Patch "IB/hfi1: Reset QSFP on every run through channel tuning" has been added to the 4.7-stable tree

Patch "IB/hfi1: Reset QSFP on every run through channel tuning" has been added to the 4.7-stable tree

[gregkh]

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

    IB/hfi1: Reset QSFP on every run through channel tuning

to the 4.7-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:
     ib-hfi1-reset-qsfp-on-every-run-through-channel-tuning.patch
and it can be found in the queue-4.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From b5e710195492f682d93097cddac13e594d39a946 Mon Sep 17 00:00:00 2001
From: Easwar Hariharan <easwar.hariharan@intel.com>
Date: Mon, 25 Jul 2016 13:40:03 -0700
Subject: IB/hfi1: Reset QSFP on every run through channel tuning

From: Easwar Hariharan <easwar.hariharan@intel.com>

commit b5e710195492f682d93097cddac13e594d39a946 upstream.

Active QSFP cables were reset only every alternate iteration of the
channel tuning algorithm instead of every iteration due to incorrect
reset of the flag that controlled QSFP reset, resulting in using stale
QSFP status in the channel tuning algorithm.

Fixes: 8ebd4cf1852a ("Add active and optical cable support")
Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Easwar Hariharan <easwar.hariharan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/infiniband/hw/hfi1/platform.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/infiniband/hw/hfi1/platform.c
+++ b/drivers/infiniband/hw/hfi1/platform.c
@@ -638,9 +638,13 @@ static int tune_active_qsfp(struct hfi1_
 	if (ret)
 		return ret;
 
+	/*
+	 * We'll change the QSFP memory contents from here on out, thus we set a
+	 * flag here to remind ourselves to reset the QSFP module. This prevents
+	 * reuse of stale settings established in our previous pass through.
+	 */
 	if (ppd->qsfp_info.reset_needed) {
 		reset_qsfp(ppd);
-		ppd->qsfp_info.reset_needed = 0;
 		refresh_qsfp_cache(ppd, &ppd->qsfp_info);
 	} else {
 		ppd->qsfp_info.reset_needed = 1;


Patches currently in stable-queue which might be from easwar.hariharan@intel.com are

queue-4.7/ib-hfi1-reset-qsfp-on-every-run-through-channel-tuning.patch