[PATCH v2 1/6] x86/microcode/core: Move microcode_check() to cpu/microcode/core.c

[Ashok Raj]

microcode_check() is only called from microcode/core.c. Move it and make
it static to prepare for upcoming fix for false negative when checking CPU
features after a microcode update. Also move get_cpu_cap() to processor.h
for general use outside of arch/x86/kernel/cpu/cpu.h

No functional change.

Suggested-by: Alison Schofield <alison.schofield@xxxxxxxxx>
Signed-off-by: Ashok Raj <ashok.raj@xxxxxxxxx>
Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: LKML <linux-kernel@xxxxxxxxxxxxxxx>
Cc: x86 <x86@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: Alison Schofield <alison.schofield@xxxxxxxxx>
Cc: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Tom Lendacky <thomas.lendacky@xxxxxxx>
---
 arch/x86/include/asm/processor.h     |  3 +--
 arch/x86/kernel/cpu/cpu.h            |  1 -
 arch/x86/kernel/cpu/common.c         | 32 ----------------------------
 arch/x86/kernel/cpu/microcode/core.c | 31 +++++++++++++++++++++++++++
 4 files changed, 32 insertions(+), 35 deletions(-)

diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 4e35c66edeb7..70d01ecc39a4 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -182,8 +182,8 @@ extern const struct seq_operations cpuinfo_op;
 
 #define cache_line_size()	(boot_cpu_data.x86_cache_alignment)
 
+extern void get_cpu_cap(struct cpuinfo_x86 *c);
 extern void cpu_detect(struct cpuinfo_x86 *c);
-
 static inline unsigned long long l1tf_pfn_limit(void)
 {
 	return BIT_ULL(boot_cpu_data.x86_cache_bits - 1 - PAGE_SHIFT);
@@ -697,7 +697,6 @@ bool xen_set_default_idle(void);
 #endif
 
 void __noreturn stop_this_cpu(void *dummy);
-void microcode_check(void);
 
 enum l1tf_mitigations {
 	L1TF_MITIGATION_OFF,
diff --git a/arch/x86/kernel/cpu/cpu.h b/arch/x86/kernel/cpu/cpu.h
index 7c9b5893c30a..a142b8d543a3 100644
--- a/arch/x86/kernel/cpu/cpu.h
+++ b/arch/x86/kernel/cpu/cpu.h
@@ -63,7 +63,6 @@ static inline void tsx_ap_init(void) { }
 
 extern void init_spectral_chicken(struct cpuinfo_x86 *c);
 
-extern void get_cpu_cap(struct cpuinfo_x86 *c);
 extern void get_cpu_address_sizes(struct cpuinfo_x86 *c);
 extern void cpu_detect_cache_sizes(struct cpuinfo_x86 *c);
 extern void init_scattered_cpuid_features(struct cpuinfo_x86 *c);
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 9cfca3d7d0e2..7b06034eeddc 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -2296,38 +2296,6 @@ void cpu_init_secondary(void)
 }
 #endif
 
-#ifdef CONFIG_MICROCODE_LATE_LOADING
-/*
- * The microcode loader calls this upon late microcode load to recheck features,
- * only when microcode has been updated. Caller holds microcode_mutex and CPU
- * hotplug lock.
- */
-void microcode_check(void)
-{
-	struct cpuinfo_x86 info;
-
-	perf_check_microcode();
-
-	/* Reload CPUID max function as it might've changed. */
-	info.cpuid_level = cpuid_eax(0);
-
-	/*
-	 * Copy all capability leafs to pick up the synthetic ones so that
-	 * memcmp() below doesn't fail on that. The ones coming from CPUID will
-	 * get overwritten in get_cpu_cap().
-	 */
-	memcpy(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability));
-
-	get_cpu_cap(&info);
-
-	if (!memcmp(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability)))
-		return;
-
-	pr_warn("x86/CPU: CPU features have changed after loading microcode, but might not take effect.\n");
-	pr_warn("x86/CPU: Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
-}
-#endif
-
 /*
  * Invoked from core CPU hotplug code after hotplug operations
  */
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index c4cd7328177b..0051ebf7c53e 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -432,6 +432,37 @@ static int __reload_late(void *info)
 	return ret;
 }
 
+/*
+ * The microcode loader calls this upon late microcode load to recheck features,
+ * only when microcode has been updated. Caller holds microcode_mutex and CPU
+ * hotplug lock.
+ */
+static void microcode_check(void)
+{
+	struct cpuinfo_x86 info;
+
+	perf_check_microcode();
+
+	/* Reload CPUID max function as it might've changed. */
+	info.cpuid_level = cpuid_eax(0);
+
+	/*
+	 * Copy all capability leafs to pick up the synthetic ones so that
+	 * memcmp() below doesn't fail on that. The ones coming from CPUID will
+	 * get overwritten in get_cpu_cap().
+	 */
+	memcpy(&info.x86_capability, &boot_cpu_data.x86_capability, sizeof(info.x86_capability));
+
+	get_cpu_cap(&info);
+
+	if (!memcmp(&info.x86_capability, &boot_cpu_data.x86_capability,
+		    sizeof(info.x86_capability)))
+		return;
+
+	pr_warn("x86/CPU: CPU features have changed after loading microcode, but might not take effect.\n");
+	pr_warn("x86/CPU: Please consider either early loading through initrd/built-in or a potential BIOS update.\n");
+}
+
 /*
  * Reload microcode late on all CPUs. Wait for a sec until they
  * all gather together.
-- 
2.34.1