KVM: s390: forward ESOP if available
ESOP guarantees that during a protection exception, bit 61 of real location 168-175 will only be set to 1 if it was because of ALCP or DATP. If the exception is due to LAP or KCP, the bit will always be set to 0. The old SOP definition allowed bit 61 to be unpredictable in case of LAP or KCP in some conditions. So ESOP replaces this unpredictability by a guarantee. Therefore, we can directly forward ESOP if it is available on our machine. We don't have to do anything when ESOP is disabled - the guest will simply expect unpredictable values. Our guest access functions are already handling ESOP properly. Please note that future functionality in KVM will require knowledge about ESOP being enabled for a guest or not. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
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