Re: next-0519 on thinkpad x60: sound related? window manager crash

From: Christoph Hellwig
Date: Tue Jun 09 2020 - 07:41:06 EST


On Tue, Jun 09, 2020 at 01:38:46PM +0200, Takashi Iwai wrote:
> On Tue, 09 Jun 2020 13:31:23 +0200,
> Christoph Hellwig wrote:
> >
> > On Tue, Jun 09, 2020 at 11:31:20AM +0200, Takashi Iwai wrote:
> > > > > How would be a proper way to get the virtually mapped SG-buffer pages
> > > > > with coherent memory? (Also allowing user-space mmap, too)
> > > >
> > > > dma_mmap_coherent / dma_mmap_attrs for userspace. We don't really
> > > > have a good way for kernel space mappings.
> > >
> > > And that's the missing piece right now... :-<
> >
> > Can you point me to the relevant places (allocation and vmap mostly)
> > so that I can take a look at how to fix this mess?
>
> Found in sound/core/sgbuf.c. It's specific to x86.

So it looks like we could just turn off CONFIG_SND_DMA_SGBUF and
be done with it? After all this works on other architectures
just fine..