We must make sure our scatterlist segments are not too big, otherwise
we might see swiotlb failures (happens with sev, also reproducable with
swiotlb=force).
Suggested-by: Laszlo Ersek <lersek at redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>
---
drivers/gpu/drm/virtio/virtgpu_object.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c
b/drivers/gpu/drm/virtio/virtgpu_object.c
index b2da31310d24..6e44568813dd 100644
--- a/drivers/gpu/drm/virtio/virtgpu_object.c
+++ b/drivers/gpu/drm/virtio/virtgpu_object.c
@@ -204,6 +204,7 @@ int virtio_gpu_object_get_sg_table(struct virtio_gpu_device
*qdev,
.interruptible = false,
.no_wait_gpu = false
};
+ unsigned max_segment;
/* wtf swapping */
if (bo->pages)
@@ -215,8 +216,13 @@ int virtio_gpu_object_get_sg_table(struct virtio_gpu_device
*qdev,
if (!bo->pages)
goto out;
- ret = sg_alloc_table_from_pages(bo->pages, pages, nr_pages, 0,
- nr_pages << PAGE_SHIFT, GFP_KERNEL);
+ max_segment = virtio_max_dma_size(qdev->vdev);
+ max_segment &= ~(size_t)(PAGE_SIZE - 1);
+ if (max_segment > SCATTERLIST_MAX_SEGMENT)
+ max_segment = SCATTERLIST_MAX_SEGMENT;
+ ret = __sg_alloc_table_from_pages(bo->pages, pages, nr_pages, 0,
+ nr_pages << PAGE_SHIFT,
+ max_segment, GFP_KERNEL);
if (ret)
goto out;
return 0;
--
2.18.1
