:: commit 0ad8f9b5adfcf99ed8a14451d90810c5357b33d6

diff --git a/PROTOCOL.md b/PROTOCOL.md
index 8a0b96fa..0319ecbd 100644
--- a/PROTOCOL.md
+++ b/PROTOCOL.md
@@ -114,14 +114,18 @@ config).
 
 ### x86_64
 
-All HHDM memory regions are mapped using write-back (WB) caching, except
-framebuffer regions which are mapped using write-combining (WC) caching.
+The kernel executable, loaded at or above `0xffffffff80000000`, see all of its
+segments mapped using write-back (WB) caching at the page tables level.
 
-The MTRRs are left as the firmware set them up.
+All HHDM memory regions are mapped using write-back (WB) caching at the page
+tables level, except framebuffer regions which are mapped using write-combining
+(WC) caching at the page tables level.
 
 The PAT's (Page Attribute Table) layout is unspecified and the OS should
 not be making assumptions about it.
 
+The MTRRs are left as the firmware set them up.
+
 ### aarch64
 
 All HHDM memory regions are mapped using the Normal Write-Back RW-Allocate