| Message ID | 20220301143650.143749-7-mlevitsk@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | nSVM/SVM features | expand |
On 3/1/22 15:36, Maxim Levitsky wrote: > Apparently on some systems AVIC is disabled in CPUID but still usable. > > Allow the user to override the CPUID if the user is willing to > take the risk. > > Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> > --- > arch/x86/kvm/svm/svm.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c > index 776585dd77769..a26b4c899899e 100644 > --- a/arch/x86/kvm/svm/svm.c > +++ b/arch/x86/kvm/svm/svm.c > @@ -202,6 +202,9 @@ module_param(tsc_scaling, int, 0444); > static bool avic; > module_param(avic, bool, 0444); > > +static bool force_avic; > +module_param_unsafe(force_avic, bool, 0444); > + > bool __read_mostly dump_invalid_vmcb; > module_param(dump_invalid_vmcb, bool, 0644); > > @@ -4896,10 +4899,14 @@ static __init int svm_hardware_setup(void) > nrips = false; > } > > - enable_apicv = avic = avic && npt_enabled && boot_cpu_has(X86_FEATURE_AVIC); > + enable_apicv = avic = avic && npt_enabled && (boot_cpu_has(X86_FEATURE_AVIC) || force_avic); > > if (enable_apicv) { > - pr_info("AVIC enabled\n"); > + if (!boot_cpu_has(X86_FEATURE_AVIC)) { > + pr_warn("AVIC is not supported in CPUID but force enabled"); > + pr_warn("Your system might crash and burn"); > + } else > + pr_info("AVIC enabled\n"); > > amd_iommu_register_ga_log_notifier(&avic_ga_log_notifier); > } else { Queued, thanks. Paolo
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c index 776585dd77769..a26b4c899899e 100644 --- a/arch/x86/kvm/svm/svm.c +++ b/arch/x86/kvm/svm/svm.c @@ -202,6 +202,9 @@ module_param(tsc_scaling, int, 0444); static bool avic; module_param(avic, bool, 0444); +static bool force_avic; +module_param_unsafe(force_avic, bool, 0444); + bool __read_mostly dump_invalid_vmcb; module_param(dump_invalid_vmcb, bool, 0644); @@ -4896,10 +4899,14 @@ static __init int svm_hardware_setup(void) nrips = false; } - enable_apicv = avic = avic && npt_enabled && boot_cpu_has(X86_FEATURE_AVIC); + enable_apicv = avic = avic && npt_enabled && (boot_cpu_has(X86_FEATURE_AVIC) || force_avic); if (enable_apicv) { - pr_info("AVIC enabled\n"); + if (!boot_cpu_has(X86_FEATURE_AVIC)) { + pr_warn("AVIC is not supported in CPUID but force enabled"); + pr_warn("Your system might crash and burn"); + } else + pr_info("AVIC enabled\n"); amd_iommu_register_ga_log_notifier(&avic_ga_log_notifier); } else {
Apparently on some systems AVIC is disabled in CPUID but still usable. Allow the user to override the CPUID if the user is willing to take the risk. Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> --- arch/x86/kvm/svm/svm.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)