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.
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| @@ -995,6 +995,7 @@ struct kvm_ppc_resize_hpt { · 994 unmodified lines | ||
| 995 | 995 | #define KVM_CAP_ARM_SVE 170 |
| 996 | 996 | #define KVM_CAP_ARM_PTRAUTH_ADDRESS 171 |
| 997 | 997 | #define KVM_CAP_ARM_PTRAUTH_GENERIC 172 |
| 998 | +#define KVM_CAP_PMU_EVENT_FILTER 173 | |
| 998 | 999 | |
| 999 | 1000 | #ifdef KVM_CAP_IRQ_ROUTING |
| 1000 | 1001 | |
| @@ -1329,6 +1330,8 @@ struct kvm_s390_ucas_mapping { · 328 unmodified lines | ||
| 1329 | 1330 | #define KVM_PPC_GET_RMMU_INFO _IOW(KVMIO, 0xb0, struct kvm_ppc_rmmu_info) |
| 1330 | 1331 | /* Available with KVM_CAP_PPC_GET_CPU_CHAR */ |
| 1331 | 1332 | #define KVM_PPC_GET_CPU_CHAR _IOR(KVMIO, 0xb1, struct kvm_ppc_cpu_char) |
| 1333 | +/* Available with KVM_CAP_PMU_EVENT_FILTER */ | |
| 1334 | +#define KVM_SET_PMU_EVENT_FILTER _IOW(KVMIO, 0xb2, struct kvm_pmu_event_filter) | |
| 1332 | 1335 | |
| 1333 | 1336 | /* ioctl for vm fd */ |
| 1334 | 1337 | #define KVM_CREATE_DEVICE _IOWR(KVMIO, 0xe0, struct kvm_create_device) |