* [PATCH v4 0/3] KVM: x86: Provide per VM capability for disabling PMU virtualization
@ 2022-01-21 22:29 David Dunn
2022-01-21 22:29 ` [PATCH v4 1/3] " David Dunn
` (2 more replies)
0 siblings, 3 replies; 5+ messages in thread
From: David Dunn @ 2022-01-21 22:29 UTC (permalink / raw)
To: kvm, pbonzini, like.xu.linux, jmattson, cloudliang, seanjc; +Cc: daviddunn
This patch set allows usermode to disable PMU virtualization on
individual x86 VMs. When disabled, the PMU is not advertised to
or accessible from the guest.
Corrected changes that I missed committing into v3 patch set. This
incorporates Like's suggestions from reviewing v2.
David Dunn (3):
KVM: x86: Provide per VM capability for disabling PMU virtualization
KVM: selftests: Allow creation of selftest VM without vcpus
KVM: selftests: Verify disabling PMU virtualization via
KVM_CAP_CONFIG_PMU
Documentation/virt/kvm/api.rst | 21 ++++++++
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/cpuid.c | 8 ++++
arch/x86/kvm/svm/pmu.c | 2 +-
arch/x86/kvm/vmx/pmu_intel.c | 2 +-
arch/x86/kvm/x86.c | 12 +++++
include/uapi/linux/kvm.h | 4 ++
tools/include/uapi/linux/kvm.h | 4 ++
.../selftests/kvm/include/kvm_util_base.h | 3 ++
tools/testing/selftests/kvm/lib/kvm_util.c | 48 ++++++++++++++-----
.../kvm/x86_64/pmu_event_filter_test.c | 45 +++++++++++++++++
11 files changed, 135 insertions(+), 15 deletions(-)
--
2.35.0.rc0.227.g00780c9af4-goog
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v4 1/3] KVM: x86: Provide per VM capability for disabling PMU virtualization
2022-01-21 22:29 [PATCH v4 0/3] KVM: x86: Provide per VM capability for disabling PMU virtualization David Dunn
@ 2022-01-21 22:29 ` David Dunn
2022-01-23 4:56 ` Like Xu
2022-01-21 22:29 ` [PATCH v4 2/3] KVM: selftests: Allow creation of selftest VM without vcpus David Dunn
2022-01-21 22:29 ` [PATCH v4 3/3] KVM: selftests: Verify disabling PMU virtualization via KVM_CAP_CONFIG_PMU David Dunn
2 siblings, 1 reply; 5+ messages in thread
From: David Dunn @ 2022-01-21 22:29 UTC (permalink / raw)
To: kvm, pbonzini, like.xu.linux, jmattson, cloudliang, seanjc; +Cc: daviddunn
KVM_CAP_PMU_DISABLE is used to disable PMU virtualization on individual
x86 VMs. PMU configuration must be done prior to creating VCPUs.
To enable future extension, KVM_CAP_PMU_CAPABILITY reports available
settings via bitmask when queried via check_extension.
For VMs that have PMU virtualization disabled, CPUID leaf 0xA will be
cleared to notify guests.
Signed-off-by: David Dunn <daviddunn@google.com>
---
Documentation/virt/kvm/api.rst | 21 +++++++++++++++++++++
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/cpuid.c | 8 ++++++++
arch/x86/kvm/svm/pmu.c | 2 +-
arch/x86/kvm/vmx/pmu_intel.c | 2 +-
arch/x86/kvm/x86.c | 12 ++++++++++++
include/uapi/linux/kvm.h | 4 ++++
tools/include/uapi/linux/kvm.h | 4 ++++
8 files changed, 52 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index bb8cfddbb22d..375d35e8ac47 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -7559,3 +7559,24 @@ The argument to KVM_ENABLE_CAP is also a bitmask, and must be a subset
of the result of KVM_CHECK_EXTENSION. KVM will forward to userspace
the hypercalls whose corresponding bit is in the argument, and return
ENOSYS for the others.
