diff --git a/sys/amd64/amd64/mp_machdep.c b/sys/amd64/amd64/mp_machdep.c
index 79fc383a5e11..945a588369b0 100644
--- a/sys/amd64/amd64/mp_machdep.c
+++ b/sys/amd64/amd64/mp_machdep.c
@@ -1593,7 +1593,7 @@ undirect_isa_irq(int rirq)
 	if (bootverbose)
 	    printf("Freeing redirected ISA irq %d.\n", rirq);
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 	    printf("Freeing (NOT implemented) redirected ISA irq %d.\n", rirq);
@@ -1613,7 +1613,7 @@ undirect_pci_irq(int rirq)
 		printf("Freeing redirected PCI irq %d.\n", rirq);
 
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 		printf("Freeing (NOT implemented) redirected PCI irq %d.\n",
diff --git a/sys/amd64/amd64/mptable.c b/sys/amd64/amd64/mptable.c
index 79fc383a5e11..945a588369b0 100644
--- a/sys/amd64/amd64/mptable.c
+++ b/sys/amd64/amd64/mptable.c
@@ -1593,7 +1593,7 @@ undirect_isa_irq(int rirq)
 	if (bootverbose)
 	    printf("Freeing redirected ISA irq %d.\n", rirq);
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 	    printf("Freeing (NOT implemented) redirected ISA irq %d.\n", rirq);
@@ -1613,7 +1613,7 @@ undirect_pci_irq(int rirq)
 		printf("Freeing redirected PCI irq %d.\n", rirq);
 
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 		printf("Freeing (NOT implemented) redirected PCI irq %d.\n",
diff --git a/sys/amd64/include/mptable.h b/sys/amd64/include/mptable.h
index 79fc383a5e11..945a588369b0 100644
--- a/sys/amd64/include/mptable.h
+++ b/sys/amd64/include/mptable.h
@@ -1593,7 +1593,7 @@ undirect_isa_irq(int rirq)
 	if (bootverbose)
 	    printf("Freeing redirected ISA irq %d.\n", rirq);
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 	    printf("Freeing (NOT implemented) redirected ISA irq %d.\n", rirq);
@@ -1613,7 +1613,7 @@ undirect_pci_irq(int rirq)
 		printf("Freeing redirected PCI irq %d.\n", rirq);
 
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 		printf("Freeing (NOT implemented) redirected PCI irq %d.\n",
diff --git a/sys/i386/i386/mp_machdep.c b/sys/i386/i386/mp_machdep.c
index 79fc383a5e11..945a588369b0 100644
--- a/sys/i386/i386/mp_machdep.c
+++ b/sys/i386/i386/mp_machdep.c
@@ -1593,7 +1593,7 @@ undirect_isa_irq(int rirq)
 	if (bootverbose)
 	    printf("Freeing redirected ISA irq %d.\n", rirq);
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 	    printf("Freeing (NOT implemented) redirected ISA irq %d.\n", rirq);
@@ -1613,7 +1613,7 @@ undirect_pci_irq(int rirq)
 		printf("Freeing redirected PCI irq %d.\n", rirq);
 
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 		printf("Freeing (NOT implemented) redirected PCI irq %d.\n",
diff --git a/sys/i386/i386/mptable.c b/sys/i386/i386/mptable.c
index 79fc383a5e11..945a588369b0 100644
--- a/sys/i386/i386/mptable.c
+++ b/sys/i386/i386/mptable.c
@@ -1593,7 +1593,7 @@ undirect_isa_irq(int rirq)
 	if (bootverbose)
 	    printf("Freeing redirected ISA irq %d.\n", rirq);
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 	    printf("Freeing (NOT implemented) redirected ISA irq %d.\n", rirq);
@@ -1613,7 +1613,7 @@ undirect_pci_irq(int rirq)
 		printf("Freeing redirected PCI irq %d.\n", rirq);
 
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 		printf("Freeing (NOT implemented) redirected PCI irq %d.\n",
diff --git a/sys/i386/include/mptable.h b/sys/i386/include/mptable.h
index 79fc383a5e11..945a588369b0 100644
--- a/sys/i386/include/mptable.h
+++ b/sys/i386/include/mptable.h
@@ -1593,7 +1593,7 @@ undirect_isa_irq(int rirq)
 	if (bootverbose)
 	    printf("Freeing redirected ISA irq %d.\n", rirq);
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 	    printf("Freeing (NOT implemented) redirected ISA irq %d.\n", rirq);
@@ -1613,7 +1613,7 @@ undirect_pci_irq(int rirq)
 		printf("Freeing redirected PCI irq %d.\n", rirq);
 
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 		printf("Freeing (NOT implemented) redirected PCI irq %d.\n",
diff --git a/sys/kern/subr_smp.c b/sys/kern/subr_smp.c
index 79fc383a5e11..945a588369b0 100644
--- a/sys/kern/subr_smp.c
+++ b/sys/kern/subr_smp.c
@@ -1593,7 +1593,7 @@ undirect_isa_irq(int rirq)
 	if (bootverbose)
 	    printf("Freeing redirected ISA irq %d.\n", rirq);
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 	    printf("Freeing (NOT implemented) redirected ISA irq %d.\n", rirq);
@@ -1613,7 +1613,7 @@ undirect_pci_irq(int rirq)
 		printf("Freeing redirected PCI irq %d.\n", rirq);
 
 	/** FIXME: tickle the MB redirector chip */
-	return ???;
+	return -1;
 #else
 	if (bootverbose)
 		printf("Freeing (NOT implemented) redirected PCI irq %d.\n",