tree 67b5df8e42e7db5f1f59f7d851b97923b5336678
parent d4cb11340be6a1613d40d2b546cb111ea2547066
author Dominik Dingel <dingel@linux.vnet.ibm.com> 1389719417 +0100
committer Christian Borntraeger <borntraeger@de.ibm.com> 1398152185 +0200

KVM: s390: Allow skeys to be enabled for the current process

Introduce a new function s390_enable_skey(), which enables storage key
handling via setting the use_skey flag in the mmu context.

This function is only useful within the context of kvm.

Note that enabling storage keys will cause a one-time hickup when
walking the page table; however, it saves us special effort for cases
like clear reset while making it possible for us to be architecture
conform.

s390_enable_skey() takes the page table lock to prevent reseting
storage keys triggered from multiple vcpus.

Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>