From 7ae7ae4ccb87323c5e77e8054337e6cc5009020e Mon Sep 17 00:00:00 2001 From: John Hubbard Date: Thu, 30 Jan 2020 22:12:50 -0800 Subject: [PATCH] media/v4l2-core: set pages dirty upon releasing DMA buffers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit commit 3c7470b6f68434acae459482ab920d1e3fabd1c7 upstream. After DMA is complete, and the device and CPU caches are synchronized, it's still required to mark the CPU pages as dirty, if the data was coming from the device. However, this driver was just issuing a bare put_page() call, without any set_page_dirty*() call. Fix the problem, by calling set_page_dirty_lock() if the CPU pages were potentially receiving data from the device. Link: http://lkml.kernel.org/r/20200107224558.2362728-11-jhubbard@nvidia.com Signed-off-by: John Hubbard Reviewed-by: Christoph Hellwig Acked-by: Hans Verkuil Cc: Mauro Carvalho Chehab Cc: Cc: Alex Williamson Cc: Aneesh Kumar K.V Cc: Björn Töpel Cc: Daniel Vetter Cc: Dan Williams Cc: Ira Weiny Cc: Jan Kara Cc: Jason Gunthorpe Cc: Jason Gunthorpe Cc: Jens Axboe Cc: Jerome Glisse Cc: Jonathan Corbet Cc: Kirill A. Shutemov Cc: Leon Romanovsky Cc: Mike Rapoport Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/media/v4l2-core/videobuf-dma-sg.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/media/v4l2-core/videobuf-dma-sg.c b/drivers/media/v4l2-core/videobuf-dma-sg.c index b6189a4958c5..025822bc6941 100644 --- a/drivers/media/v4l2-core/videobuf-dma-sg.c +++ b/drivers/media/v4l2-core/videobuf-dma-sg.c @@ -352,8 +352,11 @@ int videobuf_dma_free(struct videobuf_dmabuf *dma) BUG_ON(dma->sglen); if (dma->pages) { - for (i = 0; i < dma->nr_pages; i++) + for (i = 0; i < dma->nr_pages; i++) { + if (dma->direction == DMA_FROM_DEVICE) + set_page_dirty_lock(dma->pages[i]); put_page(dma->pages[i]); + } kfree(dma->pages); dma->pages = NULL; }