linux-kernel - [PATCH 13/15] x86/mce/AMD: Extract the error address on SMCA systems

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Date:   Mon, 12 Sep 2016 09:59:39 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     X86 ML <x86@...nel.org>
Cc:     LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH 13/15] x86/mce/AMD: Extract the error address on SMCA systems

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

The MCA_ADDR registers on Scalable MCA systems contain the ErrorAddr
in bits [55:0] and the least significant bit of the address in bits
[61:56]. We should extract the valid ErrorAddr bits from the MCA_ADDR
register rather than saving the raw value to struct mce.

Signed-off-by: Yazen Ghannam <Yazen.Ghannam@....com>
Cc: 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/1473275643-1721-1-git-send-email-Yazen.Ghannam@amd.com
Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/kernel/cpu/mcheck/mce.c     | 10 ++++++++++
 arch/x86/kernel/cpu/mcheck/mce_amd.c | 13 ++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index ae1f47772d4f..1079391265f4 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -587,6 +587,16 @@ static void mce_read_aux(struct mce *m, int i)
 			m->addr >>= shift;
 			m->addr <<= shift;
 		}
+
+		/*
+		 * Extract [55:<lsb>] where lsb is the least significant
+		 * *valid* bit of the address bits.
+		 */
+		if (mce_flags.smca) {
+			u8 lsb = (m->addr >> 56) & 0x3f;
+
+			m->addr &= GENMASK_ULL(55, lsb);
+		}
 	}
 
 	if (mce_flags.smca) {
diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index d2f92ab5322f..9b5403462936 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -561,9 +561,20 @@ __log_error(unsigned int bank, bool deferred_err, bool threshold_err, u64 misc)
 	if (threshold_err)
 		m.misc = misc;
 
-	if (m.status & MCI_STATUS_ADDRV)
+	if (m.status & MCI_STATUS_ADDRV) {
 		rdmsrl(msr_addr, m.addr);
 
+		/*
+		 * Extract [55:<lsb>] where lsb is the least significant
+		 * *valid* bit of the address bits.
+		 */
+		if (mce_flags.smca) {
+			u8 lsb = (m.addr >> 56) & 0x3f;
+
+			m.addr &= GENMASK_ULL(55, lsb);
+		}
+	}
+
 	if (mce_flags.smca) {
 		rdmsrl(MSR_AMD64_SMCA_MCx_IPID(bank), m.ipid);
 
-- 
2.10.0