| Message ID | 20200615081954.6233-5-maz@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM/arm64: Enable PtrAuth on non-VHE KVM | expand |
On Mon, Jun 15, 2020 at 09:19:54AM +0100, Marc Zyngier wrote: > When save/restoring PtrAuth registers between host and guest, it is > pretty useless to fetch the in-memory state, while we have the right > state in the HCR_EL2 system register. Use that instead. > > Signed-off-by: Marc Zyngier <maz@kernel.org> It took me a while to spot that we switched the guest/host hcr_el2 value in the __activate_traps() and __deactivate_traps() paths, but given that this is only called in the __kvm_vcpu_run_*() paths called between those, I agree this is sound. Given that: Acked-by: Mark Rutland <mark.rutland@arm.com> Mark. > --- > arch/arm64/include/asm/kvm_ptrauth.h | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_ptrauth.h b/arch/arm64/include/asm/kvm_ptrauth.h > index 6301813dcace..f1830173fa9e 100644 > --- a/arch/arm64/include/asm/kvm_ptrauth.h > +++ b/arch/arm64/include/asm/kvm_ptrauth.h > @@ -74,7 +74,7 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF > b 1001f > alternative_else_nop_endif > 1000: > - ldr \reg1, [\g_ctxt, #(VCPU_HCR_EL2 - VCPU_CONTEXT)] > + mrs \reg1, hcr_el2 > and \reg1, \reg1, #(HCR_API | HCR_APK) > cbz \reg1, 1001f > add \reg1, \g_ctxt, #CPU_APIAKEYLO_EL1 > @@ -90,7 +90,7 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF > b 2001f > alternative_else_nop_endif > 2000: > - ldr \reg1, [\g_ctxt, #(VCPU_HCR_EL2 - VCPU_CONTEXT)] > + mrs \reg1, hcr_el2 > and \reg1, \reg1, #(HCR_API | HCR_APK) > cbz \reg1, 2001f > add \reg1, \g_ctxt, #CPU_APIAKEYLO_EL1 > -- > 2.27.0 > > _______________________________________________ > kvmarm mailing list > kvmarm@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
diff --git a/arch/arm64/include/asm/kvm_ptrauth.h b/arch/arm64/include/asm/kvm_ptrauth.h index 6301813dcace..f1830173fa9e 100644 --- a/arch/arm64/include/asm/kvm_ptrauth.h +++ b/arch/arm64/include/asm/kvm_ptrauth.h @@ -74,7 +74,7 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF b 1001f alternative_else_nop_endif 1000: - ldr \reg1, [\g_ctxt, #(VCPU_HCR_EL2 - VCPU_CONTEXT)] + mrs \reg1, hcr_el2 and \reg1, \reg1, #(HCR_API | HCR_APK) cbz \reg1, 1001f add \reg1, \g_ctxt, #CPU_APIAKEYLO_EL1 @@ -90,7 +90,7 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH_IMP_DEF b 2001f alternative_else_nop_endif 2000: - ldr \reg1, [\g_ctxt, #(VCPU_HCR_EL2 - VCPU_CONTEXT)] + mrs \reg1, hcr_el2 and \reg1, \reg1, #(HCR_API | HCR_APK) cbz \reg1, 2001f add \reg1, \g_ctxt, #CPU_APIAKEYLO_EL1
When save/restoring PtrAuth registers between host and guest, it is pretty useless to fetch the in-memory state, while we have the right state in the HCR_EL2 system register. Use that instead. Signed-off-by: Marc Zyngier <maz@kernel.org> --- arch/arm64/include/asm/kvm_ptrauth.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)