arm64: Small fixes extracted from larger MMU fixup.

* User-Execute without User-Read mapping is disallowed. * Add comments to arch_vm_set_memory_type Change-Id: I450206ab973552dc36a7d778f573154541fd709f Reviewed-on: https://review.haiku-os.org/c/haiku/+/8098 Reviewed-by: waddlesplash <[email protected]>
2024-08-24 02:32:33 +00:00
parent 87c4aa1308
commit 087c7dd654
1 changed files with 8 additions and 0 deletions
@@ -109,6 +109,12 @@ arch_vm_supports_protection(uint32 protection)
 		return false;
 	}

+	// User-Execute implies User-Read, because it would break PAN otherwise
+	if ((protection & B_EXECUTE_AREA) != 0
+	    && (protection & B_READ_AREA) == 0) {
+		return false;
+	}
+
 	return true;
 }

@@ -122,5 +128,7 @@ arch_vm_unset_memory_type(VMArea* area)
 status_t
 arch_vm_set_memory_type(VMArea* area, phys_addr_t physicalBase, uint32 type)
 {
+	// Memory type is set in page tables during mapping,
+	// no need to do anything more here.
 	return B_OK;
 }