[tip: x86/cpu] x86/cpu: X86_FEATURE_INTEL_PPIN finally has a CPUID bit

From: tip-bot2 for Tony Luck
Date: Wed Feb 02 2022 - 01:54:00 EST


The following commit has been merged into the x86/cpu branch of tip:

Commit-ID: 00a2f23eef7d1fa6c2dfdc613857b84fbf5e2b3b
Gitweb: https://git.kernel.org/tip/00a2f23eef7d1fa6c2dfdc613857b84fbf5e2b3b
Author: Tony Luck <tony.luck@xxxxxxxxx>
AuthorDate: Mon, 31 Jan 2022 15:01:08 -08:00
Committer: Borislav Petkov <bp@xxxxxxx>
CommitterDate: Tue, 01 Feb 2022 16:15:19 +01:00

x86/cpu: X86_FEATURE_INTEL_PPIN finally has a CPUID bit

After nine generations of adding to model specific list of CPUs that
support PPIN (Protected Processor Inventory Number) Intel allocated
a CPUID bit to enumerate the MSRs.

CPUID(EAX=7, ECX=1).EBX bit 0 enumerates presence of MSR_PPIN_CTL and
MSR_PPIN. Add it to the "scattered" CPUID bits and add an entry to the
ppin_cpuids[] x86_match_cpu() array to catch Intel CPUs that implement
it.

Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Borislav Petkov <bp@xxxxxxx>
Link: https://lore.kernel.org/r/20220131230111.2004669-3-tony.luck@xxxxxxxxx
---
arch/x86/kernel/cpu/common.c | 1 +
arch/x86/kernel/cpu/scattered.c | 1 +
2 files changed, 2 insertions(+)

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index b0bd8a6..0681c69 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -104,6 +104,7 @@ static struct ppin_info {

static const struct x86_cpu_id ppin_cpuids[] = {
X86_MATCH_FEATURE(X86_FEATURE_AMD_PPIN, &ppin_info[X86_VENDOR_AMD]),
+ X86_MATCH_FEATURE(X86_FEATURE_INTEL_PPIN, &ppin_info[X86_VENDOR_INTEL]),

/* Legacy models without CPUID enumeration */
X86_MATCH_INTEL_FAM6_MODEL(IVYBRIDGE_X, &ppin_info[X86_VENDOR_INTEL]),
diff --git a/arch/x86/kernel/cpu/scattered.c b/arch/x86/kernel/cpu/scattered.c
index 21d1f06..4143b1e 100644
--- a/arch/x86/kernel/cpu/scattered.c
+++ b/arch/x86/kernel/cpu/scattered.c
@@ -26,6 +26,7 @@ struct cpuid_bit {
static const struct cpuid_bit cpuid_bits[] = {
{ X86_FEATURE_APERFMPERF, CPUID_ECX, 0, 0x00000006, 0 },
{ X86_FEATURE_EPB, CPUID_ECX, 3, 0x00000006, 0 },
+ { X86_FEATURE_INTEL_PPIN, CPUID_EBX, 0, 0x00000007, 1 },
{ X86_FEATURE_CQM_LLC, CPUID_EDX, 1, 0x0000000f, 0 },
{ X86_FEATURE_CQM_OCCUP_LLC, CPUID_EDX, 0, 0x0000000f, 1 },
{ X86_FEATURE_CQM_MBM_TOTAL, CPUID_EDX, 1, 0x0000000f, 1 },