arm64: KVM: document kernel object mappings in HYP
HYP mode has access to some of the kernel pages. Document the
memory mapping and the offset between kernel VA and HYP VA.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/Documentation/arm64/memory.txt b/Documentation/arm64/memory.txt
index 5f583af..78a37712 100644
--- a/Documentation/arm64/memory.txt
+++ b/Documentation/arm64/memory.txt
@@ -73,3 +73,10 @@
| | +--------------------------> [41:29] L2 index (only 38:29 used)
| +-------------------------------> [47:42] L1 index (not used)
+-------------------------------------------------> [63] TTBR0/1
+
+When using KVM, the hypervisor maps kernel pages in EL2, at a fixed
+offset from the kernel VA (top 24bits of the kernel VA set to zero):
+
+Start End Size Use
+-----------------------------------------------------------------------
+0000004000000000 0000007fffffffff 256GB kernel objects mapped in HYP
