| Message ID | 20240617-add-cpu-type-v1-9-b88998c01e76@linux.intel.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | Add CPU-type to topology | expand |
On 17/06/2024 10:12 am, Pawan Gupta wrote: > diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c > index 7e3b09b0f82c..73ec66321758 100644 > --- a/arch/x86/kernel/cpu/common.c > +++ b/arch/x86/kernel/cpu/common.c > @@ -1209,6 +1209,9 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = { > #define VULNBL_INTEL_STEPPINGS(vfm, steppings, issues) \ > X86_MATCH_VFM_STEPPINGS(INTEL_##vfm, steppings, issues) > > +#define VULNBL_INTEL_CPU_TYPE(vfm, cpu_type, issues) \ > + X86_MATCH_VFM_CPU_TYPE(INTEL_##vfm, cpu_type, issues) > + > #define VULNBL_AMD(family, blacklist) \ > VULNBL(AMD, family, X86_MODEL_ANY, blacklist) > > @@ -1255,9 +1258,7 @@ static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = { > VULNBL_INTEL(TIGERLAKE, GDS), > VULNBL_INTEL(LAKEFIELD, MMIO | MMIO_SBDS | RETBLEED), > VULNBL_INTEL(ROCKETLAKE, MMIO | RETBLEED | GDS), > - VULNBL_INTEL(ALDERLAKE, RFDS), > VULNBL_INTEL(ALDERLAKE_L, RFDS), > - VULNBL_INTEL(RAPTORLAKE, RFDS), > VULNBL_INTEL(RAPTORLAKE_P, RFDS), > VULNBL_INTEL(RAPTORLAKE_S, RFDS), > VULNBL_INTEL(ATOM_GRACEMONT, RFDS), > @@ -1271,6 +1272,8 @@ static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = { > /* Match more than Vendor/Family/Model */ > VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x0, 0x0), MMIO | RETBLEED), > VULNBL_INTEL (COMETLAKE_L, MMIO | MMIO_SBDS | RETBLEED | GDS), > + VULNBL_INTEL_CPU_TYPE (RAPTORLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), > + VULNBL_INTEL_CPU_TYPE (ALDERLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), How does this work? Being __initconst, this is only evaluated on the BSP. P-only and mixed P/E systems won't see X86_CPU_TYPE_INTEL_ATOM, even if there are ATOM APs to bring up later. ~Andrew
On 6/17/24 02:12, Pawan Gupta wrote: > +#define VULNBL_INTEL_CPU_TYPE(vfm, cpu_type, issues) \ > + X86_MATCH_VFM_CPU_TYPE(INTEL_##vfm, cpu_type, issues) > + ... > /* Match more than Vendor/Family/Model */ > VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x0, 0x0), MMIO | RETBLEED), > VULNBL_INTEL (COMETLAKE_L, MMIO | MMIO_SBDS | RETBLEED | GDS), > + VULNBL_INTEL_CPU_TYPE (RAPTORLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), > + VULNBL_INTEL_CPU_TYPE (ALDERLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), Could we tweak this a bit to make it more compact? For instance, if we did this: #define VULNBL_INTEL_TYPE(vfm, cpu_type, issues) \ X86_MATCH_VFM_CPU_TYPE(INTEL_##vfm, \ X86_CPU_TYPE_INTEL_##cpu_type, \ issues) We'd end up with entries like this: VULNBL_INTEL_TYPE (ALDERLAKE, ATOM, RFDS), I guess "TYPE" is a _bit_ ambiguous. But it's also pretty patently obvious what's going on versus something like this: VULNBL_INTEL (COMETLAKE_L, MMIO | MMIO_SBDS | RETBLEED...), Getting rid of the "X86_CPU_TYPE_INTEL_" string in the table is low hanging fruit. I don't feel as strongly about changing the new macro name.
On 6/17/24 02:43, Andrew Cooper wrote: > On 17/06/2024 10:12 am, Pawan Gupta wrote: >> + VULNBL_INTEL_CPU_TYPE (RAPTORLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), >> + VULNBL_INTEL_CPU_TYPE (ALDERLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), > > How does this work? > > Being __initconst, this is only evaluated on the BSP. > > P-only and mixed P/E systems won't see X86_CPU_TYPE_INTEL_ATOM, even if > there are ATOM APs to bring up later. The X86_CPU_TYPE_* is only used on the boot CPU on non-hybrids. Hybrids (independent of the boot CPU type) should be considered vulnerable no matter what.
