Commit 892f7c38 authored by Marc Zyngier's avatar Marc Zyngier
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KVM: arm64: Fix WFxT handling of nested virt 



The spec for WFxT indicates that the parameter to the WFxT instruction
is relative to the reading of CNTVCT_EL0. This means that the implementation
needs to take the execution context into account, as CNTVOFF_EL2
does not always affect readings of CNTVCT_EL0 (such as when HCR_EL2.E2H
is 1 and that we're in host context).

This also rids us of the last instance of KVM_REG_ARM_TIMER_CNT
outside of the userspace interaction code.

Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent c3be3a48

arch/arm64/kvm/handle_exit.c

+6 −1
Original line number Diff line number Diff line
@@ -147,7 +147,12 @@ static int kvm_handle_wfx(struct kvm_vcpu *vcpu) 
		if (esr & ESR_ELx_WFx_ISS_RV) {

			u64 val, now;



			now = kvm_arm_timer_get_reg(vcpu, KVM_REG_ARM_TIMER_CNT);

			now = kvm_phys_timer_read();

			if (is_hyp_ctxt(vcpu) && vcpu_el2_e2h_is_set(vcpu))

				now -= timer_get_offset(vcpu_hvtimer(vcpu));

			else

				now -= timer_get_offset(vcpu_vtimer(vcpu));



			val = vcpu_get_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu));



			if (now >= val)