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

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 <[email protected]> know about it.

From: =?UTF-8?q?Nicolai=20H=C3=A4hnle?= <[email protected]>
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)
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From: Nicolai Hähnle <[email protected]>

[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.

---
 drivers/gpu/drm/radeon/radeon_sa.c |    7 +++++++
 1 file changed, 7 insertions(+)

@@ -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 [email protected] 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