| Message ID | 20151112101317.GA3649@pd.tnic (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 12/11/2015 11:13, Borislav Petkov wrote: > Hey Paolo, > > do we apply stuff like that below? If we really need to, we do. > When booting guests all the time here, dmesg gets filled up with those > "unhandled rdmsr" useless warnings. The patch below shuts them up. > > The only problem is that the IC CFG MSR has those fields > defined starting from F15h and I don't see a way to check the > family/model/stepping of the guest CPU in kvm. Is there? Yes, see guest_cpuid_has_* for an example of reading the CPUID values. But if it's defined for _all_ models starting at family 21, we can just do it unconditionally. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Nov 12, 2015 at 11:33:33AM +0100, Paolo Bonzini wrote: > Yes, see guest_cpuid_has_* for an example of reading the CPUID values. > > But if it's defined for _all_ models starting at family 21, we can just > do it unconditionally. The thing is, those bits are Reserved again on the next family 22. Lemme take a look at guest_cpuid_has_* and see how ugly it gets. Thanks.
On Thu, Nov 12, 2015 at 11:59:58AM +0100, Borislav Petkov wrote: > On Thu, Nov 12, 2015 at 11:33:33AM +0100, Paolo Bonzini wrote: > > Yes, see guest_cpuid_has_* for an example of reading the CPUID values. > > > > But if it's defined for _all_ models starting at family 21, we can just > > do it unconditionally. > > The thing is, those bits are Reserved again on the next family 22. Lemme > take a look at guest_cpuid_has_* and see how ugly it gets. Ok, I see there's guest_cpuid_is_amd() but I'd need also family and model. How about adding also guest_cpuid_family(), guest_cpuid_model(), guest_cpuid_stepping()? Those could be quite useful in other contexts maybe. Or, I can do a single function which simply returns CPUID_1_EAX of the guest vcpu and caller can then pick stuff apart... Thoughts?
On 12/11/2015 13:16, Borislav Petkov wrote: >>> > > Yes, see guest_cpuid_has_* for an example of reading the CPUID values. >>> > > >>> > > But if it's defined for _all_ models starting at family 21, we can just >>> > > do it unconditionally. >> > >> > The thing is, those bits are Reserved again on the next family 22. Lemme >> > take a look at guest_cpuid_has_* and see how ugly it gets. > > Ok, I see there's guest_cpuid_is_amd() but I'd need also family and model. > > How about adding also > > guest_cpuid_family(), guest_cpuid_model(), guest_cpuid_stepping()? Those > could be quite useful in other contexts maybe. Sure, that's what I meant by "for an example". :) Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index b8c14bb7fc8f..08b880818fb9 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -315,6 +315,7 @@ #define MSR_F15H_PERF_CTR 0xc0010201 #define MSR_F15H_NB_PERF_CTL 0xc0010240 #define MSR_F15H_NB_PERF_CTR 0xc0010241 +#define MSR_F15H_IC_CFG 0xc0011021 /* Fam 10h MSRs */ #define MSR_FAM10H_MMIO_CONF_BASE 0xc0010058 diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 4a70fc6d400a..1d76dcdf7e55 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -665,9 +665,9 @@ static void init_amd_bd(struct cpuinfo_x86 *c) * Disable it on the affected CPUs. */ if ((c->x86_model >= 0x02) && (c->x86_model < 0x20)) { - if (!rdmsrl_safe(0xc0011021, &value) && !(value & 0x1E)) { + if (!rdmsrl_safe(MSR_F15H_IC_CFG, &value) && !(value & 0x1E)) { value |= 0x1E; - wrmsrl_safe(0xc0011021, value); + wrmsrl_safe(MSR_F15H_IC_CFG, value); } } } diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 2f9ed1ff0632..7948cdeacbfe 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -3141,6 +3141,9 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) case MSR_IA32_UCODE_REV: msr_info->data = 0x01000065; break; + case MSR_F15H_IC_CFG: + msr_info->data = 0x1E; + break; default: return kvm_get_msr_common(vcpu, msr_info); }