Index: sys/arm64/arm64/pmap.c
===================================================================
--- sys/arm64/arm64/pmap.c
+++ sys/arm64/arm64/pmap.c
@@ -127,6 +127,7 @@
 #include <sys/sysctl.h>
 #include <sys/_unrhdr.h>
 #include <sys/smp.h>
+#include <sys/efi.h>
 
 #include <vm/vm.h>
 #include <vm/vm_param.h>
@@ -1152,6 +1153,27 @@
  * Low level mapping routines.....
  ***************************************************/
 
+static inline int
+pmap_correct_attr(vm_paddr_t pa, int mode_req)
+{
+	uint64_t attr;
+	int mode;
+
+	/* From UEFI spec 2.8 table 7 in 2.3.6.1 */
+	attr = efi_memory_attribute(pa);
+	if ((attr & EFI_MD_ATTR_WB) != 0)
+		mode = VM_MEMATTR_WRITE_BACK;
+	else if ((attr & EFI_MD_ATTR_WT) != 0)
+		mode = VM_MEMATTR_WRITE_THROUGH;
+	else if ((attr & EFI_MD_ATTR_WC) != 0)
+		mode = VM_MEMATTR_WRITE_COMBINING;
+	else
+		mode = VM_MEMATTR_DEVICE;
+	if (mode_req < mode)
+		mode = mode_req;
+	return (mode);
+}
+
 void
 pmap_kenter(vm_offset_t sva, vm_size_t size, vm_paddr_t pa, int mode)
 {
@@ -1167,6 +1189,7 @@
 	KASSERT((size & PAGE_MASK) == 0,
 	    ("pmap_kenter: Mapping is not page-sized"));
 
+	mode = pmap_correct_attr(pa, mode);
 	attr = ATTR_DEFAULT | ATTR_IDX(mode) | L3_PAGE;
 	if (mode == DEVICE_MEMORY)
 		attr |= ATTR_XN;
@@ -4723,7 +4746,13 @@
 		/* L3 table is linked */
 		va = trunc_page(va);
 		pa = trunc_page(pa);
-		pmap_kenter(va, size, pa, CACHED_MEMORY);
+
+		/* 
+		 * Call pmap_kenter with the highest mode
+		 * it will call pmap_correct_attr to get the
+		 * correct one based on the EFI map
+		 */
+		pmap_kenter(va, size, pa, VM_MEMATTR_WRITE_BACK);
 	}
 
 	return ((void *)(va + offset));
Index: sys/arm64/include/vm.h
===================================================================
--- sys/arm64/include/vm.h
+++ sys/arm64/include/vm.h
@@ -37,7 +37,7 @@
 
 #ifdef _KERNEL
 /* If defined vmstat will try to use both of these in a switch statement */
-#define	VM_MEMATTR_WRITE_COMBINING	VM_MEMATTR_WRITE_THROUGH
+#define	VM_MEMATTR_WRITE_COMBINING	VM_MEMATTR_UNCACHEABLE
 #endif
 
 #define	VM_MEMATTR_DEFAULT	VM_MEMATTR_WRITE_BACK