summaryrefslogtreecommitdiff
path: root/arch/arm64/include/asm/kvm_mmu.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm64/include/asm/kvm_mmu.h')
-rw-r--r--arch/arm64/include/asm/kvm_mmu.h14
1 files changed, 12 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 736433912a1e..22732a5e3119 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -23,13 +23,16 @@
#include <asm/cpufeature.h>
/*
- * As we only have the TTBR0_EL2 register, we cannot express
+ * As ARMv8.0 only has the TTBR0_EL2 register, we cannot express
* "negative" addresses. This makes it impossible to directly share
* mappings with the kernel.
*
* Instead, give the HYP mode its own VA region at a fixed offset from
* the kernel by just masking the top bits (which are all ones for a
* kernel address).
+ *
+ * ARMv8.1 (using VHE) does have a TTBR1_EL2, and doesn't use these
+ * macros (the entire kernel runs at EL2).
*/
#define HYP_PAGE_OFFSET_SHIFT VA_BITS
#define HYP_PAGE_OFFSET_MASK ((UL(1) << HYP_PAGE_OFFSET_SHIFT) - 1)
@@ -56,12 +59,19 @@
#ifdef __ASSEMBLY__
+#include <asm/alternative.h>
+#include <asm/cpufeature.h>
+
/*
* Convert a kernel VA into a HYP VA.
* reg: VA to be converted.
*/
.macro kern_hyp_va reg
+alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
and \reg, \reg, #HYP_PAGE_OFFSET_MASK
+alternative_else
+ nop
+alternative_endif
.endm
#else
@@ -307,7 +317,7 @@ static inline unsigned int kvm_get_vmid_bits(void)
{
int reg = read_system_reg(SYS_ID_AA64MMFR1_EL1);
- return (cpuid_feature_extract_field(reg, ID_AA64MMFR1_VMIDBITS_SHIFT) == 2) ? 16 : 8;
+ return (cpuid_feature_extract_unsigned_field(reg, ID_AA64MMFR1_VMIDBITS_SHIFT) == 2) ? 16 : 8;
}
#endif /* __ASSEMBLY__ */