summaryrefslogtreecommitdiff
path: root/arch/arm64
diff options
context:
space:
mode:
authorVladimir Murzin <vladimir.murzin@arm.com>2018-07-31 14:08:57 +0100
committerCatalin Marinas <catalin.marinas@arm.com>2018-09-18 12:03:34 +0100
commitab510027dc4dbd1eeb611a34b0cda8b21fcde492 (patch)
tree6f71d3b509e910de4db2cebd1b76f33ef11873b7 /arch/arm64
parent5ffdfaedfa0aba3f5db0fbb8ed4f3192be2b39b8 (diff)
arm64: KVM: Enable Common Not Private translations
We rely on cpufeature framework to detect and enable CNP so for KVM we need to patch hyp to set CNP bit just before TTBR0_EL2 gets written. For the guest we encode CNP bit while building vttbr, so we don't need to bother with that in a world switch. Reviewed-by: James Morse <james.morse@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64')
-rw-r--r--arch/arm64/include/asm/kvm_arm.h1
-rw-r--r--arch/arm64/include/asm/kvm_mmu.h5
-rw-r--r--arch/arm64/kvm/hyp-init.S3
3 files changed, 9 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h
index aa45df752a16..b476bc46f0ab 100644
--- a/arch/arm64/include/asm/kvm_arm.h
+++ b/arch/arm64/include/asm/kvm_arm.h
@@ -175,6 +175,7 @@
#define VTCR_EL2_FLAGS (VTCR_EL2_COMMON_BITS | VTCR_EL2_TGRAN_FLAGS)
#define VTTBR_X (VTTBR_X_TGRAN_MAGIC - VTCR_EL2_T0SZ_IPA)
+#define VTTBR_CNP_BIT (UL(1))
#define VTTBR_BADDR_MASK (((UL(1) << (PHYS_MASK_SHIFT - VTTBR_X)) - 1) << VTTBR_X)
#define VTTBR_VMID_SHIFT (UL(48))
#define VTTBR_VMID_MASK(size) (_AT(u64, (1 << size) - 1) << VTTBR_VMID_SHIFT)
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index d6fff7de5539..64337afbf124 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -517,5 +517,10 @@ static inline int hyp_map_aux_data(void)
#define kvm_phys_to_vttbr(addr) phys_to_ttbr(addr)
+static inline bool kvm_cpu_has_cnp(void)
+{
+ return system_supports_cnp();
+}
+
#endif /* __ASSEMBLY__ */
#endif /* __ARM64_KVM_MMU_H__ */
diff --git a/arch/arm64/kvm/hyp-init.S b/arch/arm64/kvm/hyp-init.S
index ea9225160786..4576b86a5579 100644
--- a/arch/arm64/kvm/hyp-init.S
+++ b/arch/arm64/kvm/hyp-init.S
@@ -65,6 +65,9 @@ __do_hyp_init:
b.lo __kvm_handle_stub_hvc
phys_to_ttbr x4, x0
+alternative_if ARM64_HAS_CNP
+ orr x4, x4, #TTBR_CNP_BIT
+alternative_else_nop_endif
msr ttbr0_el2, x4
mrs x4, tcr_el1