Patch "dma-buf: fix reservation_object_wait_timeout_rcu once more v2" has been added to the 4.15-stable tree

Patch "dma-buf: fix reservation_object_wait_timeout_rcu once more v2" has been added to the 4.15-stable tree

[gregkh]

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

    dma-buf: fix reservation_object_wait_timeout_rcu once more v2

to the 4.15-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:
     dma-buf-fix-reservation_object_wait_timeout_rcu-once-more-v2.patch
and it can be found in the queue-4.15 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 5bffee867df7494ecd32c1e6ec4e8fc934c521b7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christian=20K=C3=B6nig?= <ckoenig.leichtzumerken@gmail.com>
Date: Mon, 22 Jan 2018 21:00:03 +0100
Subject: dma-buf: fix reservation_object_wait_timeout_rcu once more v2
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

From: Christian König <ckoenig.leichtzumerken@gmail.com>

commit 5bffee867df7494ecd32c1e6ec4e8fc934c521b7 upstream.

We need to set shared_count even if we already have a fence to wait for.

v2: init i to -1 as well

Signed-off-by: Christian König <christian.koenig@amd.com>
Cc: stable@vger.kernel.org
Tested-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180122200003.6665-1-christian.koenig@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/dma-buf/reservation.c |    8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

--- a/drivers/dma-buf/reservation.c
+++ b/drivers/dma-buf/reservation.c
@@ -455,13 +455,15 @@ long reservation_object_wait_timeout_rcu
 					 unsigned long timeout)
 {
 	struct dma_fence *fence;
-	unsigned seq, shared_count, i = 0;
+	unsigned seq, shared_count;
 	long ret = timeout ? timeout : 1;
+	int i;
 
 retry:
 	shared_count = 0;
 	seq = read_seqcount_begin(&obj->seq);
 	rcu_read_lock();
+	i = -1;
 
 	fence = rcu_dereference(obj->fence_excl);
 	if (fence && !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) {
@@ -477,14 +479,14 @@ retry:
 		fence = NULL;
 	}
 
-	if (!fence && wait_all) {
+	if (wait_all) {
 		struct reservation_object_list *fobj =
 						rcu_dereference(obj->fence);
 
 		if (fobj)
 			shared_count = fobj->shared_count;
 
-		for (i = 0; i < shared_count; ++i) {
+		for (i = 0; !fence && i < shared_count; ++i) {
 			struct dma_fence *lfence = rcu_dereference(fobj->shared[i]);
 
 			if (test_bit(DMA_FENCE_FLAG_SIGNALED_BIT,


Patches currently in stable-queue which might be from ckoenig.leichtzumerken@gmail.com are

queue-4.15/dma-buf-fix-reservation_object_wait_timeout_rcu-once-more-v2.patch
queue-4.15/swiotlb-suppress-warning-when-__gfp_nowarn-is-set.patch