KVM: x86: PMU Event Filter

Some events can provide a guest with information about other guests or the
host (e.g. L3 cache stats); providing the capability to restrict access
to a "safe" set of events would limit the potential for the PMU to be used
in any side channel attacks. This change introduces a new VM ioctl that
sets an event filter. If the guest attempts to program a counter for
any blacklisted or non-whitelisted event, the kernel counter won't be
created, so any RDPMC/RDMSR will show 0 instances of that event.

Signed-off-by: Eric Hankland <ehankland@google.com>
[Lots of changes. All remaining bugs are probably mine. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Eric Hankland
2019-07-10 18:25:15 -07:00
committed by Paolo Bonzini
parent cdc238eb72
commit 66bb8a065f
7 changed files with 110 additions and 0 deletions

View File

@@ -995,6 +995,7 @@ struct kvm_ppc_resize_hpt {
#define KVM_CAP_ARM_SVE 170
#define KVM_CAP_ARM_PTRAUTH_ADDRESS 171
#define KVM_CAP_ARM_PTRAUTH_GENERIC 172
#define KVM_CAP_PMU_EVENT_FILTER 173
#ifdef KVM_CAP_IRQ_ROUTING
@@ -1329,6 +1330,8 @@ struct kvm_s390_ucas_mapping {
#define KVM_PPC_GET_RMMU_INFO _IOW(KVMIO, 0xb0, struct kvm_ppc_rmmu_info)
/* Available with KVM_CAP_PPC_GET_CPU_CHAR */
#define KVM_PPC_GET_CPU_CHAR _IOR(KVMIO, 0xb1, struct kvm_ppc_cpu_char)
/* Available with KVM_CAP_PMU_EVENT_FILTER */
#define KVM_SET_PMU_EVENT_FILTER _IOW(KVMIO, 0xb2, struct kvm_pmu_event_filter)
/* ioctl for vm fd */
#define KVM_CREATE_DEVICE _IOWR(KVMIO, 0xe0, struct kvm_create_device)