On Fri, Dec 20, 2019 at 02:30:18PM +0000, Andrew Murray wrote: > As we now save/restore the profiler state there is no need to trap > accesses to the statistical profiling controls. Let's unset the > _TPMS bit. > > Signed-off-by: Andrew Murray <andrew.murray@xxxxxxx> > --- > arch/arm64/kvm/debug.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c > index 43487f035385..07ca783e7d9e 100644 > --- a/arch/arm64/kvm/debug.c > +++ b/arch/arm64/kvm/debug.c > @@ -88,7 +88,6 @@ void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) > * - Performance monitors (MDCR_EL2_TPM/MDCR_EL2_TPMCR) > * - Debug ROM Address (MDCR_EL2_TDRA) > * - OS related registers (MDCR_EL2_TDOSA) > - * - Statistical profiler (MDCR_EL2_TPMS/MDCR_EL2_E2PB) > * > * Additionally, KVM only traps guest accesses to the debug registers if > * the guest is not actively using them (see the KVM_ARM64_DEBUG_DIRTY > @@ -111,7 +110,6 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) > */ > vcpu->arch.mdcr_el2 = __this_cpu_read(mdcr_el2) & MDCR_EL2_HPMN_MASK; > vcpu->arch.mdcr_el2 |= (MDCR_EL2_TPM | > - MDCR_EL2_TPMS | > MDCR_EL2_TPMCR | > MDCR_EL2_TDRA | > MDCR_EL2_TDOSA); I think that this should be conditional on some vcpu feature flag. If nothing else, this could break existing migration cases otherwise. Thanks, Mark.
