xref: /kvmtool/x86/cpuid.c (revision 5c3d55fa6f0e4a7591f7edc4dea1ad695d6e1935)
1*5c3d55faSPekka Enberg #include "kvm/kvm-cpu.h"
2*5c3d55faSPekka Enberg 
3a1fe6bc5SPekka Enberg #include "kvm/kvm.h"
4a1fe6bc5SPekka Enberg #include "kvm/util.h"
5a1fe6bc5SPekka Enberg 
6a1fe6bc5SPekka Enberg #include <sys/ioctl.h>
7a1fe6bc5SPekka Enberg #include <stdlib.h>
8a1fe6bc5SPekka Enberg #include <assert.h>
9a1fe6bc5SPekka Enberg 
101e1b3818SPekka Enberg #define CPUID_FUNC_PERFMON		0x0A
111e1b3818SPekka Enberg 
12a1fe6bc5SPekka Enberg #define	MAX_KVM_CPUID_ENTRIES		100
13a1fe6bc5SPekka Enberg 
141e1b3818SPekka Enberg static void filter_cpuid(struct kvm_cpuid2 *kvm_cpuid)
151e1b3818SPekka Enberg {
161e1b3818SPekka Enberg 	unsigned int i;
171e1b3818SPekka Enberg 
181e1b3818SPekka Enberg 	/*
191e1b3818SPekka Enberg 	 * Filter CPUID functions that are not supported by the hypervisor.
201e1b3818SPekka Enberg 	 */
211e1b3818SPekka Enberg 	for (i = 0; i < kvm_cpuid->nent; i++) {
221e1b3818SPekka Enberg 		struct kvm_cpuid_entry2 *entry = &kvm_cpuid->entries[i];
231e1b3818SPekka Enberg 
241e1b3818SPekka Enberg 		switch (entry->function) {
251e1b3818SPekka Enberg 		case CPUID_FUNC_PERFMON:
261e1b3818SPekka Enberg 			entry->eax	= 0x00;	/* disable it */
271e1b3818SPekka Enberg 			break;
281e1b3818SPekka Enberg 		default:
291e1b3818SPekka Enberg 			/* Keep the CPUID function as -is */
301e1b3818SPekka Enberg 			break;
311e1b3818SPekka Enberg 		};
321e1b3818SPekka Enberg 	}
331e1b3818SPekka Enberg }
341e1b3818SPekka Enberg 
35*5c3d55faSPekka Enberg void kvm_cpu__setup_cpuid(struct kvm_cpu *self)
36a1fe6bc5SPekka Enberg {
37a1fe6bc5SPekka Enberg 	struct kvm_cpuid2 *kvm_cpuid;
38a1fe6bc5SPekka Enberg 
39bb988cf5SAsias He 	kvm_cpuid = calloc(1, sizeof(*kvm_cpuid) + MAX_KVM_CPUID_ENTRIES * sizeof(*kvm_cpuid->entries));
40a1fe6bc5SPekka Enberg 
41bb988cf5SAsias He 	kvm_cpuid->nent = MAX_KVM_CPUID_ENTRIES;
42*5c3d55faSPekka Enberg 	if (ioctl(self->kvm->sys_fd, KVM_GET_SUPPORTED_CPUID, kvm_cpuid) < 0)
43bb988cf5SAsias He 		die_perror("KVM_GET_SUPPORTED_CPUID failed");
44a1fe6bc5SPekka Enberg 
451e1b3818SPekka Enberg 	filter_cpuid(kvm_cpuid);
461e1b3818SPekka Enberg 
47a1fe6bc5SPekka Enberg 	if (ioctl(self->vcpu_fd, KVM_SET_CPUID2, kvm_cpuid) < 0)
48a1fe6bc5SPekka Enberg 		die_perror("KVM_SET_CPUID2 failed");
49a1fe6bc5SPekka Enberg 
50bb988cf5SAsias He 	free(kvm_cpuid);
51a1fe6bc5SPekka Enberg }
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