[PATCH 4/4] drm/vgem: flush page during page fault

This is required to use buffers allocated by vgem on AMD and ARM devices. We're experiencing a case where eviction of the cache races with userspace writes. To fix this, flush the cache after retrieving a page.

Signed-off-by: Gurchetan Singh gurchetansingh@chromium.org --- drivers/gpu/drm/vgem/vgem_drv.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c index 35bfdfb746a7..fb263969f02d 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -112,6 +112,7 @@ static int vgem_gem_fault(struct vm_fault *vmf) break; }

+ drm_flush_pages(obj->base.dev->dev, &page, 1); } return ret; }