============================================ WARNING: possible recursive locking detected 6.1.78-syzkaller #0 Not tainted -------------------------------------------- syz-executor.4/18651 is trying to acquire lock: ffff88803eced868 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline] ffff88803eced868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x12d/0x1af0 fs/pipe.c:431 but task is already holding lock: ffff88808070c868 (&pipe->mutex/1){+.+.}-{3:3}, at: iter_file_splice_write+0x2d5/0xfc0 fs/splice.c:631 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.4/18651: #0: ffff88808070c868 (&pipe->mutex/1){+.+.}-{3:3}, at: iter_file_splice_write+0x2d5/0xfc0 fs/splice.c:631 stack backtrace: CPU: 1 PID: 18651 Comm: syz-executor.4 Not tainted 6.1.78-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2983 [inline] check_deadlock kernel/locking/lockdep.c:3026 [inline] validate_chain+0x4711/0x5950 kernel/locking/lockdep.c:3812 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5049 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __mutex_lock_common kernel/locking/mutex.c:603 [inline] __mutex_lock+0x132/0xd80 kernel/locking/mutex.c:747 __pipe_lock fs/pipe.c:103 [inline] pipe_write+0x12d/0x1af0 fs/pipe.c:431 do_iter_write+0x6e6/0xc50 fs/read_write.c:861 iter_file_splice_write+0x830/0xfc0 fs/splice.c:685 do_splice_from fs/splice.c:763 [inline] do_splice+0xfdb/0x1790 fs/splice.c:1102 __do_splice fs/splice.c:1167 [inline] __do_sys_splice fs/splice.c:1374 [inline] __se_sys_splice+0x340/0x420 fs/splice.c:1356 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f305967dda9 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:00007f305a4890c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00007f30597ac050 RCX: 00007f305967dda9 RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f30596ca47a R08: 0000000000007fff R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f30597ac050 R15: 00007ffcce301dc8