Patch "drm/etnaviv: (re-)protect fence allocation with GPU mutex" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    drm/etnaviv: (re-)protect fence allocation with GPU mutex

to the 4.9-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:
     drm-etnaviv-re-protect-fence-allocation-with-gpu-mutex.patch
and it can be found in the queue-4.9 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 f3cd1b064f1179d9e6188c6d67297a2360880e10 Mon Sep 17 00:00:00 2001
From: Lucas Stach <l.stach@pengutronix.de>
Date: Wed, 22 Mar 2017 12:07:23 +0100
Subject: drm/etnaviv: (re-)protect fence allocation with GPU mutex

From: Lucas Stach <l.stach@pengutronix.de>

commit f3cd1b064f1179d9e6188c6d67297a2360880e10 upstream.

The fence allocation needs to be protected by the GPU mutex, otherwise
the fence seqnos of concurrent submits might not match the insertion order
of the jobs in the kernel ring. This breaks the assumption that jobs
complete with monotonically increasing fence seqnos.

Fixes: d9853490176c (drm/etnaviv: take GPU lock later in the submit process)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/etnaviv/etnaviv_gpu.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c
@@ -1299,6 +1299,8 @@ int etnaviv_gpu_submit(struct etnaviv_gp
 		goto out_pm_put;
 	}
 
+	mutex_lock(&gpu->lock);
+
 	fence = etnaviv_gpu_fence_alloc(gpu);
 	if (!fence) {
 		event_free(gpu, event);
@@ -1306,8 +1308,6 @@ int etnaviv_gpu_submit(struct etnaviv_gp
 		goto out_pm_put;
 	}
 
-	mutex_lock(&gpu->lock);
-
 	gpu->event[event].fence = fence;
 	submit->fence = fence->seqno;
 	gpu->active_fence = submit->fence;


Patches currently in stable-queue which might be from l.stach@pengutronix.de are

queue-4.9/drm-etnaviv-re-protect-fence-allocation-with-gpu-mutex.patch