Re: [PATCH 1/5] drm/prime: fix potential race in drm_gem_map_detach

Ping? Anybody who could give me an review on those changes?

The first one is just nice to have, the rest is a nice memory usage reduction in some cases.

Christian.

Am 27.02.2018 um 12:49 schrieb Christian König:

Unpin the GEM object only after freeing the sg table.

Signed-off-by: Christian König christian.koenig@amd.com

drivers/gpu/drm/drm_prime.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index e82a976f0fba..c38dacda6119 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -230,26 +230,26 @@ void drm_gem_map_detach(struct dma_buf *dma_buf, struct drm_prime_attachment *prime_attach = attach->priv; struct drm_gem_object *obj = dma_buf->priv; struct drm_device *dev = obj->dev;

• struct sg_table *sgt;

• if (dev->driver->gem_prime_unpin)

• dev->driver->gem_prime_unpin(obj);
  

• if (prime_attach) {

• struct sg_table *sgt = prime_attach->sgt;
  
  

• if (!prime_attach)

• return;
  

• sgt = prime_attach->sgt;
• if (sgt) {

• if (prime_attach->dir != DMA_NONE)
  

• 	dma_unmap_sg_attrs(attach->dev, sgt->sgl, sgt->nents,
  

• 			   prime_attach->dir,
  

• 			   DMA_ATTR_SKIP_CPU_SYNC);
  

• sg_free_table(sgt);
  

• if (sgt) {
  

• 	if (prime_attach->dir != DMA_NONE)
  

• 		dma_unmap_sg_attrs(attach->dev, sgt->sgl,
  

• 				   sgt->nents,
  

• 				   prime_attach->dir,
  

• 				   DMA_ATTR_SKIP_CPU_SYNC);
  

• 	sg_free_table(sgt);
  

• }
  

• kfree(sgt);
  

• kfree(prime_attach);
  

• attach->priv = NULL;
  

  }

• kfree(sgt);
• kfree(prime_attach);
• attach->priv = NULL;

• if (dev->driver->gem_prime_unpin)

• dev->driver->gem_prime_unpin(obj);
  

  } EXPORT_SYMBOL(drm_gem_map_detach);