KVM: s390: Clear Crypto Control Block when using vSIE

Pierre Morel · borntraeger · commit 6cc571b1b1e8 · 2018-09-28T15:50:11.000+02:00
When we clear the Crypto Control Block (CRYCB) used by a guest
level 2, the vSIE shadow CRYCB for guest level 3 must be updated
before the guest uses it.

We achieve this by using the KVM_REQ_VSIE_RESTART synchronous
request for each vCPU belonging to the guest to force the reload
of the shadow CRYCB before rerunning the guest level 3.

Signed-off-by: Pierre Morel &lt;pmorel@linux.ibm.com&gt;
Signed-off-by: Tony Krowiak &lt;akrowiak@linux.ibm.com&gt;
Message-Id: &lt;20180925231641.4954-16-akrowiak@linux.vnet.ibm.com&gt;
Signed-off-by: Christian Borntraeger &lt;borntraeger@de.ibm.com&gt;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
@@ -2043,6 +2043,8 @@ void kvm_arch_crypto_clear_masks(struct kvm *kvm)
 	memset(&kvm->arch.crypto.crycb->apcb1, 0,
 	       sizeof(kvm->arch.crypto.crycb->apcb1));
 
+	/* recreate the shadow crycb for each vcpu */
+	kvm_s390_sync_request_broadcast(kvm, KVM_REQ_VSIE_RESTART);
 	kvm_s390_vcpu_unblock_all(kvm);
 	mutex_unlock(&kvm->lock);
 }

Original file line number	Diff line number	Diff line change
`@@ -2043,6 +2043,8 @@ void kvm_arch_crypto_clear_masks(struct kvm *kvm)`
`2043`	`2043`	`memset(&kvm->arch.crypto.crycb->apcb1, 0,`
`2044`	`2044`	`sizeof(kvm->arch.crypto.crycb->apcb1));`
`2045`	`2045`
	`2046`	`+ /* recreate the shadow crycb for each vcpu */`
	`2047`	`+ kvm_s390_sync_request_broadcast(kvm, KVM_REQ_VSIE_RESTART);`
`2046`	`2048`	`kvm_s390_vcpu_unblock_all(kvm);`
`2047`	`2049`	`mutex_unlock(&kvm->lock);`
`2048`	`2050`	`}`