+
+8.35 KVM_CAP_PMU_CAPABILITY
+---------------------------
+
+:Capability KVM_CAP_PMU_CAPABILITY
+:Architectures: x86
+:Type: vm
+
+This capability alters PMU virtualization in KVM.
+
+Calling KVM_CHECK_EXTENSION for this capability returns a bitmask of
+PMU virtualization capabilities that can be adjusted on a VM.
+
+The argument to KVM_ENABLE_CAP is also a bitmask and selects specific
+PMU virtualization capabilities to be applied to the VM. This can
+only be invoked on a VM prior to the creation of VCPUs.
+
+At this time, KVM_CAP_PMU_DISABLE is the only capability. Setting
+this capability will disable PMU virtualization for that VM. When
+PMU virtualization is disabled, CPUID leaf 0xA will always be cleared
+to properly inform Intel guests.
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 682ad02a4e58..5cdcd4a7671b 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1232,6 +1232,7 @@ struct kvm_arch {
hpa_t hv_root_tdp;
spinlock_t hv_root_tdp_lock;
#endif
+ bool enable_pmu;
};
struct kvm_vm_stat {
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 3902c28fb6cb..a91c4a00c913 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -217,6 +217,14 @@ static void __kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu, struct kvm_cpuid_e
cpuid_entry_change(best, X86_FEATURE_OSPKE,
kvm_read_cr4_bits(vcpu, X86_CR4_PKE));
+ best = cpuid_entry2_find(entries, nent, 0xA, 0);
+ if (best && !vcpu->kvm->arch.enable_pmu) {
+ best->eax = 0;
+ best->ebx = 0;
+ best->ecx = 0;
+ best->edx = 0;
+ }
+
best = cpuid_entry2_find(entries, nent, 0xD, 0);
if (best)
best->ebx = xstate_required_size(vcpu->arch.xcr0, false);
diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c
index 5aa45f13b16d..d4de52409335 100644
--- a/arch/x86/kvm/svm/pmu.c
+++ b/arch/x86/kvm/svm/pmu.c
@@ -101,7 +101,7 @@ static inline struct kvm_pmc *get_gp_pmc_amd(struct kvm_pmu *pmu, u32 msr,
{
struct kvm_vcpu *vcpu = pmu_to_vcpu(pmu);
- if (!enable_pmu)
+ if (!vcpu->kvm->arch.enable_pmu)
return NULL;
switch (msr) {
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 466d18fc0c5d..2c5868d77268 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -487,7 +487,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
pmu->reserved_bits = 0xffffffff00200000ull;
entry = kvm_find_cpuid_entry(vcpu, 0xa, 0);
- if (!entry || !enable_pmu)
+ if (!entry || !vcpu->kvm->arch.enable_pmu)
return;
eax.full = entry->eax;
edx.full = entry->edx;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 55518b7d3b96..a033f019a3f0 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4326,6 +4326,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
if (r < sizeof(struct kvm_xsave))
r = sizeof(struct kvm_xsave);
break;
+ case KVM_CAP_PMU_CAPABILITY:
+ r = enable_pmu ? KVM_CAP_PMU_MASK : 0;
+ break;
}
default:
break;
@@ -5937,6 +5940,14 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
kvm->arch.exit_on_emulation_error = cap->args[0];
r = 0;
break;
+ case KVM_CAP_PMU_CAPABILITY:
+ r = -EINVAL;
+ if (!enable_pmu || kvm->created_vcpus > 0 ||
+ cap->args[0] & ~KVM_CAP_PMU_MASK)
+ break;
+ kvm->arch.enable_pmu = !(cap->args[0] & KVM_CAP_PMU_DISABLE);
+ r = 0;
+ break;
default:
r = -EINVAL;
break;
@@ -11562,6 +11573,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
kvm->arch.guest_can_read_msr_platform_info = true;
+ kvm->arch.enable_pmu = enable_pmu;
#if IS_ENABLED(CONFIG_HYPERV)
spin_lock_init(&kvm->arch.hv_root_tdp_lock);
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 9563d294f181..1c5e6e172817 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1133,6 +1133,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM 206
#define KVM_CAP_VM_GPA_BITS 207
#define KVM_CAP_XSAVE2 208
+#define KVM_CAP_PMU_CAPABILITY 209
#ifdef KVM_CAP_IRQ_ROUTING
@@ -1972,6 +1973,9 @@ struct kvm_dirty_gfn {
#define KVM_BUS_LOCK_DETECTION_OFF (1 << 0)
#define KVM_BUS_LOCK_DETECTION_EXIT (1 << 1)
+#define KVM_CAP_PMU_DISABLE (1 << 0)
+#define KVM_CAP_PMU_MASK (KVM_CAP_PMU_DISABLE)
+
/**
* struct kvm_stats_header - Header of per vm/vcpu binary statistics data.
