| Message ID | 1241359444-8538-2-git-send-email-avi@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Avi Kivity wrote: > kvm does not support all cpu features; add support for dunamically querying > the supported feature set. > > Signed-off-by: Avi Kivity <avi@redhat.com> > --- > kvm.h | 3 ++ > target-i386/kvm.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 83 insertions(+), 0 deletions(-) > > diff --git a/kvm.h b/kvm.h > index bd4e8d4..c134c45 100644 > --- a/kvm.h > +++ b/kvm.h > @@ -124,6 +124,9 @@ void kvm_arch_remove_all_hw_breakpoints(void); > > void kvm_arch_update_guest_debug(CPUState *env, struct kvm_guest_debug *dbg); > > +uint32_t kvm_arch_get_supported_cpuid(CPUState *env, uint32_t function, > + int reg); > + > /* generic hooks - to be moved/refactored once there are more users */ > > static inline void cpu_synchronize_state(CPUState *env, int modified) > diff --git a/target-i386/kvm.c b/target-i386/kvm.c > index b534b2d..5f54ff5 100644 > --- a/target-i386/kvm.c > +++ b/target-i386/kvm.c > @@ -34,6 +34,86 @@ > do { } while (0) > #endif > > +#ifdef KVM_CAP_EXT_CPUID > + > +static struct kvm_cpuid2 *try_get_cpuid(KVMState *s, int max) > +{ > + struct kvm_cpuid2 *cpuid; > + int r, size; > + > + size = sizeof(*cpuid) + max * sizeof(*cpuid->entries); > + cpuid = (struct kvm_cpuid2 *)qemu_mallocz(size); > + cpuid->nent = max; > + r = kvm_ioctl(s, KVM_GET_SUPPORTED_CPUID, cpuid); > + if (r < 0) { > + if (r == -E2BIG) { > + qemu_free(cpuid); > + return NULL; > + } else { > + fprintf(stderr, "KVM_GET_SUPPORTED_CPUID failed: %s\n", > + strerror(-r)); > + exit(1); > + } > + } > + return cpuid; > +} > + > +uint32_t kvm_arch_get_supported_cpuid(CPUState *env, uint32_t function, int reg) > +{ > + struct kvm_cpuid2 *cpuid; > + int i, max; > + uint32_t ret = 0; > + uint32_t cpuid_1_edx; > + > + if (!kvm_check_extension(KVM_CAP_EXT_CPUID)) { > + return -1U; > + kvm_check_extension doesn't exist in upstream QEMU. It's a good idea though so I added it in a previous commit. However, I changed the signature to it to take a KVMState * as the first argument (which is available in env->kvm_state). I updated this patch to pass the extra 's' parameter. Regards, Anthony Liguori
Anthony Liguori wrote: > > kvm_check_extension doesn't exist in upstream QEMU. It's a good idea > though so I added it in a previous commit. However, I changed the > signature to it to take a KVMState * as the first argument (which is > available in env->kvm_state). I updated this patch to pass the extra > 's' parameter. Ah, you had a patch, I just didn't notice in my queue. Still wanted to make the KVMState change though.
Anthony Liguori wrote: > Anthony Liguori wrote: >> >> kvm_check_extension doesn't exist in upstream QEMU. It's a good idea >> though so I added it in a previous commit. However, I changed the >> signature to it to take a KVMState * as the first argument (which is >> available in env->kvm_state). I updated this patch to pass the extra >> 's' parameter. > > Ah, you had a patch, I just didn't notice in my queue. > Yeah, I should have made the dependency explicit. > Still wanted to make the KVMState change though. > I think the KVM_REQUIRE_EXTENSION bit didn't like it.
diff --git a/kvm.h b/kvm.h index bd4e8d4..c134c45 100644 --- a/kvm.h +++ b/kvm.h @@ -124,6 +124,9 @@ void kvm_arch_remove_all_hw_breakpoints(void); void kvm_arch_update_guest_debug(CPUState *env, struct kvm_guest_debug *dbg); +uint32_t kvm_arch_get_supported_cpuid(CPUState *env, uint32_t function, + int reg); + /* generic hooks - to be moved/refactored once there are more users */ static inline void cpu_synchronize_state(CPUState *env, int modified) diff --git a/target-i386/kvm.c b/target-i386/kvm.c index b534b2d..5f54ff5 100644 --- a/target-i386/kvm.c +++ b/target-i386/kvm.c @@ -34,6 +34,86 @@ do { } while (0) #endif +#ifdef KVM_CAP_EXT_CPUID + +static struct kvm_cpuid2 *try_get_cpuid(KVMState *s, int max) +{ + struct kvm_cpuid2 *cpuid; + int r, size; + + size = sizeof(*cpuid) + max * sizeof(*cpuid->entries); + cpuid = (struct kvm_cpuid2 *)qemu_mallocz(size); + cpuid->nent = max; + r = kvm_ioctl(s, KVM_GET_SUPPORTED_CPUID, cpuid); + if (r < 0) { + if (r == -E2BIG) { + qemu_free(cpuid); + return NULL; + } else { + fprintf(stderr, "KVM_GET_SUPPORTED_CPUID failed: %s\n", + strerror(-r)); + exit(1); + } + } + return cpuid; +} + +uint32_t kvm_arch_get_supported_cpuid(CPUState *env, uint32_t function, int reg) +{ + struct kvm_cpuid2 *cpuid; + int i, max; + uint32_t ret = 0; + uint32_t cpuid_1_edx; + + if (!kvm_check_extension(KVM_CAP_EXT_CPUID)) { + return -1U; + } + + max = 1; + while ((cpuid = try_get_cpuid(env->kvm_state, max)) == NULL) { + max *= 2; + } + + for (i = 0; i < cpuid->nent; ++i) { + if (cpuid->entries[i].function == function) { + switch (reg) { + case R_EAX: + ret = cpuid->entries[i].eax; + break; + case R_EBX: + ret = cpuid->entries[i].ebx; + break; + case R_ECX: + ret = cpuid->entries[i].ecx; + break; + case R_EDX: + ret = cpuid->entries[i].edx; + if (function == 0x80000001) { + /* On Intel, kvm returns cpuid according to the Intel spec, + * so add missing bits according to the AMD spec: + */ + cpuid_1_edx = kvm_arch_get_supported_cpuid(env, 1, R_EDX); + ret |= cpuid_1_edx & 0xdfeff7ff; + } + break; + } + } + } + + qemu_free(cpuid); + + return ret; +} + +#else + +uint32_t kvm_arch_get_supported_cpuid(CPUState *env, uint32_t function, int reg) +{ + return -1U; +} + +#endif + int kvm_arch_init_vcpu(CPUState *env) { struct {
kvm does not support all cpu features; add support for dunamically querying the supported feature set. Signed-off-by: Avi Kivity <avi@redhat.com> --- kvm.h | 3 ++ target-i386/kvm.c | 80 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 83 insertions(+), 0 deletions(-)