[PATCH for-4.19? 0/2] xen/x86: support foreign mappings for HVM

[Roger Pau Monne <roger.pau@xxxxxxxxxx>]

Hello,

The following series attempts to solve a shortcoming of HVM/PVH guests
with the lack of support for foreign mappings.  Such lack of support
prevents using PVH based guests as stubdomains for example.

Add support in a way similar to how it was done on Arm, by iterating
over the p2m based on the maximum gfn.

Mostly untested, sending early in case it could be considered for 4.19.

Thanks, Roger.

Roger Pau Monne (2):
  xen/x86: account for max guest gfn and number of foreign mappings in
    the p2m
  xen/x86: remove foreign mappings from the p2m on teardown

 CHANGELOG.md                   |  1 +
 xen/arch/x86/domain.c          |  6 +++
 xen/arch/x86/include/asm/p2m.h | 28 ++++++++++----
 xen/arch/x86/mm/p2m.c          | 70 ++++++++++++++++++++++++++++++++--
 4 files changed, 94 insertions(+), 11 deletions(-)

-- 
2.44.0