linux-kernel - [PATCH 4/3] x86/microcode: Remove unnecessary perf callback default-disable late loading

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Date:   Wed, 25 May 2022 15:55:54 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     Peter Zijlstra <peterz@...radead.org>
Cc:     X86 ML <x86@...nel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH 4/3] x86/microcode: Remove unnecessary perf callback
 default-disable late loading

From: Borislav Petkov <bp@...e.de>

c93dc84cbe32 ("perf/x86: Add a microcode revision check for SNB-PEBS")
checks whether the microcode revision has fixed PEBS issues.

This can happen either:

1. At PEBS init time, where the early microcode has been loaded already

2. During late loading, in the microcode_check() callback.

So remove the unnecessary call in the microcode loader init routine.

Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/kernel/cpu/microcode/core.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index 801b44ac3851..ad57e0e4d674 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -756,10 +756,7 @@ static int __init microcode_init(void)
 
 	cpus_read_lock();
 	mutex_lock(&microcode_mutex);
-
 	error = subsys_interface_register(&mc_cpu_interface);
-	if (!error)
-		perf_check_microcode();
 	mutex_unlock(&microcode_mutex);
 	cpus_read_unlock();
 
-- 
2.35.1


-- 
Regards/Gruss,
    Boris.

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