diff --git a/sys/mips/cavium/octeon_mp.c b/sys/mips/cavium/octeon_mp.c
index a0eae2c095f9..34de442eedba 100644
--- a/sys/mips/cavium/octeon_mp.c
+++ b/sys/mips/cavium/octeon_mp.c
@@ -96,7 +96,7 @@ platform_init_ap(int cpuid)
 	 */
 	clock_int_mask = hard_int_mask(5);
 	ipi_int_mask = hard_int_mask(platform_ipi_intrnum());
-	set_intr_mask(MIPS_SR_INT_MASK & ~(ipi_int_mask | clock_int_mask));
+	set_intr_mask(ipi_int_mask | clock_int_mask);
 
 	mips_wbflush();
 }
diff --git a/sys/mips/include/cpufunc.h b/sys/mips/include/cpufunc.h
index efaa3f4f94b1..a1715c9fdf48 100644
--- a/sys/mips/include/cpufunc.h
+++ b/sys/mips/include/cpufunc.h
@@ -272,7 +272,7 @@ set_intr_mask(uint32_t mask)
 	uint32_t ostatus;
 
 	ostatus = mips_rd_status();
-	mask = (ostatus & ~MIPS_SR_INT_MASK) | (~mask & MIPS_SR_INT_MASK);
+	mask = (ostatus & ~MIPS_SR_INT_MASK) | (mask & MIPS_SR_INT_MASK);
 	mips_wr_status(mask);
 	return (ostatus);
 }
diff --git a/sys/mips/mips/machdep.c b/sys/mips/mips/machdep.c
index 8c16051f3ad3..120fde7a7923 100644
--- a/sys/mips/mips/machdep.c
+++ b/sys/mips/mips/machdep.c
@@ -356,7 +356,7 @@ mips_vector_init(void)
 	 * Mask all interrupts. Each interrupt will be enabled
 	 * when handler is installed for it
 	 */
-	set_intr_mask(MIPS_SR_INT_MASK);
+	set_intr_mask(0);
 
 	/* Clear BEV in SR so we start handling our own exceptions */
 	mips_wr_status(mips_rd_status() & ~MIPS_SR_BEV);
diff --git a/sys/mips/mips/trap.c b/sys/mips/mips/trap.c
index 2323c6688824..009db7caed60 100644
--- a/sys/mips/mips/trap.c
+++ b/sys/mips/mips/trap.c
@@ -304,7 +304,7 @@ trap(struct trapframe *trapframe)
 	 * return to userland.
 	 */
 	if (trapframe->sr & MIPS_SR_INT_IE) {
-		set_intr_mask(~(trapframe->sr & MIPS_SR_INT_MASK));
+		set_intr_mask(trapframe->sr & MIPS_SR_INT_MASK);
 		intr_enable();
 	} else {
 		intr_disable();
diff --git a/sys/mips/sibyte/sb_machdep.c b/sys/mips/sibyte/sb_machdep.c
index 45f39e8c99b7..ba4b62e95a6d 100644
--- a/sys/mips/sibyte/sb_machdep.c
+++ b/sys/mips/sibyte/sb_machdep.c
@@ -370,7 +370,7 @@ platform_init_ap(int cpuid)
 	 */
 	clock_int_mask = hard_int_mask(5);
 	ipi_int_mask = hard_int_mask(platform_ipi_intrnum());
-	set_intr_mask(MIPS_SR_INT_MASK & ~(ipi_int_mask | clock_int_mask));
+	set_intr_mask(ipi_int_mask | clock_int_mask);
 }
 
 int