linux-kernel - [PATCH 7/7] x86/microcode: Remove microcode_nmi_handler

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Message-ID: <20260125014224.249901-8-chang.seok.bae@intel.com>
Date: Sun, 25 Jan 2026 01:42:22 +0000
From: "Chang S. Bae" <chang.seok.bae@...el.com>
To: linux-kernel@...r.kernel.org
Cc: x86@...nel.org,
	tglx@...utronix.de,
	mingo@...hat.com,
	bp@...en8.de,
	dave.hansen@...ux.intel.com,
	peterz@...radead.org,
	david.kaplan@....com,
	chang.seok.bae@...el.com
Subject: [PATCH 7/7] x86/microcode: Remove microcode_nmi_handler_enable

Remove it, as there is no more user.

Signed-off-by: Chang S. Bae <chang.seok.bae@...el.com>
---
 arch/x86/include/asm/microcode.h     | 7 -------
 arch/x86/kernel/cpu/microcode/core.c | 8 ++------
 2 files changed, 2 insertions(+), 13 deletions(-)

diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index a4e4ea8acf99..b7e89fc45500 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -79,15 +79,8 @@ static inline u32 intel_get_microcode_revision(void)
 
 #ifdef CONFIG_MICROCODE_LATE_LOADING
 void microcode_offline_nmi_handler(void);
-
-DECLARE_STATIC_KEY_FALSE(microcode_nmi_handler_enable);
-static __always_inline bool microcode_nmi_handler_enabled(void)
-{
-	return static_branch_unlikely(&microcode_nmi_handler_enable);
-}
 #else
 static __always_inline void microcode_offline_nmi_handler(void) { }
-static __always_inline bool microcode_nmi_handler_enabled(void) { return false; }
 #endif
 
 #endif /* _ASM_X86_MICROCODE_H */
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index 0facadea39d6..35b1b5d88893 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -316,7 +316,6 @@ struct microcode_ctrl {
 	bool			nmi_enabled;
 };
 
-DEFINE_STATIC_KEY_FALSE(microcode_nmi_handler_enable);
 static DEFINE_PER_CPU(struct microcode_ctrl, ucode_ctrl);
 static atomic_t late_cpus_in, offline_in_nmi;
 static unsigned int loops_per_usec;
@@ -593,13 +592,10 @@ static int load_late_stop_cpus(bool is_safe)
 	 */
 	store_cpu_caps(&prev_info);
 
-	if (microcode_ops->use_nmi) {
-		static_branch_enable_cpuslocked(&microcode_nmi_handler_enable);
+	if (microcode_ops->use_nmi)
 		stop_machine_cpuslocked_nmi(microcode_nmi_handler, NULL, cpu_online_mask);
-		static_branch_disable_cpuslocked(&microcode_nmi_handler_enable);
-	} else {
+	else
 		stop_machine_cpuslocked(microcode_update_handler, NULL, cpu_online_mask);
-	}
 
 	/* Analyze the results */
 	for_each_cpu_and(cpu, cpu_present_mask, &cpus_booted_once_mask) {
-- 
2.51.0