Re: [PATCH] x86: enable swiotlb for > 4GiG ram on 32-bit kernels

[Christoph Hellwig]

On Sun, Oct 14, 2018 at 10:13:31AM +0200, Thomas Gleixner wrote:
> On Sun, 14 Oct 2018, Christoph Hellwig wrote:
> 
> > We already build the swiotlb code for 32b-t kernels with PAE support,
> > but the code to actually use swiotlb has only been enabled for 64-bit
> > kernel for an unknown reason.
> > 
> > Before Linux 4.18 we papers over this fact because the networking code,
> > the scsi layer and some random block drivers implenented their own
> > bounce buffering scheme.
> > 
> > Fixes: 21e07dba ("scsi: reduce use of block bounce buffers")
> > Fixes: ab74cfeb ("net: remove the PCI_DMA_BUS_IS_PHYS check in illegal_highdma")
> > Reported-by: tedheadster <tedheadster@xxxxxxxxx>
> > Tested-by: tedheadster <tedheadster@xxxxxxxxx>
> 
> I'll add your SOB when picking this up :)

Thanks.  Here it is in writing:

Signed-off-by: Christoph Hellwig <hch@xxxxxx>