lkml.org 
[lkml]   [2018]   [Dec]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v6 05/13] arm64: Don't trap host pointer auth use to EL2
From
Date
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 <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
> ---
> arch/arm64/include/asm/kvm_arm.h | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)

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


r~

\
 
 \ /
  Last update: 2018-12-09 15:55    [W:0.172 / U:0.384 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site