[SRU][J][PATCH 2/3] x86/CPU/AMD: Add ZenX generations flags

[Juerg Haefliger]

From: "Borislav Petkov (AMD)" <bp at alien8.de>

Add X86_FEATURE flags for each Zen generation. They should be used from
now on instead of checking f/m/s.

Signed-off-by: Borislav Petkov (AMD) <bp at alien8.de>
Reviewed-by: Nikolay Borisov <nik.borisov at suse.com>
Acked-by: Thomas Gleixner <tglx at linutronix.de>
Link: http://lore.kernel.org/r/20231120104152.13740-2-bp@alien8.de
(backported from commit 30fa92832f405d5ac9f263e99f62445fa3084008)
[juergh: Adjusted context due to commit:
 5ddc772dcbbb ("x86/CPU/AMD: Properly check the TSA microcode")]
CVE-2024-53114
Signed-off-by: Juerg Haefliger <juerg.haefliger at canonical.com>
---
 arch/x86/include/asm/cpufeatures.h |  5 ++-
 arch/x86/kernel/cpu/amd.c          | 70 +++++++++++++++++++++++++++++-
 2 files changed, 72 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index cb33976d03c0..2a5dc56874a4 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -219,7 +219,7 @@
 #define X86_FEATURE_IBRS		( 7*32+25) /* Indirect Branch Restricted Speculation */
 #define X86_FEATURE_IBPB		( 7*32+26) /* "ibpb" Indirect Branch Prediction Barrier without a guaranteed RSB flush */
 #define X86_FEATURE_STIBP		( 7*32+27) /* Single Thread Indirect Branch Predictors */
-#define X86_FEATURE_ZEN			(7*32+28) /* "" CPU based on Zen microarchitecture */
+#define X86_FEATURE_ZEN			( 7*32+28) /* "" CPU based on Zen microarchitecture */
 #define X86_FEATURE_L1TF_PTEINV		( 7*32+29) /* "" L1TF workaround PTE inversion */
 #define X86_FEATURE_IBRS_ENHANCED	( 7*32+30) /* Enhanced IBRS */
 #define X86_FEATURE_MSR_IA32_FEAT_CTL	( 7*32+31) /* "" MSR IA32_FEAT_CTL configured */
@@ -311,6 +311,9 @@
 #define X86_FEATURE_SRSO_ALIAS		(11*32+25) /* "" AMD BTB untrain RETs through aliasing */
 #define X86_FEATURE_IBPB_ON_VMEXIT	(11*32+26) /* "" Issue an IBPB only on VMEXIT */
 #define X86_FEATURE_APIC_MSRS_FENCE	(11*32+27) /* "" IA32_TSC_DEADLINE and X2APIC MSRs need fencing */
+#define X86_FEATURE_ZEN2		(11*32+28) /* "" CPU based on Zen2 microarchitecture */
+#define X86_FEATURE_ZEN3		(11*32+29) /* "" CPU based on Zen3 microarchitecture */
+#define X86_FEATURE_ZEN4		(11*32+30) /* "" CPU based on Zen4 microarchitecture */
 
 /* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */
 #define X86_FEATURE_AVX_VNNI		(12*32+ 4) /* AVX VNNI instructions */
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index b29fa3b0eb23..9399defbf173 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -680,7 +680,50 @@ static void bsp_init_amd(struct cpuinfo_x86 *c)
 
 	resctrl_cpu_detect(c);
 
+	/* Figure out Zen generations: */
+	switch (c->x86) {
+	case 0x17: {
+		switch (c->x86_model) {
+		case 0x00 ... 0x2f:
+		case 0x50 ... 0x5f:
+			setup_force_cpu_cap(X86_FEATURE_ZEN);
+			break;
+		case 0x30 ... 0x4f:
+		case 0x60 ... 0x7f:
+		case 0x90 ... 0x91:
+		case 0xa0 ... 0xaf:
+			setup_force_cpu_cap(X86_FEATURE_ZEN2);
+			break;
+		default:
+			goto warn;
+		}
+		break;
+	}
+	case 0x19: {
+		switch (c->x86_model) {
+		case 0x00 ... 0x0f:
+		case 0x20 ... 0x5f:
+			setup_force_cpu_cap(X86_FEATURE_ZEN3);
+			break;
+		case 0x10 ... 0x1f:
+		case 0x60 ... 0xaf:
+			setup_force_cpu_cap(X86_FEATURE_ZEN4);
+			break;
+		default:
+			goto warn;
+		}
+		break;
+	}
+	default:
+		break;
+	}
+
 	tsa_init(c);
+
+	return;
+
+warn:
+	WARN_ONCE(1, "Family 0x%x, model: 0x%x??\n", c->x86, c->x86_model);
 }
 
 static void early_detect_mem_encrypt(struct cpuinfo_x86 *c)
@@ -1038,8 +1081,6 @@ void init_spectral_chicken(struct cpuinfo_x86 *c)
 
 static void init_amd_zn(struct cpuinfo_x86 *c)
 {
-	set_cpu_cap(c, X86_FEATURE_ZEN);
-
 #ifdef CONFIG_NUMA
 	node_reclaim_distance = 32;
 #endif
@@ -1102,6 +1143,22 @@ static void zenbleed_check(struct cpuinfo_x86 *c)
 	}
 }
 
+static void init_amd_zen(struct cpuinfo_x86 *c)
+{
+}
+
+static void init_amd_zen2(struct cpuinfo_x86 *c)
+{
+}
+
+static void init_amd_zen3(struct cpuinfo_x86 *c)
+{
+}
+
+static void init_amd_zen4(struct cpuinfo_x86 *c)
+{
+}
+
 static void init_amd(struct cpuinfo_x86 *c)
 {
 	early_init_amd(c);
@@ -1136,6 +1193,15 @@ static void init_amd(struct cpuinfo_x86 *c)
 	case 0x19: init_amd_zn(c); break;
 	}
 
+	if (boot_cpu_has(X86_FEATURE_ZEN))
+		init_amd_zen(c);
+	else if (boot_cpu_has(X86_FEATURE_ZEN2))
+		init_amd_zen2(c);
+	else if (boot_cpu_has(X86_FEATURE_ZEN3))
+		init_amd_zen3(c);
+	else if (boot_cpu_has(X86_FEATURE_ZEN4))
+		init_amd_zen4(c);
+
 	/*
 	 * Enable workaround for FXSAVE leak on CPUs
 	 * without a XSaveErPtr feature
-- 
2.48.1