diff --git a/zephyr/lib/vregion.c b/zephyr/lib/vregion.c
index 9c8c94c23f97..4cc2437fcec4 100644
--- a/zephyr/lib/vregion.c
+++ b/zephyr/lib/vregion.c
@@ -127,8 +127,11 @@ struct vregion *vregion_create(size_t memsize)
 	 */
 	total_size = ALIGN_UP(memsize, CONFIG_MM_DRV_PAGE_SIZE);
 
-	/* allocate vregion metadata separately to keep it inaccessible to the user */
-	vr = rmalloc(0, sizeof(*vr));
+	/* allocate vregion metadata separately to keep it inaccessible to the user.
+	 * Use coherent memory so interim heap state written on one core is
+	 * visible to other cores during cross-core buffer allocation.
+	 */
+	vr = rmalloc(SOF_MEM_FLAG_COHERENT, sizeof(*vr));
 	if (!vr)
 		return NULL;
 
@@ -254,6 +257,11 @@ static void interim_heap_init(struct vregion *vr)
 	k_heap_init(&vr->interim.heap, interim_base, interim_size);
 	vr->type = VREGION_MEM_TYPE_INTERIM;
 
+	/* Flush the heap metadata written by k_heap_init to main memory
+	 * so other cores can access the interim heap without stale cache.
+	 */
+	sys_cache_data_flush_range(interim_base, interim_size);
+
 	/* Update lifetime heap with the interim heap usage. */
 	vr->lifetime.ptr = (void *)(interim_base + interim_size);
 	vr->lifetime.used = (uint8_t *)vr->lifetime.ptr - (uint8_t *)vr->lifetime.base;