On 02/17/2017 06:13 AM, Kirill A. Shutemov wrote: > +/* > + * Default maximum virtual address. This is required for > + * compatibility with applications that assumes 47-bit VA. > + * The limit can be changed with prctl(PR_SET_MAX_VADDR). > + */ > +#define MAX_VADDR_DEFAULT ((1UL << 47) - PAGE_SIZE) This is a bit goofy. It's not the largest virtual adddress that can be accessed, but the beginning of the last page. Isn't this easier to deal with in userspace if we make it a "limit", so we can do: if (addr >= limit) // error Now, we have to do: prctl(PR_GET_MAX_VADDR, &max_vaddr, 0, 0, 0); if (addr > (max_vaddr + PAGE_SIZE)) // error I don't care what you track in the kernel, but I think we need to provide a more usable number out to userspace.