* @flags: Some extra information for header, always 0 for now.
diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
index 9563d294f181..a361cf6e8604 100644
--- a/tools/include/uapi/linux/kvm.h
+++ b/tools/include/uapi/linux/kvm.h
@@ -1133,6 +1133,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM 206
#define KVM_CAP_VM_GPA_BITS 207
#define KVM_CAP_XSAVE2 208
+#define KVM_CAP_PMU_CAPABILITY 209
#ifdef KVM_CAP_IRQ_ROUTING
@@ -1972,6 +1973,9 @@ struct kvm_dirty_gfn {
#define KVM_BUS_LOCK_DETECTION_OFF (1 << 0)
#define KVM_BUS_LOCK_DETECTION_EXIT (1 << 1)
+#define KVM_CAP_PMU_DISABLE (1 << 0)
+#define KVM_CAP_PMU_MASK (KVM_PMU_CONFIG_DISABLE)
+
/**
* struct kvm_stats_header - Header of per vm/vcpu binary statistics data.
* @flags: Some extra information for header, always 0 for now.
--
2.35.0.rc0.227.g00780c9af4-goog
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v4 2/3] KVM: selftests: Allow creation of selftest VM without vcpus
2022-01-21 22:29 [PATCH v4 0/3] KVM: x86: Provide per VM capability for disabling PMU virtualization David Dunn
2022-01-21 22:29 ` [PATCH v4 1/3] " David Dunn
@ 2022-01-21 22:29 ` David Dunn
2022-01-21 22:29 ` [PATCH v4 3/3] KVM: selftests: Verify disabling PMU virtualization via KVM_CAP_CONFIG_PMU David Dunn
2 siblings, 0 replies; 5+ messages in thread
From: David Dunn @ 2022-01-21 22:29 UTC (permalink / raw)
To: kvm, pbonzini, like.xu.linux, jmattson, cloudliang, seanjc; +Cc: daviddunn
Break out portion of vm_create_with_vcpus so that selftests can modify
the VM prior to creating vcpus.
Signed-off-by: David Dunn <daviddunn@google.com>
---
.../selftests/kvm/include/kvm_util_base.h | 3 ++
tools/testing/selftests/kvm/lib/kvm_util.c | 48 ++++++++++++++-----
2 files changed, 38 insertions(+), 13 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index 66775de26952..0454027d588d 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -336,6 +336,9 @@ struct kvm_vm *vm_create_with_vcpus(enum vm_guest_mode mode, uint32_t nr_vcpus,
uint32_t num_percpu_pages, void *guest_code,
uint32_t vcpuids[]);
+/* First phase of vm_create_with_vcpus, allows customization before vcpu add */
+struct kvm_vm *vm_create_without_vcpus(enum vm_guest_mode mode, uint64_t pages);
+
/*
* Adds a vCPU with reasonable defaults (e.g. a stack)
*
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 8c53f96ab7fe..f44fd2210c66 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -362,6 +362,40 @@ struct kvm_vm *vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm)
return vm;
}
+/*
+ * VM Create without creating VCPUs
+ *
+ * Input Args:
+ * mode - VM Mode (e.g. VM_MODE_P52V48_4K)
+ * pages - pages of memory required for VM
+ *
+ * Output Args: None
+ *
+ * Return:
+ * Pointer to opaque structure that describes the created VM.
+ *
+ * Creates a VM with the mode specified by mode (e.g. VM_MODE_P52V48_4K).
+ */
+struct kvm_vm *vm_create_without_vcpus(enum vm_guest_mode mode, uint64_t pages)
+{
+ struct kvm_vm *vm;
+
+#ifdef __x86_64__
+ /*
+ * Permission needs to be requested before KVM_SET_CPUID2.
+ */
+ vm_xsave_req_perm();
+#endif
+ vm = vm_create(mode, pages, O_RDWR);
+
+ kvm_vm_elf_load(vm, program_invocation_name);
+
+#ifdef __x86_64__
+ vm_create_irqchip(vm);
+#endif
+ return vm;
+}
+
/*
* VM Create with customized parameters
*
@@ -393,13 +427,6 @@ struct kvm_vm *vm_create_with_vcpus(enum vm_guest_mode mode, uint32_t nr_vcpus,
struct kvm_vm *vm;
int i;
-#ifdef __x86_64__
- /*
- * Permission needs to be requested before KVM_SET_CPUID2.
- */
- vm_xsave_req_perm();
-#endif
-
/* Force slot0 memory size not small than DEFAULT_GUEST_PHY_PAGES */
if (slot0_mem_pages < DEFAULT_GUEST_PHY_PAGES)
slot0_mem_pages = DEFAULT_GUEST_PHY_PAGES;
@@ -419,13 +446,8 @@ struct kvm_vm *vm_create_with_vcpus(enum vm_guest_mode mode, uint32_t nr_vcpus,
nr_vcpus, kvm_check_cap(KVM_CAP_MAX_VCPUS));
pages = vm_adjust_num_guest_pages(mode, pages);
- vm = vm_create(mode, pages, O_RDWR);
- kvm_vm_elf_load(vm, program_invocation_name);
-
-#ifdef __x86_64__
- vm_create_irqchip(vm);
-#endif
+ vm = vm_create_without_vcpus(mode, pages);
for (i = 0; i < nr_vcpus; ++i) {
uint32_t vcpuid = vcpuids ? vcpuids[i] : i;
--
2.35.0.rc0.227.g00780c9af4-goog
^ permalink raw reply related [flat|nested] 5+ messages in thread
* [PATCH v4 3/3] KVM: selftests: Verify disabling PMU virtualization via KVM_CAP_CONFIG_PMU
2022-01-21 22:29 [PATCH v4 0/3] KVM: x86: Provide per VM capability for disabling PMU virtualization David Dunn
2022-01-21 22:29 ` [PATCH v4 1/3] " David Dunn
2022-01-21 22:29 ` [PATCH v4 2/3] KVM: selftests: Allow creation of selftest VM without vcpus David Dunn
@ 2022-01-21 22:29 ` David Dunn
2 siblings, 0 replies; 5+ messages in thread
From: David Dunn @ 2022-01-21 22:29 UTC (permalink / raw)
To: kvm, pbonzini, like.xu.linux, jmattson, cloudliang, seanjc; +Cc: daviddunn
On a VM with PMU disabled via KVM_CAP_PMU_CONFIG, the PMU will not be
usable by the guest. On Intel, this causes a #GP. And on AMD, the
counters no longer increment.
KVM_CAP_PMU_CONFIG must be invoked on a VM prior to creating VCPUs.
Signed-off-by: David Dunn <daviddunn@google.com>
---
.../kvm/x86_64/pmu_event_filter_test.c | 45 +++++++++++++++++++
1 file changed, 45 insertions(+)
diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
index c715adcbd487..cffa2e019eac 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
@@ -325,6 +325,49 @@ static void test_not_member_allow_list(struct kvm_vm *vm)
TEST_ASSERT(!count, "Disallowed PMU Event is counting");
}
+/*
+ * Verify KVM_CAP_PMU_DISABLE prevents the use of the PMU.
