Commit 479428cc authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: nv: Propagate CNTHCTL_EL2.EL1NV{P,V}CT bits 



Allow a guest hypervisor to trap accesses to CNT{P,V}CT_EL02 by
propagating these trap bits to the host trap configuration.

Acked-by: default avatarOliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20241217142321.763801-10-maz@kernel.org


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent c271269e

arch/arm64/kvm/arch_timer.c

+7 −0
Original line number Diff line number Diff line
@@ -824,6 +824,10 @@ static void timer_set_traps(struct kvm_vcpu *vcpu, struct timer_map *map) 
	 * Apply the enable bits that the guest hypervisor has requested for

	 * its own guest. We can only add traps that wouldn't have been set

	 * above.

	 * Implementation choices: we do not support NV when E2H=0 in the

	 * guest, and we don't support configuration where E2H is writable

	 * by the guest (either FEAT_VHE or FEAT_E2H0 is implemented, but

	 * not both). This simplifies the handling of the EL1NV* bits.

	 */

	if (vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu)) {

		u64 val = __vcpu_sys_reg(vcpu, CNTHCTL_EL2);
@@ -834,6 +838,9 @@ static void timer_set_traps(struct kvm_vcpu *vcpu, struct timer_map *map) 


		tpt |= !(val & (CNTHCTL_EL1PCEN << 10));

		tpc |= !(val & (CNTHCTL_EL1PCTEN << 10));



		tpt02 |= (val & CNTHCTL_EL1NVPCT);

		tvt02 |= (val & CNTHCTL_EL1NVVCT);

	}



	/*