linux-kernel - [PATCH 5/7] x86/mce: Update AMD mcheck init to use cpu

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Date:	Wed, 11 May 2016 14:58:27 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Ingo Molnar <mingo@...nel.org>
Cc:	LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH 5/7] x86/mce: Update AMD mcheck init to use cpu_has() facilities

From: Yazen Ghannam <Yazen.Ghannam@....com>

Use cpu_has() facilities to find available RAS features rather than
directly reading CPUID 0x80000007_EBX.

Signed-off-by: Yazen Ghannam <Yazen.Ghannam@....com>
Cc: Tony Luck <tony.luck@...el.com>
Cc: linux-edac <linux-edac@...r.kernel.org>
Cc: x86-ml <x86@...nel.org>
Link: http://lkml.kernel.org/r/1462914639-29513-4-git-send-email-Yazen.Ghannam@amd.com
[ Use the struct cpuinfo_x86 ptr instead. ]
Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/kernel/cpu/mcheck/mce.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index aeda44684758..92e5e37d97bf 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1683,11 +1683,9 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
 		break;
 
 	case X86_VENDOR_AMD: {
-		u32 ebx = cpuid_ebx(0x80000007);
-
-		mce_flags.overflow_recov = !!(ebx & BIT(0));
-		mce_flags.succor	 = !!(ebx & BIT(1));
-		mce_flags.smca		 = !!(ebx & BIT(3));
+		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);
 
 		/*
 		 * Install proper ops for Scalable MCA enabled processors
-- 
2.7.3