Patch "[PATCH] drm/radeon: hold reference to fences in radeon_sa_bo_new" has been added to the 3.14-stable tree

Patch "[PATCH] drm/radeon: hold reference to fences in radeon_sa_bo_new" has been added to the 3.14-stable tree

[gregkh]

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

    [PATCH] drm/radeon: hold reference to fences in radeon_sa_bo_new

to the 3.14-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:
     0001-drm-radeon-hold-reference-to-fences-in-radeon_sa_bo_.patch
and it can be found in the queue-3.14 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 ad94965f69c2681832f64473d28c23ae71b6e52f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nicolai=20H=C3=A4hnle?= <nicolai.haehnle@amd.com>
Date: Tue, 15 Mar 2016 12:56:45 -0500
Subject: [PATCH] drm/radeon: hold reference to fences in radeon_sa_bo_new
 (3.17 and older)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Nicolai Hähnle <nicolai.haehnle@amd.com>

[Backport of upstream commit f6ff4f67cdf8455d0a4226eeeaf5af17c37d05eb, with
 an additional NULL pointer guard that is required for kernels 3.17 and older.

 To be precise, any kernel that does *not* have commit 954605ca3 "drm/radeon:
 use common fence implementation for fences, v4" requires this additional
 NULL pointer guard.]

An arbitrary amount of time can pass between spin_unlock and
radeon_fence_wait_any, so we need to ensure that nobody frees the
fences from under us.

Based on the analogous fix for amdgpu.

Signed-off-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com> (v1 + fix)
Tested-by: Lutz Euler <lutz.euler@freenet.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/gpu/drm/radeon/radeon_sa.c |    7 +++++++
 1 file changed, 7 insertions(+)

--- a/drivers/gpu/drm/radeon/radeon_sa.c
+++ b/drivers/gpu/drm/radeon/radeon_sa.c
@@ -349,8 +349,15 @@ int radeon_sa_bo_new(struct radeon_devic
 			/* see if we can skip over some allocations */
 		} while (radeon_sa_bo_next_hole(sa_manager, fences, tries));
 
+		for (i = 0; i < RADEON_NUM_RINGS; ++i) {
+			if (fences[i])
+				radeon_fence_ref(fences[i]);
+		}
+
 		spin_unlock(&sa_manager->wq.lock);
 		r = radeon_fence_wait_any(rdev, fences, false);
+		for (i = 0; i < RADEON_NUM_RINGS; ++i)
+			radeon_fence_unref(&fences[i]);
 		spin_lock(&sa_manager->wq.lock);
 		/* if we have nothing to wait for block */
 		if (r == -ENOENT && block) {


Patches currently in stable-queue which might be from nicolai.haehnle@amd.com are

queue-3.14/0001-drm-radeon-hold-reference-to-fences-in-radeon_sa_bo_.patch
queue-3.14/revert-bad-backport-of-drm-radeon-hold-reference-to-fences-in-radeon_sa_bo_new.patch