On Mon, Jun 15, 2020 at 09:19:52AM +0100, Marc Zyngier wrote: > We currently prevent PtrAuth from even being built if KVM is selected, > but VHE isn't. It is a bit of a pointless restriction, since we also > check this at run time (rejecting the enabling of PtrAuth for the > vcpu if we're not running with VHE). > > Just drop this apparently useless restriction. > > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> I can't recall exactly why we had this limitation to begin with, but given we now save/restore the keys in common hyp code, I don't see a reason to forbid this, and agree the limitation is pointless, so: Acked-by: Mark Rutland <mark.rutland@xxxxxxx> Mark. > --- > arch/arm64/Kconfig | 4 +--- > 1 file changed, 1 insertion(+), 3 deletions(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 31380da53689..d719ea9c596d 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -1516,7 +1516,6 @@ menu "ARMv8.3 architectural features" > config ARM64_PTR_AUTH > bool "Enable support for pointer authentication" > default y > - depends on !KVM || ARM64_VHE > depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC > # GCC 9.1 and later inserts a .note.gnu.property section note for PAC > # which is only understood by binutils starting with version 2.33.1. > @@ -1543,8 +1542,7 @@ config ARM64_PTR_AUTH > > The feature is detected at runtime. If the feature is not present in > hardware it will not be advertised to userspace/KVM guest nor will it > - be enabled. However, KVM guest also require VHE mode and hence > - CONFIG_ARM64_VHE=y option to use this feature. > + be enabled. > > If the feature is present on the boot CPU but not on a late CPU, then > the late CPU will be parked. Also, if the boot CPU does not have > -- > 2.27.0 > > _______________________________________________ > kvmarm mailing list > kvmarm@xxxxxxxxxxxxxxxxxxxxx > https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
