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authorWei Huang <wei.huang2@amd.com>2020-03-21 14:38:00 -0500
committerBorislav Petkov <bp@suse.de>2020-03-22 11:03:47 +0100
commit077168e241ec5a3b273652acb1e85f8bc1dc2d81 (patch)
treed04952d6ceed16ac88321c282374cbdac6314571 /arch/x86
parentd8ecca4043f2d9d89daab7915eca8c2ec6254d0f (diff)
x86/mce/amd: Add PPIN support for AMD MCE
Newer AMD CPUs support a feature called protected processor identification number (PPIN). This feature can be detected via CPUID_Fn80000008_EBX[23]. However, CPUID alone is not enough to read the processor identification number - MSR_AMD_PPIN_CTL also needs to be configured properly. If, for any reason, MSR_AMD_PPIN_CTL[PPIN_EN] can not be turned on, such as disabled in BIOS, the CPU capability bit X86_FEATURE_AMD_PPIN needs to be cleared. When the X86_FEATURE_AMD_PPIN capability is available, the identification number is issued together with the MCE error info in order to keep track of the source of MCE errors. [ bp: Massage. ] Co-developed-by: Smita Koralahalli Channabasappa <smita.koralahallichannabasappa@amd.com> Signed-off-by: Smita Koralahalli Channabasappa <smita.koralahallichannabasappa@amd.com> Signed-off-by: Wei Huang <wei.huang2@amd.com> Signed-off-by: Borislav Petkov <bp@suse.de> Acked-by: Tony Luck <tony.luck@intel.com> Link: https://lkml.kernel.org/r/20200321193800.3666964-1-wei.huang2@amd.com
Diffstat (limited to 'arch/x86')
-rw-r--r--arch/x86/include/asm/cpufeatures.h1
-rw-r--r--arch/x86/kernel/cpu/amd.c30
-rw-r--r--arch/x86/kernel/cpu/mce/core.c2
3 files changed, 33 insertions, 0 deletions
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index f3327cb56edf..4b263ffb793b 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -299,6 +299,7 @@
#define X86_FEATURE_AMD_IBRS (13*32+14) /* "" Indirect Branch Restricted Speculation */
#define X86_FEATURE_AMD_STIBP (13*32+15) /* "" Single Thread Indirect Branch Predictors */
#define X86_FEATURE_AMD_STIBP_ALWAYS_ON (13*32+17) /* "" Single Thread Indirect Branch Predictors always-on preferred */
+#define X86_FEATURE_AMD_PPIN (13*32+23) /* Protected Processor Inventory Number */
#define X86_FEATURE_AMD_SSBD (13*32+24) /* "" Speculative Store Bypass Disable */
#define X86_FEATURE_VIRT_SSBD (13*32+25) /* Virtualized Speculative Store Bypass Disable */
#define X86_FEATURE_AMD_SSB_NO (13*32+26) /* "" Speculative Store Bypass is fixed in hardware. */
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index ac83a0fef628..a2cd870af7f5 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -393,6 +393,35 @@ static void amd_detect_cmp(struct cpuinfo_x86 *c)
per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
}
+static void amd_detect_ppin(struct cpuinfo_x86 *c)
+{
+ unsigned long long val;
+
+ if (!cpu_has(c, X86_FEATURE_AMD_PPIN))
+ return;
+
+ /* When PPIN is defined in CPUID, still need to check PPIN_CTL MSR */
+ if (rdmsrl_safe(MSR_AMD_PPIN_CTL, &val))
+ goto clear_ppin;
+
+ /* PPIN is locked in disabled mode, clear feature bit */
+ if ((val & 3UL) == 1UL)
+ goto clear_ppin;
+
+ /* If PPIN is disabled, try to enable it */
+ if (!(val & 2UL)) {
+ wrmsrl_safe(MSR_AMD_PPIN_CTL, val | 2UL);
+ rdmsrl_safe(MSR_AMD_PPIN_CTL, &val);
+ }
+
+ /* If PPIN_EN bit is 1, return from here; otherwise fall through */
+ if (val & 2UL)
+ return;
+
+clear_ppin:
+ clear_cpu_cap(c, X86_FEATURE_AMD_PPIN);
+}
+
u16 amd_get_nb_id(int cpu)
{
return per_cpu(cpu_llc_id, cpu);
@@ -940,6 +969,7 @@ static void init_amd(struct cpuinfo_x86 *c)
amd_detect_cmp(c);
amd_get_topology(c);
srat_detect_node(c);
+ amd_detect_ppin(c);
init_amd_cacheinfo(c);
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index fe3983d551cc..dd06fce537fc 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -142,6 +142,8 @@ void mce_setup(struct mce *m)
if (this_cpu_has(X86_FEATURE_INTEL_PPIN))
rdmsrl(MSR_PPIN, m->ppin);
+ else if (this_cpu_has(X86_FEATURE_AMD_PPIN))
+ rdmsrl(MSR_AMD_PPIN, m->ppin);
m->microcode = boot_cpu_data.microcode;
}

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