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| author |   Mark Rutland <mark.rutland@arm.com> | 2018-12-07 18:39:23 +0000 |
|---|---|---|
| committer |   Will Deacon <will.deacon@arm.com> | 2018-12-13 16:42:46 +0000 |
| commit | b3669b1e1c09890d61109a1a8ece2c5b66804714 (patch) | |
| tree | bd074970ea128e8151e2fd3406f8041252777152 | |
| parent | arm64/kvm: hide ptrauth from guests (diff) | |
| download | linux-dev-b3669b1e1c09890d61109a1a8ece2c5b66804714.tar.xz linux-dev-b3669b1e1c09890d61109a1a8ece2c5b66804714.zip | |
arm64: Don't trap host pointer auth use to EL2
To allow EL0 (and/or EL1) to use pointer authentication functionality,
we must ensure that pointer authentication instructions and accesses to
pointer authentication keys are not trapped to EL2.
This patch ensures that HCR_EL2 is configured appropriately when the
kernel is booted at EL2. For non-VHE kernels we set HCR_EL2.{API,APK},
ensuring that EL1 can access keys and permit EL0 use of instructions.
For VHE kernels host EL0 (TGE && E2H) is unaffected by these settings,
and it doesn't matter how we configure HCR_EL2.{API,APK}, so we don't
bother setting them.
This does not enable support for KVM guests, since KVM manages HCR_EL2
itself when running VMs.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Will Deacon <will.deacon@arm.com>
| -rw-r--r-- | arch/arm64/include/asm/kvm_arm.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/kvm_arm.h b/arch/arm64/include/asm/kvm_arm.h index c8825c5a8dd0..f9123fe8fcf3 100644 --- a/arch/arm64/include/asm/kvm_arm.h +++ b/arch/arm64/include/asm/kvm_arm.h @@ -24,6 +24,8 @@ /* Hyp Configuration Register (HCR) bits */ #define HCR_FWB (UL(1) << 46) +#define HCR_API (UL(1) << 41) +#define HCR_APK (UL(1) << 40) #define HCR_TEA (UL(1) << 37) #define HCR_TERR (UL(1) << 36) #define HCR_TLOR (UL(1) << 35) @@ -87,7 +89,7 @@ HCR_AMO | HCR_SWIO | HCR_TIDCP | HCR_RW | HCR_TLOR | \ HCR_FMO | HCR_IMO) #define HCR_VIRT_EXCP_MASK (HCR_VSE | HCR_VI | HCR_VF) -#define HCR_HOST_NVHE_FLAGS (HCR_RW) +#define HCR_HOST_NVHE_FLAGS (HCR_RW | HCR_API | HCR_APK) #define HCR_HOST_VHE_FLAGS (HCR_RW | HCR_TGE | HCR_E2H) /* TCR_EL2 Registers bits */ |