/lockdep.c:3855 __lock_acquire+0x1345/0x1fd0 kernel/locking/lockdep.c:5136 lock_acquire+0x1e3/0x530 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_readv_writev+0x330/0x4a0 do_iter_write+0x1f6/0x8d0 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+0x45/0x110 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x63/0x6b RIP: 0033:0x7f4628c7cae9 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:00007f46299c70c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00007f4628d9c050 RCX: 00007f4628c7cae9 RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f4628cc847a R08: 0000000000007fff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f4628d9c050 R15: 00007ffe115f8858