Commit 719f5206 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: nv: Add kvm_has_pauth() helper 



Pointer Authentication comes in many flavors, and a faithful emulation
relies on correctly handling the flavour implemented by the HW.

For this, provide a new kvm_has_pauth() that checks whether we
expose to the guest a particular level of support. This checks
across all 3 possible authentication algorithms (Q5, Q3 and IMPDEF).

Reviewed-by: default avatarOliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240419102935.1935571-12-maz@kernel.org


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent 15db0347

arch/arm64/include/asm/kvm_host.h

+15 −0
Original line number Diff line number Diff line
@@ -1336,4 +1336,19 @@ bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu); 
	(get_idreg_field((kvm), id, fld) >= expand_field_sign(id, fld, min) && \

	 get_idreg_field((kvm), id, fld) <= expand_field_sign(id, fld, max))



/* Check for a given level of PAuth support */

#define kvm_has_pauth(k, l)						\

	({								\

		bool pa, pi, pa3;					\

									\

		pa  = kvm_has_feat((k), ID_AA64ISAR1_EL1, APA, l);	\

		pa &= kvm_has_feat((k), ID_AA64ISAR1_EL1, GPA, IMP);	\

		pi  = kvm_has_feat((k), ID_AA64ISAR1_EL1, API, l);	\

		pi &= kvm_has_feat((k), ID_AA64ISAR1_EL1, GPI, IMP);	\

		pa3  = kvm_has_feat((k), ID_AA64ISAR2_EL1, APA3, l);	\

		pa3 &= kvm_has_feat((k), ID_AA64ISAR2_EL1, GPA3, IMP);	\

									\

		(pa + pi + pa3) == 1;					\

	})



#endif /* __ARM64_KVM_HOST_H__ */