Re: ehci-pci breakage with dma-mapping changes in 5.4-rc2

From: Arvind Sankar
Date: Mon Oct 07 2019 - 13:59:01 EST


On Mon, Oct 07, 2019 at 10:56:30AM -0700, Christoph Hellwig wrote:
> On Mon, Oct 07, 2019 at 07:55:28PM +0200, Christoph Hellwig wrote:
> > On Mon, Oct 07, 2019 at 01:54:32PM -0400, Arvind Sankar wrote:
> > > It doesn't boot with the patch. Won't it go
> > > dma_get_required_mask
> > > -> intel_get_required_mask
> > > -> iommu_need_mapping
> > > -> dma_get_required_mask
> > > ?
> > >
> > > Should the call to dma_get_required_mask in iommu_need_mapping be
> > > replaced with dma_direct_get_required_mask on top of your patch?
> >
> > Yes, sorry.
>
> Actually my patch already calls dma_direct_get_required_mask.
> How did you get the loop?

The function iommu_need_mapping (not changed by your patch) calls
dma_get_required_mask internally, to check whether the device's dma_mask
is big enough or not. That's the call I was asking whether it needs to
be changed.