linux-kernel - [PATCH v5 06/20] x86/mce: Remove __mcheck_cpu_init

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Message-ID: <20250825-wip-mca-updates-v5-6-865768a2eef8@amd.com>
Date: Mon, 25 Aug 2025 17:33:03 +0000
From: Yazen Ghannam <yazen.ghannam@....com>
To: <x86@...nel.org>, Tony Luck <tony.luck@...el.com>, "Rafael J. Wysocki"
	<rafael@...nel.org>
CC: <linux-kernel@...r.kernel.org>, <linux-edac@...r.kernel.org>,
	<Smita.KoralahalliChannabasappa@....com>, Qiuxu Zhuo <qiuxu.zhuo@...el.com>,
	Nikolay Borisov <nik.borisov@...e.com>, <linux-acpi@...r.kernel.org>, "Yazen
 Ghannam" <yazen.ghannam@....com>
Subject: [PATCH v5 06/20] x86/mce: Remove __mcheck_cpu_init_early()

The __mcheck_cpu_init_early() function was introduced so that some
vendor-specific features are detected before the first MCA polling event
done in __mcheck_cpu_init_generic().

Currently, __mcheck_cpu_init_early() is only used on AMD-based systems and
additional code will be needed to support various system configurations.

However, the current and future vendor-specific code should be done during
vendor init. This keeps all the vendor code in a common location and
simplifies the generic init flow.

Move all the __mcheck_cpu_init_early() code into mce_amd_feature_init().

Reviewed-by: Qiuxu Zhuo <qiuxu.zhuo@...el.com>
Tested-by: Tony Luck <tony.luck@...el.com>
Reviewed-by: Tony Luck <tony.luck@...el.com>
Reviewed-by: Nikolay Borisov <nik.borisov@...e.com>
Signed-off-by: Yazen Ghannam <yazen.ghannam@....com>
---

Notes:
    Link:
    https://lore.kernel.org/r/20250624-wip-mca-updates-v4-10-236dd74f645f@amd.com
    
    v4->v5:
    * Add tag from Nikolay.
    * Move __mcheck_cpu_init_generic() change to new patch.
    
    v3->v4:
    * No change.
    
    v2->v3:
    * Update commit message.
    * Add tags from Qiuxu and Tony.
    
    v1->v2:
    * New in v2, but based on old patch (see link).
    * Changed cpu_has() to cpu_feature_enabled().

 arch/x86/kernel/cpu/mce/amd.c  |  4 ++++
 arch/x86/kernel/cpu/mce/core.c | 14 --------------
 2 files changed, 4 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
index 54f02bda75aa..c7632da8b460 100644
--- a/arch/x86/kernel/cpu/mce/amd.c
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -657,6 +657,10 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c)
 	u32 low = 0, high = 0, address = 0;
 	int offset = -1;
 
+	mce_flags.overflow_recov = cpu_feature_enabled(X86_FEATURE_OVERFLOW_RECOV);
+	mce_flags.succor	 = cpu_feature_enabled(X86_FEATURE_SUCCOR);
+	mce_flags.smca		 = cpu_feature_enabled(X86_FEATURE_SMCA);
+	mce_flags.amd_threshold	 = 1;
 
 	for (bank = 0; bank < this_cpu_read(mce_num_banks); ++bank) {
 		if (mce_flags.smca)
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 311876e3f3f4..0326fbb83adc 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -2034,19 +2034,6 @@ static bool __mcheck_cpu_ancient_init(struct cpuinfo_x86 *c)
 	return false;
 }
 
-/*
- * Init basic CPU features needed for early decoding of MCEs.
- */
-static void __mcheck_cpu_init_early(struct cpuinfo_x86 *c)
-{
-	if (c->x86_vendor == X86_VENDOR_AMD || c->x86_vendor == X86_VENDOR_HYGON) {
-		mce_flags.overflow_recov = !!cpu_has(c, X86_FEATURE_OVERFLOW_RECOV);
-		mce_flags.succor	 = !!cpu_has(c, X86_FEATURE_SUCCOR);
-		mce_flags.smca		 = !!cpu_has(c, X86_FEATURE_SMCA);
-		mce_flags.amd_threshold	 = 1;
-	}
-}
-
 static void mce_centaur_feature_init(struct cpuinfo_x86 *c)
 {
 	struct mca_config *cfg = &mca_cfg;
@@ -2285,7 +2272,6 @@ void mcheck_cpu_init(struct cpuinfo_x86 *c)
 
 	mca_cfg.initialized = 1;
 
-	__mcheck_cpu_init_early(c);
 	__mcheck_cpu_init_generic();
 	__mcheck_cpu_init_vendor(c);
 	__mcheck_cpu_init_prepare_banks();

-- 
2.51.0