On Mon, Jun 17, 2024 at 07:34:22AM -0700, Dave Hansen wrote: > On 6/17/24 02:43, Andrew Cooper wrote: > > On 17/06/2024 10:12 am, Pawan Gupta wrote: > >> + VULNBL_INTEL_CPU_TYPE (RAPTORLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), > >> + VULNBL_INTEL_CPU_TYPE (ALDERLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), > > > > How does this work? > > > > Being __initconst, this is only evaluated on the BSP. > > > > P-only and mixed P/E systems won't see X86_CPU_TYPE_INTEL_ATOM, even if > > there are ATOM APs to bring up later. > > The X86_CPU_TYPE_* is only used on the boot CPU on non-hybrids. Hybrids > (independent of the boot CPU type) should be considered vulnerable no > matter what. Yes. This is done in x86_match_cpu_type(), that matches all cpu-types on hybrids: static bool x86_match_cpu_type(struct cpuinfo_x86 *c, const struct x86_cpu_id) { if (m->cpu_type == X86_CPU_TYPE_ANY) return true; /* Hybrid CPUs are special, they are assumed to match all cpu-types */ if (boot_cpu_has(X86_FEATURE_HYBRID_CPU)) return true; return c->topo.cpu_type == m->cpu_type; }
On Mon, Jun 17, 2024 at 07:33:13AM -0700, Dave Hansen wrote: > On 6/17/24 02:12, Pawan Gupta wrote: > > +#define VULNBL_INTEL_CPU_TYPE(vfm, cpu_type, issues) \ > > + X86_MATCH_VFM_CPU_TYPE(INTEL_##vfm, cpu_type, issues) > > + > ... > > /* Match more than Vendor/Family/Model */ > > VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x0, 0x0), MMIO | RETBLEED), > > VULNBL_INTEL (COMETLAKE_L, MMIO | MMIO_SBDS | RETBLEED | GDS), > > + VULNBL_INTEL_CPU_TYPE (RAPTORLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), > > + VULNBL_INTEL_CPU_TYPE (ALDERLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), > > Could we tweak this a bit to make it more compact? For instance, if we > did this: > > #define VULNBL_INTEL_TYPE(vfm, cpu_type, issues) \ > X86_MATCH_VFM_CPU_TYPE(INTEL_##vfm, \ > X86_CPU_TYPE_INTEL_##cpu_type, \ > issues) > > We'd end up with entries like this: > > VULNBL_INTEL_TYPE (ALDERLAKE, ATOM, RFDS), > > I guess "TYPE" is a _bit_ ambiguous. But it's also pretty patently > obvious what's going on versus something like this: > > VULNBL_INTEL (COMETLAKE_L, MMIO | MMIO_SBDS | RETBLEED...), > > Getting rid of the "X86_CPU_TYPE_INTEL_" string in the table is low > hanging fruit. I don't feel as strongly about changing the new macro name. It makes sense to me, atleast getting rid of X86_CPU_TYPE_INTEL_ in X86_CPU_TYPE_INTEL_ATOM.
diff --git a/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst b/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst index 0585d02b9a6c..ad15417d39f9 100644 --- a/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst +++ b/Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst @@ -29,14 +29,6 @@ Below is the list of affected Intel processors [#f1]_: RAPTORLAKE_S 06_BFH =================== ============ -As an exception to this table, Intel Xeon E family parts ALDERLAKE(06_97H) and -RAPTORLAKE(06_B7H) codenamed Catlow are not affected. They are reported as -vulnerable in Linux because they share the same family/model with an affected -part. Unlike their affected counterparts, they do not enumerate RFDS_CLEAR or -CPUID.HYBRID. This information could be used to distinguish between the -affected and unaffected parts, but it is deemed not worth adding complexity as -the reporting is fixed automatically when these parts enumerate RFDS_NO. - Mitigation ========== Intel released a microcode update that enables software to clear sensitive diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index 7e3b09b0f82c..73ec66321758 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1209,6 +1209,9 @@ static const __initconst struct x86_cpu_id cpu_vuln_whitelist[] = { #define VULNBL_INTEL_STEPPINGS(vfm, steppings, issues) \ X86_MATCH_VFM_STEPPINGS(INTEL_##vfm, steppings, issues) +#define VULNBL_INTEL_CPU_TYPE(vfm, cpu_type, issues) \ + X86_MATCH_VFM_CPU_TYPE(INTEL_##vfm, cpu_type, issues) + #define VULNBL_AMD(family, blacklist) \ VULNBL(AMD, family, X86_MODEL_ANY, blacklist) @@ -1255,9 +1258,7 @@ static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = { VULNBL_INTEL(TIGERLAKE, GDS), VULNBL_INTEL(LAKEFIELD, MMIO | MMIO_SBDS | RETBLEED), VULNBL_INTEL(ROCKETLAKE, MMIO | RETBLEED | GDS), - VULNBL_INTEL(ALDERLAKE, RFDS), VULNBL_INTEL(ALDERLAKE_L, RFDS), - VULNBL_INTEL(RAPTORLAKE, RFDS), VULNBL_INTEL(RAPTORLAKE_P, RFDS), VULNBL_INTEL(RAPTORLAKE_S, RFDS), VULNBL_INTEL(ATOM_GRACEMONT, RFDS), @@ -1271,6 +1272,8 @@ static const struct x86_cpu_id cpu_vuln_blacklist[] __initconst = { /* Match more than Vendor/Family/Model */ VULNBL_INTEL_STEPPINGS(COMETLAKE_L, X86_STEPPINGS(0x0, 0x0), MMIO | RETBLEED), VULNBL_INTEL (COMETLAKE_L, MMIO | MMIO_SBDS | RETBLEED | GDS), + VULNBL_INTEL_CPU_TYPE (RAPTORLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), + VULNBL_INTEL_CPU_TYPE (ALDERLAKE, X86_CPU_TYPE_INTEL_ATOM, RFDS), VULNBL_AMD(0x15, RETBLEED), VULNBL_AMD(0x16, RETBLEED),
RFDS only affects Atom parts. Vendor/Family/Model matching in the affected processor table makes Alderlake and Raptorlake P-only parts affected (which are not affected in reality). This is because the affected hybrid and E-only parts have the same Family/Model as the unaffected P-only parts. Match CPU-type as Atom to exclude P-only parts as RFDS affected. Note, a guest with the same Family/Model as the affected part may not have leaf 1A enumerated to know its CPU-type, but it should not be a problem as guest's Family/Model can anyways be inaccurate. Moreover, RFDS_NO or RFDS_CLEAR enumeration by the VMM decides the affected status of the guest. Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> --- Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst | 8 -------- arch/x86/kernel/cpu/common.c | 7 +++++-- 2 files changed, 5 insertions(+), 10 deletions(-)