diff --git a/hypervisor/arch/x86/guest/vioapic.c b/hypervisor/arch/x86/guest/vioapic.c
index e5c6d7d90..736697f3c 100644
--- a/hypervisor/arch/x86/guest/vioapic.c
+++ b/hypervisor/arch/x86/guest/vioapic.c
@@ -331,13 +331,12 @@ vioapic_write(struct vioapic *vioapic, uint32_t addr, uint32_t data)
 			/* mask -> umask */
 			if ((last & IOAPIC_RTE_INTMASK) &&
 				((new & IOAPIC_RTE_INTMASK) == 0)) {
-				if ((vioapic->vm->vpic_wire_mode
-					== VPIC_WIRE_NULL) ||
-					(vioapic->vm->vpic_wire_mode
-					== VPIC_WIRE_INTR)) {
-					atomic_set_int(
-						&vioapic->vm->vpic_wire_mode,
-						VPIC_WIRE_IOAPIC);
+				if ((vioapic->vm->vpic_wire_mode ==
+						VPIC_WIRE_NULL) ||
+						(vioapic->vm->vpic_wire_mode ==
+						VPIC_WIRE_INTR)) {
+					vioapic->vm->vpic_wire_mode =
+						VPIC_WIRE_IOAPIC;
 					dev_dbg(ACRN_DBG_IOAPIC,
 						"vpic wire mode -> IOAPIC");
 				} else {
@@ -347,11 +346,10 @@ vioapic_write(struct vioapic *vioapic, uint32_t addr, uint32_t data)
 			/* unmask -> mask */
 			} else if (((last & IOAPIC_RTE_INTMASK) == 0) &&
 				(new & IOAPIC_RTE_INTMASK)) {
-				if (vioapic->vm->vpic_wire_mode
-					== VPIC_WIRE_IOAPIC) {
-					atomic_set_int(
-						&vioapic->vm->vpic_wire_mode,
-						VPIC_WIRE_INTR);
+				if (vioapic->vm->vpic_wire_mode ==
+						VPIC_WIRE_IOAPIC) {
+					vioapic->vm->vpic_wire_mode =
+						VPIC_WIRE_INTR;
 					dev_dbg(ACRN_DBG_IOAPIC,
 						"vpic wire mode -> INTR");
 				}
diff --git a/hypervisor/arch/x86/guest/vlapic.c b/hypervisor/arch/x86/guest/vlapic.c
index 1637550ea..1b3d3a9e8 100644
--- a/hypervisor/arch/x86/guest/vlapic.c
+++ b/hypervisor/arch/x86/guest/vlapic.c
@@ -528,8 +528,7 @@ vlapic_lvt_write_handler(struct vlapic *vlapic, uint32_t offset)
 		if ((last & APIC_LVT_M) && ((val & APIC_LVT_M) == 0)) {
 			if (vlapic->vm->vpic_wire_mode == VPIC_WIRE_INTR ||
 				vlapic->vm->vpic_wire_mode == VPIC_WIRE_NULL) {
-				atomic_set_int(&vlapic->vm->vpic_wire_mode,
-						VPIC_WIRE_LAPIC);
+				vlapic->vm->vpic_wire_mode = VPIC_WIRE_LAPIC;
 				dev_dbg(ACRN_DBG_LAPIC,
 					"vpic wire mode -> LAPIC");
 			} else {
@@ -539,8 +538,7 @@ vlapic_lvt_write_handler(struct vlapic *vlapic, uint32_t offset)
 		/* unmask -> mask: only from the vlapic LINT0-ExtINT enabled */
 		} else if (((last & APIC_LVT_M) == 0) && (val & APIC_LVT_M)) {
 			if (vlapic->vm->vpic_wire_mode == VPIC_WIRE_LAPIC) {
-				atomic_set_int(&vlapic->vm->vpic_wire_mode,
-						VPIC_WIRE_NULL);
+				vlapic->vm->vpic_wire_mode = VPIC_WIRE_NULL;
 				dev_dbg(ACRN_DBG_LAPIC,
 						"vpic wire mode -> NULL");
 			}
@@ -1174,8 +1172,7 @@ vlapic_svr_write_handler(struct vlapic *vlapic)
 			vlapic_mask_lvts(vlapic);
 			/* the only one enabled LINT0-ExtINT vlapic disabled */
 			if (vlapic->vm->vpic_wire_mode == VPIC_WIRE_NULL) {
-				atomic_set_int(&vlapic->vm->vpic_wire_mode,
-					 VPIC_WIRE_INTR);
+				vlapic->vm->vpic_wire_mode = VPIC_WIRE_INTR;
 				dev_dbg(ACRN_DBG_LAPIC,
 					"vpic wire mode -> INTR");
 			}
diff --git a/hypervisor/debug/uart16550.c b/hypervisor/debug/uart16550.c
index d238cda11..2409a19fb 100644
--- a/hypervisor/debug/uart16550.c
+++ b/hypervisor/debug/uart16550.c
@@ -161,10 +161,10 @@ static int uart16550_init(struct tgt_uart *tgt_uart)
 		status = -ENODEV;
 	} else {
 		if (strcmp(tgt_uart->uart_id, "STDIO") == 0) {
-			atomic_set_int(&tgt_uart->open_count, 0);
+			atomic_store_rel_int(&tgt_uart->open_count, 0);
 		} else {
 			/* set open count to 1 to prevent open */
-			atomic_set_int(&tgt_uart->open_count, 1);
+			atomic_store_rel_int(&tgt_uart->open_count, 1);
 			status = -EINVAL;
 		}
 	}