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Diffstat (limited to 'arch/s390/kvm/guestdbg.c')
-rw-r--r--arch/s390/kvm/guestdbg.c35
1 files changed, 35 insertions, 0 deletions
diff --git a/arch/s390/kvm/guestdbg.c b/arch/s390/kvm/guestdbg.c
index e97b3455d7e6..47518a324d75 100644
--- a/arch/s390/kvm/guestdbg.c
+++ b/arch/s390/kvm/guestdbg.c
@@ -473,10 +473,45 @@ static void filter_guest_per_event(struct kvm_vcpu *vcpu)
vcpu->arch.sie_block->iprcc &= ~PGM_PER;
}
+#define pssec(vcpu) (vcpu->arch.sie_block->gcr[1] & _ASCE_SPACE_SWITCH)
+#define hssec(vcpu) (vcpu->arch.sie_block->gcr[13] & _ASCE_SPACE_SWITCH)
+#define old_ssec(vcpu) ((vcpu->arch.sie_block->tecmc >> 31) & 0x1)
+#define old_as_is_home(vcpu) !(vcpu->arch.sie_block->tecmc & 0xffff)
+
void kvm_s390_handle_per_event(struct kvm_vcpu *vcpu)
{
+ int new_as;
+
if (debug_exit_required(vcpu))
vcpu->guest_debug |= KVM_GUESTDBG_EXIT_PENDING;
filter_guest_per_event(vcpu);
+
+ /*
+ * Only RP, SAC, SACF, PT, PTI, PR, PC instructions can trigger
+ * a space-switch event. PER events enforce space-switch events
+ * for these instructions. So if no PER event for the guest is left,
+ * we might have to filter the space-switch element out, too.
+ */
+ if (vcpu->arch.sie_block->iprcc == PGM_SPACE_SWITCH) {
+ vcpu->arch.sie_block->iprcc = 0;
+ new_as = psw_bits(vcpu->arch.sie_block->gpsw).as;
+
+ /*
+ * If the AS changed from / to home, we had RP, SAC or SACF
+ * instruction. Check primary and home space-switch-event
+ * controls. (theoretically home -> home produced no event)
+ */
+ if (((new_as == PSW_AS_HOME) ^ old_as_is_home(vcpu)) &&
+ (pssec(vcpu) || hssec(vcpu)))
+ vcpu->arch.sie_block->iprcc = PGM_SPACE_SWITCH;
+
+ /*
+ * PT, PTI, PR, PC instruction operate on primary AS only. Check
+ * if the primary-space-switch-event control was or got set.
+ */
+ if (new_as == PSW_AS_PRIMARY && !old_as_is_home(vcpu) &&
+ (pssec(vcpu) || old_ssec(vcpu)))
+ vcpu->arch.sie_block->iprcc = PGM_SPACE_SWITCH;
+ }
}