============================================ WARNING: possible recursive locking detected 6.5.0-rc7-syzkaller-gfe4469582053 #0 Not tainted -------------------------------------------- syz-executor.2/14803 is trying to acquire lock: ffff0000d67cd468 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:103 [inline] ffff0000d67cd468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_write+0x108/0x19c8 fs/pipe.c:432 but task is already holding lock: ffff0000dd1a4068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline] ffff0000dd1a4068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock+0x68/0x98 fs/pipe.c:90 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.2/14803: #0: ffff0000dd1a4068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock_nested fs/pipe.c:82 [inline] #0: ffff0000dd1a4068 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_lock+0x68/0x98 fs/pipe.c:90 stack backtrace: CPU: 1 PID: 14803 Comm: syz-executor.2 Not tainted 6.5.0-rc7-syzkaller-gfe4469582053 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 dump_stack+0x1c/0x28 lib/dump_stack.c:113 print_deadlock_bug+0x4e4/0x660 kernel/locking/lockdep.c:3020 check_deadlock kernel/locking/lockdep.c:3070 [inline] validate_chain kernel/locking/lockdep.c:3863 [inline] __lock_acquire+0x5fd0/0x75e8 kernel/locking/lockdep.c:5144 lock_acquire+0x23c/0x71c kernel/locking/lockdep.c:5761 __mutex_lock_common+0x190/0x21a0 kernel/locking/mutex.c:603 __mutex_lock kernel/locking/mutex.c:747 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:799 __pipe_lock fs/pipe.c:103 [inline] pipe_write+0x108/0x19c8 fs/pipe.c:432 do_iter_write+0x65c/0xaa8 fs/read_write.c:860 vfs_iter_write+0x88/0xac fs/read_write.c:901 iter_file_splice_write+0x628/0xc58 fs/splice.c:739 do_splice_from fs/splice.c:936 [inline] do_splice+0x1040/0x1bcc fs/splice.c:1297 __do_splice fs/splice.c:1375 [inline] __do_sys_splice fs/splice.c:1586 [inline] __se_sys_splice fs/splice.c:1568 [inline] __arm64_sys_splice+0x490/0x804 fs/splice.c:1568 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x58/0x16c arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591