+ *
+ * Note that KVM_CAP_PMU_CAPABILITY must be invoked prior to creating VCPUs.
+ */
+static void test_pmu_config_disable(void (*guest_code)(void))
+{
+ int r;
+ struct kvm_vm *vm;
+ struct kvm_cpuid2 *cpuid2;
+ struct kvm_cpuid_entry2 *entry;
+ struct kvm_enable_cap cap = { 0 };
+ bool sane;
+
+ r = kvm_check_cap(KVM_CAP_PMU_CAPABILITY);
+ if ((r & KVM_CAP_PMU_DISABLE) == 0)
+ return;
+
+ vm = vm_create_without_vcpus(VM_MODE_DEFAULT, DEFAULT_GUEST_PHY_PAGES);
+
+ cap.cap = KVM_CAP_PMU_CAPABILITY;
+ cap.args[0] = KVM_CAP_PMU_DISABLE;
+ r = vm_enable_cap(vm, &cap);
+ TEST_ASSERT(r == 0, "Failed KVM_CAP_PMU_DISABLE.");
+
+ vm_vcpu_add_default(vm, VCPU_ID, guest_code);
+ vm_init_descriptor_tables(vm);
+ vcpu_init_descriptor_tables(vm, VCPU_ID);
+
+ cpuid2 = vcpu_get_cpuid(vm, VCPU_ID);
+ entry = get_cpuid(cpuid2, 0xA, 0);
+ if (entry) {
+ TEST_ASSERT(entry->eax == 0 && entry->ebx == 0 &&
+ entry->ecx == 0 && entry->edx == 0,
+ "CPUID should not advertise PMU when disabled.");
+ }
+
+ sane = sanity_check_pmu(vm);
+ TEST_ASSERT(!sane, "Guest should not be able to use disabled PMU.");
+
+ kvm_vm_free(vm);
+}
+
/*
* Check for a non-zero PMU version, at least one general-purpose
* counter per logical processor, an EBX bit vector of length greater
@@ -430,5 +473,7 @@ int main(int argc, char *argv[])
kvm_vm_free(vm);
+ test_pmu_config_disable(guest_code);
+
return 0;
}
--
2.35.0.rc0.227.g00780c9af4-goog
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v4 1/3] KVM: x86: Provide per VM capability for disabling PMU virtualization
2022-01-21 22:29 ` [PATCH v4 1/3] " David Dunn
@ 2022-01-23 4:56 ` Like Xu
0 siblings, 0 replies; 5+ messages in thread
From: Like Xu @ 2022-01-23 4:56 UTC (permalink / raw)
To: David Dunn; +Cc: kvm, pbonzini, jmattson, cloudliang, seanjc
On 22/1/2022 6:29 am, David Dunn wrote:
> KVM_CAP_PMU_DISABLE is used to disable PMU virtualization on individual
> x86 VMs. PMU configuration must be done prior to creating VCPUs.
>
> To enable future extension, KVM_CAP_PMU_CAPABILITY reports available
> settings via bitmask when queried via check_extension.
>
> For VMs that have PMU virtualization disabled, CPUID leaf 0xA will be
> cleared to notify guests.
>
> Signed-off-by: David Dunn <daviddunn@google.com>
> ---
> Documentation/virt/kvm/api.rst | 21 +++++++++++++++++++++
> arch/x86/include/asm/kvm_host.h | 1 +
> arch/x86/kvm/cpuid.c | 8 ++++++++
> arch/x86/kvm/svm/pmu.c | 2 +-
> arch/x86/kvm/vmx/pmu_intel.c | 2 +-
> arch/x86/kvm/x86.c | 12 ++++++++++++
> include/uapi/linux/kvm.h | 4 ++++
> tools/include/uapi/linux/kvm.h | 4 ++++
> 8 files changed, 52 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
> index bb8cfddbb22d..375d35e8ac47 100644
> --- a/Documentation/virt/kvm/api.rst
> +++ b/Documentation/virt/kvm/api.rst
> @@ -7559,3 +7559,24 @@ The argument to KVM_ENABLE_CAP is also a bitmask, and must be a subset
> of the result of KVM_CHECK_EXTENSION. KVM will forward to userspace
> the hypercalls whose corresponding bit is in the argument, and return
> ENOSYS for the others.
> +
> +8.35 KVM_CAP_PMU_CAPABILITY
> +---------------------------
> +
> +:Capability KVM_CAP_PMU_CAPABILITY
> +:Architectures: x86
> +:Type: vm
:Parameters: args[0] defines ....
:Returns: 0 on success, -EINVAL when args[0] contains invalid bits
> +
> +This capability alters PMU virtualization in KVM.
> +
> +Calling KVM_CHECK_EXTENSION for this capability returns a bitmask of
> +PMU virtualization capabilities that can be adjusted on a VM.
> +
> +The argument to KVM_ENABLE_CAP is also a bitmask and selects specific
> +PMU virtualization capabilities to be applied to the VM. This can
> +only be invoked on a VM prior to the creation of VCPUs.
> +
> +At this time, KVM_CAP_PMU_DISABLE is the only capability. Setting
> +this capability will disable PMU virtualization for that VM. When
> +PMU virtualization is disabled, CPUID leaf 0xA will always be cleared
> +to properly inform Intel guests.
Valid bits in args[0] are::
#define KVM_CAP_PMU_DISABLE (1 << 0)
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index 682ad02a4e58..5cdcd4a7671b 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -1232,6 +1232,7 @@ struct kvm_arch {
> hpa_t hv_root_tdp;
> spinlock_t hv_root_tdp_lock;
> #endif
> + bool enable_pmu;
> };
>
> struct kvm_vm_stat {
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index 3902c28fb6cb..a91c4a00c913 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -217,6 +217,14 @@ static void __kvm_update_cpuid_runtime(struct kvm_vcpu *vcpu, struct kvm_cpuid_e
> cpuid_entry_change(best, X86_FEATURE_OSPKE,
> kvm_read_cr4_bits(vcpu, X86_CR4_PKE));
>
> + best = cpuid_entry2_find(entries, nent, 0xA, 0);
> + if (best && !vcpu->kvm->arch.enable_pmu) {
> + best->eax = 0;
> + best->ebx = 0;
> + best->ecx = 0;
> + best->edx = 0;
> + }
Sorry, I don't think we should do this stuff for the buggy user space.
For others, Reviewed-by: Like Xu <likexu@tencent.com>
> +
> best = cpuid_entry2_find(entries, nent, 0xD, 0);
> if (best)
> best->ebx = xstate_required_size(vcpu->arch.xcr0, false);
> diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c
> index 5aa45f13b16d..d4de52409335 100644
> --- a/arch/x86/kvm/svm/pmu.c
> +++ b/arch/x86/kvm/svm/pmu.c
> @@ -101,7 +101,7 @@ static inline struct kvm_pmc *get_gp_pmc_amd(struct kvm_pmu *pmu, u32 msr,
> {
> struct kvm_vcpu *vcpu = pmu_to_vcpu(pmu);
>
> - if (!enable_pmu)
> + if (!vcpu->kvm->arch.enable_pmu)
> return NULL;
>
> switch (msr) {
> diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
> index 466d18fc0c5d..2c5868d77268 100644
> --- a/arch/x86/kvm/vmx/pmu_intel.c
> +++ b/arch/x86/kvm/vmx/pmu_intel.c
> @@ -487,7 +487,7 @@ static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
> pmu->reserved_bits = 0xffffffff00200000ull;
>
> entry = kvm_find_cpuid_entry(vcpu, 0xa, 0);
> - if (!entry || !enable_pmu)
> + if (!entry || !vcpu->kvm->arch.enable_pmu)
> return;
> eax.full = entry->eax;
> edx.full = entry->edx;
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 55518b7d3b96..a033f019a3f0 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -4326,6 +4326,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
