[3.16.y-ckt stable] Patch "sb_edac: avoid INTERNAL ERROR message in EDAC with unspecified channel" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    sb_edac: avoid INTERNAL ERROR message in EDAC with unspecified channel

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.16.y-queue

This patch is scheduled to be released in version 3.16.7-ckt10.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From a8b50b45e7c697c94cb6050e9f2b83760aa98c80 Mon Sep 17 00:00:00 2001
From: Seth Jennings <sjenning at redhat.com>
Date: Fri, 5 Sep 2014 14:28:47 -0500
Subject: sb_edac: avoid INTERNAL ERROR message in EDAC with unspecified
 channel

commit 351fc4a99d49fde63fe5ab7412beb35c40d27269 upstream.

Intel IA32 SDM Table 15-14 defines channel 0xf as 'not specified', but
EDAC doesn't know about this and returns and INTERNAL ERROR when the
channel is greater than NUM_CHANNELS:

kernel: [ 1538.886456] CPU 0: Machine Check Exception: 0 Bank 1: 940000000000009f
kernel: [ 1538.886669] TSC 2bc68b22e7e812 ADDR 46dae7000 MISC 0 PROCESSOR 0:306e4 TIME 1390414572 SOCKET 0 APIC 0
kernel: [ 1538.971948] EDAC MC1: INTERNAL ERROR: channel value is out of range (15 >= 4)
kernel: [ 1538.972203] EDAC MC1: 0 CE memory read error on unknown memory (slot:0 page:0x46dae7 offset:0x0 grain:0 syndrome:0x0 -  area:DRAM err_code:0000:009f socket:1 channel_mask:1 rank:0)

This commit changes sb_edac to forward a channel of -1 to EDAC if the
channel is not specified.  edac_mc_handle_error() sets the channel to -1
internally after the error message anyway, so this commit should have no
effect other than avoiding the INTERNAL ERROR message when the channel
is not specified.

Signed-off-by: Seth Jennings <sjenning at redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab at osg.samsung.com>
Cc: Vinson Lee <vlee at twopensource.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/edac/sb_edac.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c
index aa174f3a9e45..ff75f8904735 100644
--- a/drivers/edac/sb_edac.c
+++ b/drivers/edac/sb_edac.c
@@ -285,8 +285,9 @@ static const u32 correrrthrsld[] = {
  * sbridge structs
  */

-#define NUM_CHANNELS	4
-#define MAX_DIMMS	3		/* Max DIMMS per channel */
+#define NUM_CHANNELS		4
+#define MAX_DIMMS		3	/* Max DIMMS per channel */
+#define CHANNEL_UNSPECIFIED	0xf	/* Intel IA32 SDM 15-14 */

 enum type {
 	SANDY_BRIDGE,
@@ -1752,6 +1753,9 @@ static void sbridge_mce_output_error(struct mem_ctl_info *mci,

 	/* FIXME: need support for channel mask */

+	if (channel == CHANNEL_UNSPECIFIED)
+		channel = -1;
+
 	/* Call the helper to output message */
 	edac_mc_handle_error(tp_event, mci, core_err_cnt,
 			     m->addr >> PAGE_SHIFT, m->addr & ~PAGE_MASK, 0,