============================================ WARNING: possible recursive locking detected 6.5.0-rc1-syzkaller-00201-g2772d7df3c93 #0 Not tainted -------------------------------------------- syz-executor.1/15872 is trying to acquire lock: ffff88803c429868 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline] ffff88803c429868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x13e/0x1be0 fs/pipe.c:432 but task is already holding lock: ffff88803bf92c68 (&pipe->mutex/1){+.+.}-{3:3}, at: iter_file_splice_write+0x2d9/0x1010 fs/splice.c:686 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.1/15872: #0: ffff88803bf92c68 (&pipe->mutex/1){+.+.}-{3:3}, at: iter_file_splice_write+0x2d9/0x1010 fs/splice.c:686 stack backtrace: CPU: 1 PID: 15872 Comm: syz-executor.1 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: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 check_deadlock kernel/locking/lockdep.c:3070 [inline] validate_chain kernel/locking/lockdep.c:3863 [inline] __lock_acquire+0x6a81/0x7f70 kernel/locking/lockdep.c:5144 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5761 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799 __pipe_lock fs/pipe.c:103 [inline] pipe_write+0x13e/0x1be0 fs/pipe.c:432 do_iter_write+0x84f/0xde0 fs/read_write.c:860 iter_file_splice_write+0x86d/0x1010 fs/splice.c:739 do_splice_from fs/splice.c:934 [inline] do_splice+0xf13/0x1a60 fs/splice.c:1295 __do_splice fs/splice.c:1373 [inline] __do_sys_splice fs/splice.c:1584 [inline] __se_sys_splice+0x331/0x4a0 fs/splice.c:1566 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fa28fc7cb29 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:00007fa290a080c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00007fa28fd9bf80 RCX: 00007fa28fc7cb29 RDX: 0000000000000006 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007fa28fcc847a R08: 0000000080000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fa28fd9bf80 R15: 00007ffef4ccbdc8