From 9339fd348dd98ed64879a48dc7290cc3fa4e2911 Mon Sep 17 00:00:00 2001 From: Yury Norov Date: Wed, 13 Sep 2017 21:08:30 +0300 Subject: [PATCH] arm64: fix documentation on kernel pages mappings to HYP VA The Documentation/arm64/memory.txt says: 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): In fact, kernel addresses are transleted to HYP with kern_hyp_va macro, which has more options, and none of them assumes clearing of top 24bits of the kernel VA. Acked-by: Marc Zyngier Signed-off-by: Yury Norov [will: removed gory details] Signed-off-by: Will Deacon --- Documentation/arm64/memory.txt | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/Documentation/arm64/memory.txt b/Documentation/arm64/memory.txt index d7273a5f6456..671bc0639262 100644 --- a/Documentation/arm64/memory.txt +++ b/Documentation/arm64/memory.txt @@ -86,9 +86,9 @@ Translation table lookup with 64KB pages: +-------------------------------------------------> [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): +When using KVM without the Virtualization Host Extensions, the hypervisor +maps kernel pages in EL2 at a fixed offset from the kernel VA. See the +kern_hyp_va macro for more details. -Start End Size Use ------------------------------------------------------------------------ -0000004000000000 0000007fffffffff 256GB kernel objects mapped in HYP +When using KVM with the Virtualization Host Extensions, no additional +mappings are created, since the host kernel runs directly in EL2.