From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wei Huang Subject: [PATCH 2/2] KVM: ARM64: Fix the issues when guest PMCCFILTR is configured Date: Wed, 9 Nov 2016 13:58:00 -0600 Message-ID: <1478721480-24852-2-git-send-email-wei@redhat.com> References: <1478721480-24852-1-git-send-email-wei@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A58C4401B9 for ; Wed, 9 Nov 2016 14:57:44 -0500 (EST) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9q3tcF9USj82 for ; Wed, 9 Nov 2016 14:57:43 -0500 (EST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id C711440448 for ; Wed, 9 Nov 2016 14:57:43 -0500 (EST) In-Reply-To: <1478721480-24852-1-git-send-email-wei@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: kvmarm@lists.cs.columbia.edu Cc: linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, marc.zyngier@arm.com, catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, shannon.zhao@linaro.org List-Id: kvmarm@lists.cs.columbia.edu KVM calls kvm_pmu_set_counter_event_type() when PMCCFILTR is configured. But this function can't deals with PMCCFILTR correctly because the evtCount bit of PMCCFILTR, which is reserved 0, conflits with the SW_INCR event type of other PMXEVTYPER registers. To fix it, when eventsel == 0, this function shouldn't return immediately; instead it needs to check further if select_idx is ARMV8_PMU_CYCLE_IDX. Another issue is that KVM shouldn't copy the eventsel bits of PMCCFILTER blindly to attr.config. Instead it ought to convert the request to the "cpu cycle" event type (i.e. 0x11). Signed-off-by: Wei Huang --- virt/kvm/arm/pmu.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c index 6e9c40e..69ccce3 100644 --- a/virt/kvm/arm/pmu.c +++ b/virt/kvm/arm/pmu.c @@ -305,7 +305,7 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) continue; type = vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i) & ARMV8_PMU_EVTYPE_EVENT; - if ((type == ARMV8_PMU_EVTYPE_EVENT_SW_INCR) + if ((type == ARMV8_PMUV3_PERFCTR_SW_INCR) && (enable & BIT(i))) { reg = vcpu_sys_reg(vcpu, PMEVCNTR0_EL0 + i) + 1; reg = lower_32_bits(reg); @@ -379,7 +379,8 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, eventsel = data & ARMV8_PMU_EVTYPE_EVENT; /* Software increment event does't need to be backed by a perf event */ - if (eventsel == ARMV8_PMU_EVTYPE_EVENT_SW_INCR) + if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR && + select_idx != ARMV8_PMU_CYCLE_IDX) return; memset(&attr, 0, sizeof(struct perf_event_attr)); @@ -391,7 +392,8 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, attr.exclude_kernel = data & ARMV8_PMU_EXCLUDE_EL1 ? 1 : 0; attr.exclude_hv = 1; /* Don't count EL2 events */ attr.exclude_host = 1; /* Don't count host events */ - attr.config = eventsel; + attr.config = (select_idx == ARMV8_PMU_CYCLE_IDX) ? + ARMV8_PMUV3_PERFCTR_CPU_CYCLES : eventsel; counter = kvm_pmu_get_counter_value(vcpu, select_idx); /* The initial sample period (overflow count) of an event. */ -- 2.7.4