[PATCH v7 18/18] drm/virtio: add fence sanity check
From: Gerd Hoffmann <kraxel@redhat.com>
Date: 2019-08-02 13:12:25
Subsystem:
drm drivers, drm drivers and misc gpu patches, the rest, virtio gpu driver · Maintainers:
David Airlie, Simona Vetter, Maarten Lankhorst, Maxime Ripard, Thomas Zimmermann, Linus Torvalds, Gerd Hoffmann, Dmitry Osipenko
Make sure we don't leak half-initialized fences outside the driver. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> --- drivers/gpu/drm/virtio/virtgpu_fence.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/gpu/drm/virtio/virtgpu_fence.c b/drivers/gpu/drm/virtio/virtgpu_fence.c
index a0514f5bd006..a4b9881ca1d3 100644
--- a/drivers/gpu/drm/virtio/virtgpu_fence.c
+++ b/drivers/gpu/drm/virtio/virtgpu_fence.c@@ -41,6 +41,10 @@ bool virtio_fence_signaled(struct dma_fence *f) { struct virtio_gpu_fence *fence = to_virtio_fence(f); + if (WARN_ON_ONCE(fence->f.seqno == 0)) + /* leaked fence outside driver before completing + * initialization with virtio_gpu_fence_emit */ + return false; if (atomic64_read(&fence->drv->last_seq) >= fence->f.seqno) return true; return false;
--
2.18.1