> if (r < sizeof(struct kvm_xsave))
> r = sizeof(struct kvm_xsave);
> break;
> + case KVM_CAP_PMU_CAPABILITY:
> + r = enable_pmu ? KVM_CAP_PMU_MASK : 0;
> + break;
> }
> default:
> break;
> @@ -5937,6 +5940,14 @@ int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
> kvm->arch.exit_on_emulation_error = cap->args[0];
> r = 0;
> break;
> + case KVM_CAP_PMU_CAPABILITY:
> + r = -EINVAL;
> + if (!enable_pmu || kvm->created_vcpus > 0 ||
> + cap->args[0] & ~KVM_CAP_PMU_MASK)
> + break;
> + kvm->arch.enable_pmu = !(cap->args[0] & KVM_CAP_PMU_DISABLE);
> + r = 0;
> + break;
> default:
> r = -EINVAL;
> break;
> @@ -11562,6 +11573,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
> raw_spin_unlock_irqrestore(&kvm->arch.tsc_write_lock, flags);
>
> kvm->arch.guest_can_read_msr_platform_info = true;
> + kvm->arch.enable_pmu = enable_pmu;
>
> #if IS_ENABLED(CONFIG_HYPERV)
> spin_lock_init(&kvm->arch.hv_root_tdp_lock);
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 9563d294f181..1c5e6e172817 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1133,6 +1133,7 @@ struct kvm_ppc_resize_hpt {
> #define KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM 206
> #define KVM_CAP_VM_GPA_BITS 207
> #define KVM_CAP_XSAVE2 208
> +#define KVM_CAP_PMU_CAPABILITY 209
>
> #ifdef KVM_CAP_IRQ_ROUTING
>
> @@ -1972,6 +1973,9 @@ struct kvm_dirty_gfn {
> #define KVM_BUS_LOCK_DETECTION_OFF (1 << 0)
> #define KVM_BUS_LOCK_DETECTION_EXIT (1 << 1)
>
> +#define KVM_CAP_PMU_DISABLE (1 << 0)
> +#define KVM_CAP_PMU_MASK (KVM_CAP_PMU_DISABLE)
> +
> /**
> * struct kvm_stats_header - Header of per vm/vcpu binary statistics data.
> * @flags: Some extra information for header, always 0 for now.
> diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
> index 9563d294f181..a361cf6e8604 100644
> --- a/tools/include/uapi/linux/kvm.h
> +++ b/tools/include/uapi/linux/kvm.h
> @@ -1133,6 +1133,7 @@ struct kvm_ppc_resize_hpt {
> #define KVM_CAP_VM_MOVE_ENC_CONTEXT_FROM 206
> #define KVM_CAP_VM_GPA_BITS 207
> #define KVM_CAP_XSAVE2 208
> +#define KVM_CAP_PMU_CAPABILITY 209
>
> #ifdef KVM_CAP_IRQ_ROUTING
>
> @@ -1972,6 +1973,9 @@ struct kvm_dirty_gfn {
> #define KVM_BUS_LOCK_DETECTION_OFF (1 << 0)
> #define KVM_BUS_LOCK_DETECTION_EXIT (1 << 1)
>
> +#define KVM_CAP_PMU_DISABLE (1 << 0)
> +#define KVM_CAP_PMU_MASK (KVM_PMU_CONFIG_DISABLE)
> +
> /**
> * struct kvm_stats_header - Header of per vm/vcpu binary statistics data.
> * @flags: Some extra information for header, always 0 for now.
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-01-23 4:56 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-01-21 22:29 [PATCH v4 0/3] KVM: x86: Provide per VM capability for disabling PMU virtualization David Dunn
2022-01-21 22:29 ` [PATCH v4 1/3] " David Dunn
2022-01-23 4:56 ` Like Xu
2022-01-21 22:29 ` [PATCH v4 2/3] KVM: selftests: Allow creation of selftest VM without vcpus David Dunn
2022-01-21 22:29 ` [PATCH v4 3/3] KVM: selftests: Verify disabling PMU virtualization via KVM_CAP_CONFIG_PMU David Dunn
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.