I agree at least in that it probably at least refuse the a MAP_FIXED mmap that would overwrite things the JIT is using. An error message is better than a crash, after all. But changing from a strategy where wine wants to clobber it to one where wine just wants to move it might give qemu-user some better options. I haven't put enough thought into it yet to have a specific idea, just that this PR seemed like it would be helpful.