diff --git a/sys/dev/ahci/ahci.c b/sys/dev/ahci/ahci.c
index ec42b3c1f54b..a1406f60b7b0 100644
--- a/sys/dev/ahci/ahci.c
+++ b/sys/dev/ahci/ahci.c
@@ -416,7 +416,8 @@ ahci_setup_interrupt(device_t dev)
 		else if (ctlr->numirqs == 1 || i >= ctlr->channels ||
 		    (ctlr->ccc && i == ctlr->cccv))
 			ctlr->irqs[i].mode = AHCI_IRQ_MODE_ALL;
-		else if (i == ctlr->numirqs - 1)
+		else if (ctlr->channels > ctlr->numirqs &&
+		    i == ctlr->numirqs - 1)
 			ctlr->irqs[i].mode = AHCI_IRQ_MODE_AFTER;
 		else
 			ctlr->irqs[i].mode = AHCI_IRQ_MODE_ONE;