============================================ WARNING: possible recursive locking detected 5.17.0-rc8-syzkaller-00003-g56e337f2cf13 #0 Not tainted -------------------------------------------- syz-executor295/3592 is trying to acquire lock: ffff888078eeb068 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline] ffff888078eeb068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x12f/0x1b10 fs/pipe.c:431 but task is already holding lock: ffff888078eea868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline] ffff888078eea868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock fs/pipe.c:90 [inline] ffff888078eea868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x3d7/0x550 fs/pipe.c:1049 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-executor295/3592: #0: ffff888078eea868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline] #0: ffff888078eea868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock fs/pipe.c:90 [inline] #0: ffff888078eea868 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_wait_readable+0x3d7/0x550 fs/pipe.c:1049 stack backtrace: CPU: 0 PID: 3592 Comm: syz-executor295 Not tainted 5.17.0-rc8-syzkaller-00003-g56e337f2cf13 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain+0x598d/0x8250 kernel/locking/lockdep.c:3788 __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5027 lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5639 __mutex_lock_common+0x1d5/0x2590 kernel/locking/mutex.c:600 __mutex_lock kernel/locking/mutex.c:733 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:785 __pipe_lock fs/pipe.c:103 [inline] pipe_write+0x12f/0x1b10 fs/pipe.c:431 do_iter_readv_writev+0x54f/0x740 do_iter_write+0x21e/0x7b0 fs/read_write.c:851 iter_file_splice_write+0x7eb/0xfa0 fs/splice.c:689 do_splice_from fs/splice.c:767 [inline] do_splice+0xec9/0x1810 fs/splice.c:1079 __do_splice fs/splice.c:1144 [inline] __do_sys_splice fs/splice.c:1350 [inline] __se_sys_splice+0x2a8/0x410 fs/splice.c:1332 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fee6bd86ca9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 14 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fee6bd39308 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 00007fee6be0f408 RCX: 00007fee6bd86ca9