On 23/12/2020 20:32, Igor Druzhinin wrote: > LBR, C-state MSRs should correspond to Ice Lake desktop according to > External Design Specification vol.2 for both models. > > Ice Lake-X is known to expose IF_PSCHANGE_MC_NO in IA32_ARCH_CAPABILITIES MSR > (confirmed on Whitley SDP) which means the erratum is fixed in hardware for > that model and therefore it shouldn't be present in has_if_pschange_mc list. > Provisionally assume the same to be the case for Ice Lake-D. > > Signed-off-by: Igor Druzhinin <igor.druzhi...@citrix.com> > --- > Changes in v3: > - Add Ice Lake-D model numbers > - Drop has_if_pschange_mc hunk following Tiger Lake related discussion - > IF_PSCHANGE_MC_NO is confimed to be exposed on Whitley SDP > > --- > xen/arch/x86/acpi/cpu_idle.c | 2 ++ > xen/arch/x86/hvm/vmx/vmx.c | 2 +- > 2 files changed, 3 insertions(+), 1 deletion(-) > > diff --git a/xen/arch/x86/acpi/cpu_idle.c b/xen/arch/x86/acpi/cpu_idle.c > index c092086..d788c8b 100644 > --- a/xen/arch/x86/acpi/cpu_idle.c > +++ b/xen/arch/x86/acpi/cpu_idle.c > @@ -181,6 +181,8 @@ static void do_get_hw_residencies(void *arg) > case 0x55: > case 0x5E: > /* Ice Lake */ > + case 0x6A: > + case 0x6C: > case 0x7D: > case 0x7E: > /* Tiger Lake */
So I think these changes are correct. TGL definitely has deeper core/package states than this interface enumerates, but I can't locate extra MSRs. > diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c > index 2d4475e..bff5979 100644 > --- a/xen/arch/x86/hvm/vmx/vmx.c > +++ b/xen/arch/x86/hvm/vmx/vmx.c > @@ -2775,7 +2775,7 @@ static const struct lbr_info *last_branch_msr_get(void) > /* Goldmont Plus */ > case 0x7a: > /* Ice Lake */ > - case 0x7d: case 0x7e: > + case 0x6a: case 0x6c: case 0x7d: case 0x7e: IceLake Server has what appear to be new aspects to LBR. I can't find LAST_INT_INFO (0x1e0) existing in any previous generation. However, my investigation also found LBR_SELECT which has been around since Nehalem, which we don't handle, and Linux *does* use. This logic is in a terrible state. It's no surprise it is always the first thing to break in the field. ~Andrew
