Re: [PATCH 5/9] dma-mapping: support highmem in the generic remap allocator
From: Christoph Hellwig
Date: Tue Dec 04 2018 - 09:23:10 EST
On Tue, Dec 04, 2018 at 09:38:02AM +0100, Marek Szyprowski wrote:
> Hi All,
>
> On 2018-11-30 20:05, Robin Murphy wrote:
> > On 05/11/2018 12:19, Christoph Hellwig wrote:
> >> By using __dma_direct_alloc_pages we can deal entirely with struct page
> >> instead of having to derive a kernel virtual address.
> >
> > Simple enough :)
> >
> > Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
>
> This patch has landed linux-next yesterday and I've noticed that it
> breaks operation of many drivers. The change looked simple, but a stupid
> bug managed to slip into the code. After a short investigation I've
> noticed that __dma_direct_alloc_pages() doesn't set dma_handle and zero
> allocated memory, while dma_direct_alloc_pages() did. The other
> difference is the lack of set_memory_decrypted() handling.
>
> Following patch fixes the issue, but maybe it would be better to fix it
> in kernel/dma/direct.c:
Thanks for spotting this Marek. Can you send the patch below with a
signoff and a changelog so that I can queue it up?