Re: iwlwifi problem with iommu/intel-iommu: Enable CONFIG_DMA_DIRECT_OPS=y and clean up intel_{alloc,free}_coherent()

From: Fabio Coatti
Date: Mon Jul 02 2018 - 14:23:10 EST


On Monday 2 July 2018 15:19:51 CEST Christoph Hellwig wrote:
> > By reverting this commit the card works again, tested in 4.17.3 . I've
> > noticed that the corresponding amd commit (
> > b468620f2a1dfdcfddfd6fa54367b8bcc1b51248) has been reverted in linus tree
> > (e16c4790de39dc861b749674c2a9319507f6f64f), and 4.16.X stable tree iirc,
> > but the intel one has not been reverted.
> >
> > hw: Lenovo P50 Intel(R) Core(TM) i7-6820HQ CPU @ 2.70GHz
> >
> > Please let me know if more details are needed, but CC: me as I'm not
> > currently subscribed to LKML.
>
> It probablty is the same issue. Did you check if you can just revert
> the commit cleanly on top of current mainline and that fixes the issue
> for you?

Yep, it does. I issued a
git revert d657c5c73ca987214a6f9436e435b34fc60f332a
on mainline (4.18-rc3) and recompiled, the card works just fine.