[PATCH RFC 0/2] KVM: s390: vsie: protect from VCPUS modifying the SCB

[David Hildenbrand <david@xxxxxxxxxx>]

As the (nested) SCB is just guest memory, other VCPUs can try to modify it
while we are building our shadow SCB.

Let's avoid unpredictable behavior by adding some READ_ONCE and refactoring
unpinning of satellite control blocks.

Compile tested only for now.

David Hildenbrand (2):
  KVM: s390 vsie: use READ_ONCE to access some SCB fields
  KVM: s390: vsie: store guest addresses of satellite blocks in
    vsie_page

 arch/s390/kvm/vsie.c | 87 ++++++++++++++++++++++++++++++++--------------------
 1 file changed, 53 insertions(+), 34 deletions(-)

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2.14.3