[PATCH 06/13] arm64: KVM: VHE: Patch out kern_hyp_va
From: Marc Zyngier <hidden>
Date: 2015-07-08 16:22:21
Also in:
kvm, kvmarm, lkml
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
The kern_hyp_va macro is pretty meaninless with VHE, as there is only one mapping - the kernel one. In order to keep the code readable and efficient, use runtime patching to replace the 'and' instruction used to compute the VA with a 'nop'. Signed-off-by: Marc Zyngier <redacted> --- arch/arm64/include/asm/kvm_mmu.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index b525cd2..285642e 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h@@ -55,6 +55,8 @@ #ifdef __ASSEMBLY__ +#include <asm/alternative.h> +#include <asm/cpufeature.h> #include <asm/kvm_arm.h> .macro setup_vtcr tmp1, tmp2
@@ -69,12 +71,18 @@ msr vtcr_el2, \tmp1 isb .endm + +/* Stupid macro to deal with multiple level of macro expansion */ +.macro __vhe_nop inst val + alternative_insn "\inst\val", "nop", ARM64_HAS_VIRT_HOST_EXTN +.endm + /* * Convert a kernel VA into a HYP VA. * reg: VA to be converted. */ .macro kern_hyp_va reg - and \reg, \reg, #HYP_PAGE_OFFSET_MASK + __vhe_nop "and \reg, \reg, #", __stringify(HYP_PAGE_OFFSET_MASK) .endm #else
--
2.1.4