From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 69FAA2749CE for ; Wed, 17 Sep 2025 21:22:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.185 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758144126; cv=none; b=slSxVyzHgGM+LXNA0HPvjws9isNPvcza/bidlAW7RwvA1TPg0vOttR7qm7QTiP3XvBKVyjJt+mYju+AI/R7u6rQTU5qWRpaLlf8r4rKeyytZHVilh83OaLNlYVa95F6lrjqfA1ZUzITG80I+b8BlmeRIHCvIgLqIrtcIVIDt6QM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1758144126; c=relaxed/simple; bh=SzHRTvydUAOnrNTctQ/cxubaMWZQ2gSpHeYkGiI6J20=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZvBH/evweEU+ljT/VV//MlurGcWBhj2mj+9SjtVp1liV2qTVW7UyXqCDZHGmT16ktRLznbTGUXUMiOUk8qTtuffqiVPMHL67d07UNWF9ZtaPdf6tAvG9fphGGu5Hi3PyiDWtqx4R1+QM0iRX+hRwDwGaYAl94/5CaN6ZqpcngQw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=sWocmLbh; arc=none smtp.client-ip=91.218.175.185 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="sWocmLbh" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1758144122; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=mo4OqzfGjmLC2N8F8wqwEshYuK+X6JdNA0FmDWCtBF8=; b=sWocmLbhjmzHXxx9/n9OktxXOouX5Z9bF0An0NYSKi5RsOhXwodpmX8rtwH0+GchLsqJgr 1iRTAEwfKvXgHw38Oyx1Ku/2byxp/NYEwQbIqpp9kzZ0/mBXC/BMmk3qmxSKnm4Cq6K/yZ uiDQRKSV3p6avOqpTq/jv3ZWNReRaTA= From: Oliver Upton To: kvmarm@lists.linux.dev Cc: Marc Zyngier , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Paolo Bonzini , Sean Christopherson , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , David Hildenbrand , linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, Oliver Upton Subject: [PATCH 10/13] KVM: arm64: selftests: Use the vCPU attr for setting nr of PMU counters Date: Wed, 17 Sep 2025 14:20:40 -0700 Message-ID: <20250917212044.294760-11-oliver.upton@linux.dev> In-Reply-To: <20250917212044.294760-1-oliver.upton@linux.dev> References: <20250917212044.294760-1-oliver.upton@linux.dev> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Configuring the number of implemented counters via PMCR_EL0.N was a bad idea in retrospect as it interacts poorly with nested. Migrate the selftest to use the vCPU attribute instead of the KVM_SET_ONE_REG mechanism. Signed-off-by: Oliver Upton --- .../selftests/kvm/arm64/vpmu_counter_access.c | 59 +++++++++---------- 1 file changed, 28 insertions(+), 31 deletions(-) diff --git a/tools/testing/selftests/kvm/arm64/vpmu_counter_access.c b/tools/testing/selftests/kvm/arm64/vpmu_counter_access.c index 2a8f31c8e59f..ae36325c022f 100644 --- a/tools/testing/selftests/kvm/arm64/vpmu_counter_access.c +++ b/tools/testing/selftests/kvm/arm64/vpmu_counter_access.c @@ -44,11 +44,6 @@ static uint64_t get_pmcr_n(uint64_t pmcr) return FIELD_GET(ARMV8_PMU_PMCR_N, pmcr); } -static void set_pmcr_n(uint64_t *pmcr, uint64_t pmcr_n) -{ - u64p_replace_bits((__u64 *) pmcr, pmcr_n, ARMV8_PMU_PMCR_N); -} - static uint64_t get_counters_mask(uint64_t n) { uint64_t mask = BIT(ARMV8_PMU_CYCLE_IDX); @@ -414,10 +409,6 @@ static void create_vpmu_vm(void *guest_code) .attr = KVM_ARM_VCPU_PMU_V3_IRQ, .addr = (uint64_t)&irq, }; - struct kvm_device_attr init_attr = { - .group = KVM_ARM_VCPU_PMU_V3_CTRL, - .attr = KVM_ARM_VCPU_PMU_V3_INIT, - }; /* The test creates the vpmu_vm multiple times. Ensure a clean state */ memset(&vpmu_vm, 0, sizeof(vpmu_vm)); @@ -444,9 +435,7 @@ static void create_vpmu_vm(void *guest_code) pmuver >= ID_AA64DFR0_EL1_PMUVer_IMP, "Unexpected PMUVER (0x%x) on the vCPU with PMUv3", pmuver); - /* Initialize vPMU */ vcpu_ioctl(vpmu_vm.vcpu, KVM_SET_DEVICE_ATTR, &irq_attr); - vcpu_ioctl(vpmu_vm.vcpu, KVM_SET_DEVICE_ATTR, &init_attr); } static void destroy_vpmu_vm(void) @@ -472,33 +461,28 @@ static void run_vcpu(struct kvm_vcpu *vcpu, uint64_t pmcr_n) } } -static void test_create_vpmu_vm_with_pmcr_n(uint64_t pmcr_n, bool expect_fail) +static void test_create_vpmu_vm_with_nr_counters(unsigned int nr_counters, bool expect_fail) { struct kvm_vcpu *vcpu; - uint64_t pmcr, pmcr_orig; + unsigned int prev; + int ret; create_vpmu_vm(guest_code); vcpu = vpmu_vm.vcpu; - pmcr_orig = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0)); - pmcr = pmcr_orig; + prev = get_pmcr_n(vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0))); - /* - * Setting a larger value of PMCR.N should not modify the field, and - * return a success. - */ - set_pmcr_n(&pmcr, pmcr_n); - vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0), pmcr); - pmcr = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_PMCR_EL0)); + ret = __vcpu_device_attr_set(vcpu, KVM_ARM_VCPU_PMU_V3_CTRL, + KVM_ARM_VCPU_PMU_V3_SET_NR_COUNTERS, &nr_counters); if (expect_fail) - TEST_ASSERT(pmcr_orig == pmcr, - "PMCR.N modified by KVM to a larger value (PMCR: 0x%lx) for pmcr_n: 0x%lx", - pmcr, pmcr_n); + TEST_ASSERT(ret && errno == EINVAL, + "Setting more PMU counters (%u) than available (%u) unexpectedly succeeded", + nr_counters, prev); else - TEST_ASSERT(pmcr_n == get_pmcr_n(pmcr), - "Failed to update PMCR.N to %lu (received: %lu)", - pmcr_n, get_pmcr_n(pmcr)); + TEST_ASSERT(!ret, KVM_IOCTL_ERROR(KVM_SET_DEVICE_ATTR, ret)); + + vcpu_device_attr_set(vcpu, KVM_ARM_VCPU_PMU_V3_CTRL, KVM_ARM_VCPU_PMU_V3_INIT, NULL); } /* @@ -513,7 +497,7 @@ static void run_access_test(uint64_t pmcr_n) pr_debug("Test with pmcr_n %lu\n", pmcr_n); - test_create_vpmu_vm_with_pmcr_n(pmcr_n, false); + test_create_vpmu_vm_with_nr_counters(pmcr_n, false); vcpu = vpmu_vm.vcpu; /* Save the initial sp to restore them later to run the guest again */ @@ -554,7 +538,7 @@ static void run_pmregs_validity_test(uint64_t pmcr_n) uint64_t set_reg_id, clr_reg_id, reg_val; uint64_t valid_counters_mask, max_counters_mask; - test_create_vpmu_vm_with_pmcr_n(pmcr_n, false); + test_create_vpmu_vm_with_nr_counters(pmcr_n, false); vcpu = vpmu_vm.vcpu; valid_counters_mask = get_counters_mask(pmcr_n); @@ -608,7 +592,7 @@ static void run_error_test(uint64_t pmcr_n) { pr_debug("Error test with pmcr_n %lu (larger than the host)\n", pmcr_n); - test_create_vpmu_vm_with_pmcr_n(pmcr_n, true); + test_create_vpmu_vm_with_nr_counters(pmcr_n, true); destroy_vpmu_vm(); } @@ -626,12 +610,25 @@ static uint64_t get_pmcr_n_limit(void) return get_pmcr_n(pmcr); } +static bool kvm_supports_nr_counters_attr(void) +{ + bool supported; + + create_vpmu_vm(NULL); + supported = !__vcpu_has_device_attr(vpmu_vm.vcpu, KVM_ARM_VCPU_PMU_V3_CTRL, + KVM_ARM_VCPU_PMU_V3_SET_NR_COUNTERS); + destroy_vpmu_vm(); + + return supported; +} + int main(void) { uint64_t i, pmcr_n; TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_PMU_V3)); TEST_REQUIRE(kvm_supports_vgic_v3()); + TEST_REQUIRE(kvm_supports_nr_counters_attr()); pmcr_n = get_pmcr_n_limit(); for (i = 0; i <= pmcr_n; i++) { -- 2.47.3