panic: inconsistent poll.fdMutex

goroutine 2936 [running]:
internal/poll.(*fdMutex).rwunlock(0xc0004a2e28?, 0xc7?)
	/usr/local/go/src/internal/poll/fd_mutex.go:179 +0xde
internal/poll.(*FD).readUnlock(0xc0003c91a0)
	/usr/local/go/src/internal/poll/fd_mutex.go:231 +0x1f
internal/poll.(*FD).Read(0xc0003c91a0, {0xc00038a988, 0x4, 0x4})
	/usr/local/go/src/internal/poll/fd_unix.go:170 +0x351
os.(*File).read(...)
	/usr/local/go/src/os/file_posix.go:29
os.(*File).Read(0xc000332b28, {0xc00038a988?, 0xc0004a2f48?, 0x411ae5?})
	/usr/local/go/src/os/file.go:118 +0x52
io.ReadAtLeast({0xd8e000, 0xc000332b28}, {0xc00038a988, 0x4, 0x4}, 0x4)
	/usr/local/go/src/io/io.go:335 +0x90
io.ReadFull(...)
	/usr/local/go/src/io/io.go:354
github.com/google/syzkaller/pkg/ipc.(*command).handshake.func1()
	/syzkaller/gopath/src/github.com/google/syzkaller/pkg/ipc/ipc.go:704 +0x5e
created by github.com/google/syzkaller/pkg/ipc.(*command).handshake in goroutine 56
	/syzkaller/gopath/src/github.com/google/syzkaller/pkg/ipc/ipc.go:701 +0x14d