Patch "EDAC, sb_edac: Fix TAD presence check for sbridge_mci_bind_devs()" has been added to the 4.2-stable tree

This is a note to let you know that I've just added the patch titled

EDAC, sb_edac: Fix TAD presence check for sbridge_mci_bind_devs()

to the 4.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
edac-sb_edac-fix-tad-presence-check-for-sbridge_mci_bind_devs.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Seth Jennings <[email protected]>
Date: Wed, 5 Aug 2015 13:16:01 -0500
Subject: EDAC, sb_edac: Fix TAD presence check for sbridge_mci_bind_devs()

From: Seth Jennings <[email protected]>

commit 2900ea609616c2651dec65312beeb2a6e536bc50 upstream.

In commit

7d375bffa524 ("sb_edac: Fix support for systems with two home agents per socket")

NUM_CHANNELS was changed to 8 and the channel space was renumerated to handle EN, EP, and EX configurations.

The *_mci_bind_devs() functions - except for sbridge_mci_bind_devs() - got a new device presence check in the form of saw_chan_mask. However, sbridge_mci_bind_devs() still uses the NUM_CHANNELS for loop.

With the increase in NUM_CHANNELS, this loop fails at index 4 since SB only has 4 TADs. This results in the following error on SB machines:

EDAC sbridge: Some needed devices are missing
EDAC sbridge: Couldn't find mci handler
EDAC sbridge: Couldn't find mci handle

This patch adapts the saw_chan_mask logic for sbridge_mci_bind_devs() as well.

After this patch:

EDAC MC0: Giving out device to module sbridge_edac.c controller Sandy Bridge Socket#0: DEV 0000:3f:0e.0 (POLLED) EDAC MC1: Giving out device to module sbridge_edac.c controller Sandy Bridge Socket#1: DEV 0000:7f:0e.0 (POLLED)

---
 drivers/edac/sb_edac.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

@@ -1648,6 +1648,7 @@ static int sbridge_mci_bind_devs(struct
 {
 	struct sbridge_pvt *pvt = mci->pvt_info;
 	struct pci_dev *pdev;
+	u8 saw_chan_mask = 0;
 	int i;
 
 	for (i = 0; i < sbridge_dev->n_devs; i++) {

@@ -1681,6 +1682,7 @@ static int sbridge_mci_bind_devs(struct
 		{
 			int id = pdev->device - PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD0;
 			pvt->pci_tad[id] = pdev;
+			saw_chan_mask |= 1 << id;
 		}
 			break;
 		case PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_DDRIO:

@@ -1701,10 +1703,8 @@ static int sbridge_mci_bind_devs(struct
 	    !pvt-> pci_tad || !pvt->pci_ras  || !pvt->pci_ta)
 		goto enodev;
 
-	for (i = 0; i < NUM_CHANNELS; i++) {
-		if (!pvt->pci_tad[i])
-			goto enodev;
-	}
+	if (saw_chan_mask != 0x0f)
+		goto enodev;
 	return 0;
 
 enodev:

Patches currently in stable-queue which might be from [email protected] are

queue-4.2/edac-sb_edac-fix-tad-presence-check-for-sbridge_mci_bind_devs.patch