[PATCH 22/23] KVM: arm64: pmu: Only handle supported event counters

From: Marc Zyngier <maz@kernel.org>
To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alexandru Elisei <alexandru.elisei@arm.com>,
	Andrew Jones <drjones@redhat.com>,
	Andrew Murray <andrew.murray@arm.com>,
	Beata Michalska <beata.michalska@linaro.org>,
	Christoffer Dall <christoffer.dall@arm.com>,
	Eric Auger <eric.auger@redhat.com>, Gavin Shan <gshan@redhat.com>,
	Haibin Wang <wanghaibin.wang@huawei.com>,
	James Morse <james.morse@arm.com>,
	Mark Brown <broonie@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Russell King <rmk+kernel@armlinux.org.uk>,
	Shannon Zhao <shannon.zhao@linux.alibaba.com>,
	Steven Price <steven.price@arm.com>,
	Will Deacon <will@kernel.org>, YueHaibing <yuehaibing@huawei.com>,
	Zenghui Yu <yuzenghui@huawei.com>,
	Julien Thierry <julien.thierry.kdev@gmail.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	linux-arm-kernel@lists.infradead.org,
	kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org
Subject: [PATCH 22/23] KVM: arm64: pmu: Only handle supported event counters
Date: Thu, 30 Jan 2020 13:25:57 +0000	[thread overview]
Message-ID: <20200130132558.10201-23-maz@kernel.org> (raw)
In-Reply-To: <20200130132558.10201-1-maz@kernel.org>

From: Eric Auger <eric.auger@redhat.com>

Let the code never use unsupported event counters. Change
kvm_pmu_handle_pmcr() to only reset supported counters and
kvm_pmu_vcpu_reset() to only stop supported counters.

Other actions are filtered on the supported counters in
kvm/sysregs.c

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200124142535.29386-5-eric.auger@redhat.com
---
 virt/kvm/arm/pmu.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
index 560db6282137..f0d0312c0a55 100644
--- a/virt/kvm/arm/pmu.c
+++ b/virt/kvm/arm/pmu.c
@@ -247,10 +247,11 @@ void kvm_pmu_vcpu_init(struct kvm_vcpu *vcpu)
  */
 void kvm_pmu_vcpu_reset(struct kvm_vcpu *vcpu)
 {
-	int i;
+	unsigned long mask = kvm_pmu_valid_counter_mask(vcpu);
 	struct kvm_pmu *pmu = &vcpu->arch.pmu;
+	int i;
 
-	for (i = 0; i < ARMV8_PMU_MAX_COUNTERS; i++)
+	for_each_set_bit(i, &mask, 32)
 		kvm_pmu_stop_counter(vcpu, &pmu->pmc[i]);
 
 	bitmap_zero(vcpu->arch.pmu.chained, ARMV8_PMU_MAX_COUNTER_PAIRS);
@@ -527,10 +528,9 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val)
  */
 void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val)
 {
-	u64 mask;
+	unsigned long mask = kvm_pmu_valid_counter_mask(vcpu);
 	int i;
 
-	mask = kvm_pmu_valid_counter_mask(vcpu);
 	if (val & ARMV8_PMU_PMCR_E) {
 		kvm_pmu_enable_counter_mask(vcpu,
 		       __vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & mask);
@@ -542,7 +542,7 @@ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val)
 		kvm_pmu_set_counter_value(vcpu, ARMV8_PMU_CYCLE_IDX, 0);
 
 	if (val & ARMV8_PMU_PMCR_P) {
-		for (i = 0; i < ARMV8_PMU_CYCLE_IDX; i++)
+		for_each_set_bit(i, &mask, 32)
 			kvm_pmu_set_counter_value(vcpu, i, 0);
 	}
 }
-- 
2.20.1

