On 12/7/18 12:39 PM, Kristina Martsenko wrote:

From: Mark Rutland <mark.rutland@arm.com>

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.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kristina Martsenko <redacted>
Acked-by: Christoffer Dall <redacted>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <redacted>
Cc: Will Deacon <redacted>
Cc: kvmarm@lists.cs.columbia.edu
---
 arch/arm64/include/asm/kvm_arm.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>


r~

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