Re: [PATCH 5.10 11/38] swiotlb: rework "fix info leak with DMA_FROM_DEVICE"

Greg Kroah-Hartman
2022-03-26T10:18:34Z

On Fri, Mar 25, 2022 at 10:08:27AM -0700, Linus Torvalds wrote:
> On Fri, Mar 25, 2022 at 8:09 AM Greg Kroah-Hartman
> <gregkh@linuxfoundation.org> wrote:
> >
> > From: Halil Pasic <pasic@linux.ibm.com>
> >
> > commit aa6f8dcbab473f3a3c7454b74caa46d36cdc5d13 upstream.
>
> This one causes a regression on at least some wireless drivers
> (ath9k). There's some active discussion about it, maybe it gets
> reverted, maybe there are other options.
>
> There's an ath9k patch that fixes the problem, so if this patch goes
> into the stable tree the ath9k fix will follow.
>
> But it might be a good idea to simply hold off on this patch a bit,
> because that ath9k patch hasn't actually landed yet, there's some
> discussion about it all, and it's not clear that other drivers might
> not have the same issue.
>
> So I'm not NAK'ing this patch from stable, but I also don't think it's
> timing-critical, and it might be a good idea to delay it for a week or
> two to both wait for the ath9k patch and to see if something else
> comes up.

Yes, I've been watching that thread. This change is already in 5.15 and
5.16 kernels, and does solve one known security issue, so it's a tough
call. I'll drop them from 5.10 and 5.4 for now and save them to see how
it plays out...

thanks,

greg k-h