Re: [PATCH] drm: omapdrm: Fix implicit dma_buf fencing

From: Tomi Valkeinen
Date: Thu Jan 06 2022 - 08:43:14 EST


Hi,

On 05/01/2022 17:36, Ivaylo Dimitrov wrote:
Currently omapdrm driver does not initialize dma_buf_export_info resv
member, which leads to a new dma_resv being allocated and attached to
the exported dma_buf. This leads to the issue that fences created on
dma_buf objects imported by other drivers are ignored by omapdrm, as only
fences in gem object resv are waited on. This leads to various issues like
displaying incomplete frames.

Fix that by initializing dma_buf resv to the resv of the gem object being
exported.

Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@xxxxxxxxx>
---
drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c b/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
index f1f93cabb61e..a111e5c91925 100644
--- a/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c
@@ -88,6 +88,7 @@ struct dma_buf *omap_gem_prime_export(struct drm_gem_object *obj, int flags)
exp_info.size = omap_gem_mmap_size(obj);
exp_info.flags = flags;
exp_info.priv = obj;
+ exp_info.resv = obj->resv;
return drm_gem_dmabuf_export(obj->dev, &exp_info);
}

Thanks! Pushed to drm-misc-next.

Tomi