Re: [PATCH v7 08/24] media/v4l2-core: set pages dirty upon releasing DMA buffers
From: Christoph Hellwig <hch@infradead.org>
Date: 2019-11-21 08:11:10
Also in:
bpf, dri-devel, kvm, linux-block, linux-doc, linux-fsdevel, linux-media, linux-mm, linux-rdma, linuxppc-dev, lkml, netdev
On Wed, Nov 20, 2019 at 11:13:38PM -0800, John Hubbard wrote:
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.
Looks good, and like a fix that should be queued up through the media tree for 5.5 and maybe even added to -stable. Reviewed-by: Christoph Hellwig <hch@lst.de>