Patch "drm/ttm: fix ttm_bo_cleanup_refs_or_queue once more" has been added to the 4.14-stable tree

[<gregkh@linuxfoundation.org>]

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

    drm/ttm: fix ttm_bo_cleanup_refs_or_queue once more

to the 4.14-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:
     drm-ttm-fix-ttm_bo_cleanup_refs_or_queue-once-more.patch
and it can be found in the queue-4.14 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 378e2d5b504fe0231c557751e58b80fcf717cc20 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=B6nig?= <christian.koenig@amd.com>
Date: Mon, 4 Sep 2017 20:58:45 +0200
Subject: drm/ttm: fix ttm_bo_cleanup_refs_or_queue once more
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Christian König <christian.koenig@amd.com>

commit 378e2d5b504fe0231c557751e58b80fcf717cc20 upstream.

With shared reservation objects __ttm_bo_reserve() can easily fail even on
destroyed BOs. This prevents correct handling when we need to individualize
the reservation object.

Fix this by individualizing the object before even trying to reserve it.

Signed-off-by: Christian König <christian.koenig@amd.com>
Acked-by: Chunming Zhou <david1.zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/ttm/ttm_bo.c |   32 +++++++++++++++++---------------
 1 file changed, 17 insertions(+), 15 deletions(-)

--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -440,28 +440,29 @@ static void ttm_bo_cleanup_refs_or_queue
 	struct ttm_bo_global *glob = bo->glob;
 	int ret;
 
+	ret = ttm_bo_individualize_resv(bo);
+	if (ret) {
+		/* Last resort, if we fail to allocate memory for the
+		 * fences block for the BO to become idle
+		 */
+		reservation_object_wait_timeout_rcu(bo->resv, true, false,
+						    30 * HZ);
+		spin_lock(&glob->lru_lock);
+		goto error;
+	}
+
 	spin_lock(&glob->lru_lock);
 	ret = __ttm_bo_reserve(bo, false, true, NULL);
-
 	if (!ret) {
-		if (!ttm_bo_wait(bo, false, true)) {
+		if (reservation_object_test_signaled_rcu(&bo->ttm_resv, true)) {
 			ttm_bo_del_from_lru(bo);
 			spin_unlock(&glob->lru_lock);
+			if (bo->resv != &bo->ttm_resv)
+				reservation_object_unlock(&bo->ttm_resv);
 			ttm_bo_cleanup_memtype_use(bo);
-
 			return;
 		}
 
-		ret = ttm_bo_individualize_resv(bo);
-		if (ret) {
-			/* Last resort, if we fail to allocate memory for the
-			 * fences block for the BO to become idle and free it.
-			 */
-			spin_unlock(&glob->lru_lock);
-			ttm_bo_wait(bo, true, true);
-			ttm_bo_cleanup_memtype_use(bo);
-			return;
-		}
 		ttm_bo_flush_all_fences(bo);
 
 		/*
@@ -474,11 +475,12 @@ static void ttm_bo_cleanup_refs_or_queue
 			ttm_bo_add_to_lru(bo);
 		}
 
-		if (bo->resv != &bo->ttm_resv)
-			reservation_object_unlock(&bo->ttm_resv);
 		__ttm_bo_unreserve(bo);
 	}
+	if (bo->resv != &bo->ttm_resv)
+		reservation_object_unlock(&bo->ttm_resv);
 
+error:
 	kref_get(&bo->list_kref);
 	list_add_tail(&bo->ddestroy, &bdev->ddestroy);
 	spin_unlock(&glob->lru_lock);


Patches currently in stable-queue which might be from christian.koenig@amd.com are

queue-4.14/drm-ttm-fix-ttm_bo_cleanup_refs_or_queue-once-more.patch
queue-4.14/drm-amdgpu-potential-uninitialized-variable-in-amdgpu_vce_ring_parse_cs.patch
queue-4.14/drm-amdgpu-properly-allocate-vm-invalidate-eng-v2.patch
queue-4.14/drm-amdgpu-potential-uninitialized-variable-in-amdgpu_vm_update_directories.patch
queue-4.14/drm-amdgpu-fix-error-handling-in-amdgpu_bo_do_create.patch
queue-4.14/dma-buf-make-reservation_object_copy_fences-rcu-save.patch