[Xen-devel] HYPERVISOR_update_va_mapping in mm/memory.c

[Jacob G. H. <ja...@di...>]

hi,

I am trying to guess the purpose of the calls to
HYPERVISOR_update_va_mapping in mm/memory.c, or rather why this code
(which apparently handles user space demand paging) uses a special
hypercall rather than the usual pte-update calls.

Could anyone briefly explain to me what this hypercall does, and why it
needs to be special?

thanks,
Jacob