Re: [PATCH] RDMA/rxe: Pass a pointer to virt_to_page()

Linus Walleij
2023-03-30T15:20:27Z

On Thu, Mar 30, 2023 at 2:06 PM Jason Gunthorpe <jgg@nvidia.com> wrote:
> On Wed, Mar 29, 2023 at 09:45:45PM -0500, Bob Pearson wrote:
> > On 3/29/23 18:16, Jason Gunthorpe wrote:
> > > On Wed, Mar 29, 2023 at 04:28:08PM +0200, Linus Walleij wrote:
> > >
> > >> I'm a bit puzzled: could the above code (which exist in
> > >> three instances in the driver) even work as it is? Or is it not used?
> > >> Or is there some failover from DMA to something else that is constantly
> > >> happening?
> > >
> > > The physical address dma type IB_MR_TYPE_DMA is rarely used and maybe
> > > nobody ever tested it, at least in a configuration where kva != pa
> > >
> > > Then again, maybe I got it wrong and it is still a kva in this case
> > > because it is still ultimately DMA mapped when using IB_MR_TYPE_DMA?
> > >
> > > Bob?
> > >
> > > Jason
> >
> > In the amd64 environment I use to dev and test there is no difference AFAIK.
> > I have to go on faith that other platforms work but have very little experience.
>
> Honestly, I would be much happier if the virtual wrappers used
> physical not kva :\ But that is too much to ask
>
> So I suspsect I got it wrong and it is a kva still

OK I'll respin the first version of the patch but with the quirks making it work
on parisc.

Yours,
Linus Walleij