Re: snd_usb_audio OOPS on MIPSEL - is that the mmap issue?

From: Takashi Iwai
Date: Fri Nov 27 2009 - 03:36:29 EST


At Thu, 26 Nov 2009 18:15:54 +0000,
Ralf Baechle wrote:
>
> On Thu, Nov 26, 2009 at 10:09:04AM +0100, Takashi Iwai wrote:
>
> > I guess it won't, because usb audio driver provides its own page
> > callback. It uses vmalloced buffer as the primary buffer, then
> > copies to the urb transfer buffer. So, mmap should work as long as
> > the page returned from vmalloc_to_page() can be mapped.
>
> You mean mapping a page that is mapped to the vmalloc area of the kernel
> also to userland? That's a fairly safe way to create cache aliases on
> those platforms that suffer from them.

Yes. Thanks for clarification!


Takashi
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/