[PATCH] Fixes for more than 32 VCPUs migration for HVM guests (v1).

[konrad@kernel.org]

These two patches (one for Linux, one for Xen) allow PVHVM guests to use
the per-cpu VCPU mechanism after migration. Currently when an PVHVM guest
migrates all the per-cpu information is lost and we fallback on the
shared_info structure. This is regardless if the HVM guest has 2 or 128 CPUs.
Since the structure has an array for only 32 CPUs that means if we are
to migrate a PVHVM guest - we can only do it up to 32 CPUs.

These patches fix it and allow more than 32 VCPUs to be migrated with
PVHVM Linux guests.

The Linux diff is:

 arch/x86/xen/enlighten.c |   21 ++++++++++++++++-----
 arch/x86/xen/suspend.c   |    6 +-----
 arch/x86/xen/time.c      |    3 +++
 3 files changed, 20 insertions(+), 10 deletions(-)

while the Xen one is:

 xen/arch/x86/hvm/hvm.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)