linux-kernel - [PATCH 14/15] x86/MCE/AMD, EDAC: Handle reserved bank 4 on Fam17h properly

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Date:   Mon, 12 Sep 2016 09:59:40 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     X86 ML <x86@...nel.org>
Cc:     LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH 14/15] x86/MCE/AMD, EDAC: Handle reserved bank 4 on Fam17h properly

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

Bank 4 is reserved on family 0x17 and shouldn't generate any MCE
records. However, broken hardware and software is not something unheard
of so warn about bank 4 errors. They shouldn't be coming from bank 4
naturally but users can still use mce_amd_inj to simulate errors from it
for testing purposed.

Also, avoid special handling in the injector mce_amd_inj like it is
being done on the older families.

Signed-off-by: Yazen Ghannam <Yazen.Ghannam@....com>
Reviewed-by: Aravind Gopalakrishnan  <aravindksg.lkml@...il.com>
Cc: linux-edac <linux-edac@...r.kernel.org>
Cc: x86-ml <x86@...nel.org>
Link: http://lkml.kernel.org/r/1473384591-5323-1-git-send-email-Yazen.Ghannam@amd.com
Link: http://lkml.kernel.org/r/1473384591-5323-2-git-send-email-Yazen.Ghannam@amd.com
[ Rewrite commit message and merge into one patch. Use boot_cpu_data. ]
Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/ras/mce_amd_inj.c | 4 +++-
 drivers/edac/mce_amd.c     | 3 +++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/ras/mce_amd_inj.c b/arch/x86/ras/mce_amd_inj.c
index ff8eb1a9ce6d..f4b442cc8a3e 100644
--- a/arch/x86/ras/mce_amd_inj.c
+++ b/arch/x86/ras/mce_amd_inj.c
@@ -308,7 +308,9 @@ static void do_inject(void)
 	 * only on the node base core. Refer to D18F3x44[NbMcaToMstCpuEn] for
 	 * Fam10h and later BKDGs.
 	 */
-	if (static_cpu_has(X86_FEATURE_AMD_DCM) && b == 4) {
+	if (static_cpu_has(X86_FEATURE_AMD_DCM) &&
+	    b == 4 &&
+	    boot_cpu_data.x86 < 0x17) {
 		toggle_nb_mca_mst_cpu(amd_get_nb_id(cpu));
 		cpu = get_nbc_for_node(amd_get_nb_id(cpu));
 	}
diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c
index e8855a4f92d9..daaac2c79ca7 100644
--- a/drivers/edac/mce_amd.c
+++ b/drivers/edac/mce_amd.c
@@ -859,6 +859,9 @@ static void decode_smca_errors(struct mce *m)
 	if (m->bank >= ARRAY_SIZE(smca_banks))
 		return;
 
+	if (boot_cpu_data.x86 >= 0x17 && m->bank == 4)
+		pr_emerg(HW_ERR "Bank 4 is reserved on Fam17h.\n");
+
 	type = smca_banks[m->bank].type;
 	if (!type)
 		return;
-- 
2.10.0