linux-kernel - [PATCH v4 3/5] x86/cpuid: Make clearcpuid an early param

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Message-Id: <20170725004353.5280-4-andi@firstfloor.org>
Date:   Mon, 24 Jul 2017 17:43:51 -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 v4 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.

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 60b7aa6330ed..600e0cf714b9 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1285,7 +1285,7 @@ static __init int setup_disablecpuid(char *arg)
 
 	return 1;
 }
-__setup("clearcpuid=", setup_disablecpuid);
+early_param("clearcpuid", setup_disablecpuid);
 
 #ifdef CONFIG_X86_64
 struct desc_ptr idt_descr __ro_after_init = {
-- 
2.9.4