KVM: s390: Fix sigp sense handling.

If sigp sense doesn't have any status bits to report, it should set
cc 0 and leave the register as-is.

Since we know about the external call pending bit, we should report
it if it is set as well.
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

arch/s390/include/asm/sigp.h

@@ -24,6 +24,7 @@
 
 #define SIGP_STATUS_CHECK_STOP		0x00000010UL
 #define SIGP_STATUS_STOPPED		0x00000040UL
+#define SIGP_STATUS_EXT_CALL_PENDING	0x00000080UL
 #define SIGP_STATUS_INVALID_PARAMETER	0x00000100UL
 #define SIGP_STATUS_INCORRECT_STATE	0x00000200UL
 #define SIGP_STATUS_NOT_RUNNING		0x00000400UL

arch/s390/kvm/sigp.c

@@ -32,12 +32,16 @@ static int __sigp_sense(struct kvm_vcpu *vcpu, u16 cpu_addr,
 	if (fi->local_int[cpu_addr] == NULL)
 		rc = SIGP_CC_NOT_OPERATIONAL;
 	else if (!(atomic_read(fi->local_int[cpu_addr]->cpuflags)
-		  & CPUSTAT_STOPPED)) {
-		*reg &= 0xffffffff00000000UL;
-		rc = SIGP_CC_STATUS_STORED;
-	} else {
+		   & (CPUSTAT_ECALL_PEND | CPUSTAT_STOPPED)))
+		rc = SIGP_CC_ORDER_CODE_ACCEPTED;
+	else {
 		*reg &= 0xffffffff00000000UL;
-		*reg |= SIGP_STATUS_STOPPED;
+		if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
+		    & CPUSTAT_ECALL_PEND)
+			*reg |= SIGP_STATUS_EXT_CALL_PENDING;
+		if (atomic_read(fi->local_int[cpu_addr]->cpuflags)
+		    & CPUSTAT_STOPPED)
+			*reg |= SIGP_STATUS_STOPPED;
 		rc = SIGP_CC_STATUS_STORED;
 	}
 	spin_unlock(&fi->lock);