Commit d3ba35b6 authored by Oliver Upton's avatar Oliver Upton
Browse files

KVM: arm64: nv: Reload PMU events upon MDCR_EL2.HPME change 



MDCR_EL2.HPME is the 'global' enable bit for event counters reserved for
EL2. Give the PMU a kick when it's changed to ensure events are
reprogrammed before returning to the guest.

Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241217175550.3658212-1-oliver.upton@linux.dev


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent adf8623b

arch/arm64/kvm/sys_regs.c

+21 −1
Original line number Diff line number Diff line
@@ -2448,6 +2448,26 @@ static unsigned int s1pie_el2_visibility(const struct kvm_vcpu *vcpu, 
	return __el2_visibility(vcpu, rd, s1pie_visibility);

}



static bool access_mdcr(struct kvm_vcpu *vcpu,

			struct sys_reg_params *p,

			const struct sys_reg_desc *r)

{

	u64 old = __vcpu_sys_reg(vcpu, MDCR_EL2);



	if (!access_rw(vcpu, p, r))

		return false;



	/*

	 * Request a reload of the PMU to enable/disable the counters affected

	 * by HPME.

	 */

	if ((old ^ __vcpu_sys_reg(vcpu, MDCR_EL2)) & MDCR_EL2_HPME)

		kvm_make_request(KVM_REQ_RELOAD_PMU, vcpu);



	return true;

}





/*

 * Architected system registers.

 * Important: Must be sorted ascending by Op0, Op1, CRn, CRm, Op2
@@ -2981,7 +3001,7 @@ static const struct sys_reg_desc sys_reg_descs[] = { 
	EL2_REG(SCTLR_EL2, access_rw, reset_val, SCTLR_EL2_RES1),

	EL2_REG(ACTLR_EL2, access_rw, reset_val, 0),

	EL2_REG_VNCR(HCR_EL2, reset_hcr, 0),

	EL2_REG(MDCR_EL2, access_rw, reset_val, 0),

	EL2_REG(MDCR_EL2, access_mdcr, reset_val, 0),

	EL2_REG(CPTR_EL2, access_rw, reset_val, CPTR_NVHE_EL2_RES1),

	EL2_REG_VNCR(HSTR_EL2, reset_val, 0),

	EL2_REG_VNCR(HFGRTR_EL2, reset_val, 0),