linux-kernel - [PATCH 6/7] EDAC, mce_amd: Detect SMCA using X86_FEATURE

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Message-Id: <1462971509-3856-7-git-send-email-bp@alien8.de>
Date:	Wed, 11 May 2016 14:58:28 +0200
From:	Borislav Petkov <bp@...en8.de>
To:	Ingo Molnar <mingo@...nel.org>
Cc:	LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH 6/7] EDAC, mce_amd: Detect SMCA using X86_FEATURE_SMCA

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

Use X86_FEATURE_SMCA when detecting if SMCA is available instead of
directly using CPUID 0x80000007_EBX.

Signed-off-by: Yazen Ghannam <Yazen.Ghannam@....com>
Cc: <x86@...nel.org>
Cc: Tony Luck <tony.luck@...el.com>
Cc: linux-edac <linux-edac@...r.kernel.org>
Link: http://lkml.kernel.org/r/1462914639-29513-5-git-send-email-Yazen.Ghannam@amd.com
Signed-off-by: Borislav Petkov <bp@...e.de>
---
 drivers/edac/mce_amd.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c
index 49768c08ac07..9b6800a79c7f 100644
--- a/drivers/edac/mce_amd.c
+++ b/drivers/edac/mce_amd.c
@@ -1052,7 +1052,6 @@ int amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
 	struct mce *m = (struct mce *)data;
 	struct cpuinfo_x86 *c = &cpu_data(m->extcpu);
 	int ecc;
-	u32 ebx = cpuid_ebx(0x80000007);
 
 	if (amd_filter_mce(m))
 		return NOTIFY_STOP;
@@ -1075,7 +1074,7 @@ int amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
 			((m->status & MCI_STATUS_DEFERRED) ? "Deferred" : "-"),
 			((m->status & MCI_STATUS_POISON)   ? "Poison"   : "-"));
 
-	if (!!(ebx & BIT(3))) {
+	if (boot_cpu_has(X86_FEATURE_SMCA)) {
 		u32 low, high;
 		u32 addr = MSR_AMD64_SMCA_MCx_CONFIG(m->bank);
 
@@ -1094,7 +1093,7 @@ int amd_decode_mce(struct notifier_block *nb, unsigned long val, void *data)
 	if (m->status & MCI_STATUS_ADDRV)
 		pr_emerg(HW_ERR "MC%d Error Address: 0x%016llx\n", m->bank, m->addr);
 
-	if (!!(ebx & BIT(3))) {
+	if (boot_cpu_has(X86_FEATURE_SMCA)) {
 		decode_smca_errors(m);
 		goto err_code;
 	}
@@ -1149,7 +1148,6 @@ static struct notifier_block amd_mce_dec_nb = {
 static int __init mce_amd_init(void)
 {
 	struct cpuinfo_x86 *c = &boot_cpu_data;
-	u32 ebx;
 
 	if (c->x86_vendor != X86_VENDOR_AMD)
 		return -ENODEV;
@@ -1205,9 +1203,8 @@ static int __init mce_amd_init(void)
 		break;
 
 	case 0x17:
-		ebx = cpuid_ebx(0x80000007);
 		xec_mask = 0x3f;
-		if (!(ebx & BIT(3))) {
+		if (!boot_cpu_has(X86_FEATURE_SMCA)) {
 			printk(KERN_WARNING "Decoding supported only on Scalable MCA processors.\n");
 			goto err_out;
 		}
-- 
2.7.3