diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index e7a58e81f7a6fbdfd1992a5e2f96d4253a1927ba..2b1e1409bfa6f1f7a89ec95f60197927ec6f0036 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -715,7 +715,7 @@ static void s390_pcihost_hot_plug(HotplugHandler *hotplug_dev,
         pbdev->pdev = pdev;
         pbdev->iommu = s390_pci_get_iommu(s, pdev->bus, pdev->devfn);
         pbdev->iommu->pbdev = pbdev;
-        pbdev->state = ZPCI_FS_STANDBY;
+        pbdev->state = ZPCI_FS_DISABLED;
 
         if (s390_pci_msix_init(pbdev)) {
             error_setg(errp, "MSI-X support is mandatory "
diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index dee72a787d4c5c1fdd97da9fe8b21d3cb5a54efd..85d0a6c3aff7f2c735e6a2891dfabe3856c8056d 100644
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -3432,6 +3432,7 @@ static ExitStatus op_risbg(DisasContext *s, DisasOps *o)
     /* Adjust the arguments for the specific insn.  */
     switch (s->fields->op2) {
     case 0x55: /* risbg */
+    case 0x59: /* risbgn */
         i3 &= 63;
         i4 &= 63;
         pmask = ~0;
@@ -3447,7 +3448,7 @@ static ExitStatus op_risbg(DisasContext *s, DisasOps *o)
         pmask = 0x00000000ffffffffull;
         break;
     default:
-        abort();
+        g_assert_not_reached();
     }
 
     /* MASK is the set of bits to be inserted from R2.
@@ -3464,11 +3465,7 @@ static ExitStatus op_risbg(DisasContext *s, DisasOps *o)
        insns, we need to keep the other half of the register.  */
     imask = ~mask | ~pmask;
     if (do_zero) {
-        if (s->fields->op2 == 0x55) {
-            imask = 0;
-        } else {
-            imask = ~pmask;
-        }
+        imask = ~pmask;
     }
 
     len = i4 - i3 + 1;