Re: [PATCH v2] drm/prime: fix extracting of the DMA addresses from a scatterlist

[Greg KH]

On Sun, Apr 05, 2020 at 10:47:49AM -0400, Alex Deucher wrote:
> On Fri, Mar 27, 2020 at 12:23 PM Marek Szyprowski
> <m.szyprowski@xxxxxxxxxxx> wrote:
> >
> > Scatterlist elements contains both pages and DMA addresses, but one
> > should not assume 1:1 relation between them. The sg->length is the size
> > of the physical memory chunk described by the sg->page, while
> > sg_dma_len(sg) is the size of the DMA (IO virtual) chunk described by
> > the sg_dma_address(sg).
> >
> > The proper way of extracting both: pages and DMA addresses of the whole
> > buffer described by a scatterlist it to iterate independently over the
> > sg->pages/sg->length and sg_dma_address(sg)/sg_dma_len(sg) entries.
> >
> > Fixes: 42e67b479eab ("drm/prime: use dma length macro when mapping sg")
> > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> > Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
> 
> Applied.  Thanks and sorry for the breakage.


<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>