Merge tag 'x86-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:

 - Fix MCE timer reinit locking

 - Fix/improve CoCo guest random entropy pool init

 - Fix SEV-SNP late disable bugs

 - Fix false positive objtool build warning

 - Fix header dependency bug

 - Fix resctrl CPU offlining bug

* tag 'x86-urgent-2024-04-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/retpoline: Add NOENDBR annotation to the SRSO dummy return thunk
  x86/mce: Make sure to grab mce_sysfs_mutex in set_bank()
  x86/CPU/AMD: Track SNP host status with cc_platform_*()
  x86/cc: Add cc_platform_set/_clear() helpers
  x86/kvm/Kconfig: Have KVM_AMD_SEV select ARCH_HAS_CC_PLATFORM
  x86/coco: Require seeding RNG with RDRAND on CoCo systems
  x86/numa/32: Include missing <asm/pgtable_areas.h>
  x86/resctrl: Fix uninitialized memory read when last CPU of domain goes offline

1 files changed, 23 insertions, 15 deletions

diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index 6d8677e80ddb..9bf17c9c29da 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -345,6 +345,28 @@ static void srat_detect_node(struct cpuinfo_x86 *c)
 #endif
 }
 
+static void bsp_determine_snp(struct cpuinfo_x86 *c)
+{
+#ifdef CONFIG_ARCH_HAS_CC_PLATFORM
+	cc_vendor = CC_VENDOR_AMD;
+
+	if (cpu_has(c, X86_FEATURE_SEV_SNP)) {
+		/*
+		 * RMP table entry format is not architectural and is defined by the
+		 * per-processor PPR. Restrict SNP support on the known CPU models
+		 * for which the RMP table entry format is currently defined for.
+		 */
+		if (!cpu_has(c, X86_FEATURE_HYPERVISOR) &&
+		    c->x86 >= 0x19 && snp_probe_rmptable_info()) {
+			cc_platform_set(CC_ATTR_HOST_SEV_SNP);
+		} else {
+			setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
+			cc_platform_clear(CC_ATTR_HOST_SEV_SNP);
+		}
+	}
+#endif
+}
+
 static void bsp_init_amd(struct cpuinfo_x86 *c)
 {
 	if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) {
@@ -452,21 +474,7 @@ static void bsp_init_amd(struct cpuinfo_x86 *c)
 		break;
 	}
 
-	if (cpu_has(c, X86_FEATURE_SEV_SNP)) {
-		/*
-		 * RMP table entry format is not architectural and it can vary by processor
-		 * and is defined by the per-processor PPR. Restrict SNP support on the
-		 * known CPU model and family for which the RMP table entry format is
-		 * currently defined for.
-		 */
-		if (!boot_cpu_has(X86_FEATURE_ZEN3) &&
-		    !boot_cpu_has(X86_FEATURE_ZEN4) &&
-		    !boot_cpu_has(X86_FEATURE_ZEN5))
-			setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
-		else if (!snp_probe_rmptable_info())
-			setup_clear_cpu_cap(X86_FEATURE_SEV_SNP);
-	}
-
+	bsp_determine_snp(c);
 	return;
 
 warn: