linux-kernel - [PATCH v8 3/5] x86/cpuid: Make clearcpuid an early param

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Message-Id: <20171005215256.25659-4-andi@firstfloor.org>
Date:   Thu,  5 Oct 2017 14:52:54 -0700
From:   Andi Kleen <andi@...stfloor.org>
To:     x86@...nel.org
Cc:     hpa@...or.com, linux-kernel@...r.kernel.org,
        Andi Kleen <ak@...ux.intel.com>
Subject: [PATCH v8 3/5] x86/cpuid: Make clearcpuid an early param

From: Andi Kleen <ak@...ux.intel.com>

Make clearcpuid= an early param, to make sure it is parsed
before the XSAVE initialization. This allows to modify
XSAVE state by clearing specific CPUID bits.

Reviewed-by: Thomas Gleixner <tglx@...utronix.de>
Signed-off-by: Andi Kleen <ak@...ux.intel.com>
---
 arch/x86/kernel/cpu/common.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index fd47692e5ce9..ff51c61d2df0 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1310,7 +1310,7 @@ static __init int setup_disablecpuid(char *arg)
 
 	return 1;
 }
-__setup("clearcpuid=", setup_disablecpuid);
+early_param("clearcpuid", setup_disablecpuid);
 
 #ifdef CONFIG_X86_64
 DEFINE_PER_CPU_FIRST(union irq_stack_union,
-- 
2.13.6