diff --git a/hw/misc/mos6522.c b/hw/misc/mos6522.c
index 44eb306cf1..ad5041d8c0 100644
--- a/hw/misc/mos6522.c
+++ b/hw/misc/mos6522.c
@@ -241,7 +241,7 @@ uint64_t mos6522_read(void *opaque, hwaddr addr, unsigned size)
         break;
     case VIA_REG_SR:
         val = s->sr;
-        s->ifr &= ~(SR_INT | CB1_INT | CB2_INT);
+        s->ifr &= ~SR_INT;
         mos6522_update_irq(s);
         break;
     case VIA_REG_ACR: