Re: tg3 NIC driver bug in 3.14.x under Xen [and 3 more messages]

[Prashant Sreedharan <prashant@broadcom.com>]

On Fri, 2015-04-17 at 15:12 -0400, David Miller wrote:
> From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> Date: Fri, 17 Apr 2015 15:04:48 -0400
> 
> > From 9e417af099e3cee2b219ab28ffc1e96b0564b213 Mon Sep 17 00:00:00 2001
> > From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> > Date: Fri, 17 Apr 2015 14:55:47 -0400
> > Subject: [PATCH] config: Enable NEED_DMA_MAP_STATE when SWIOTLB is selected
> > 
> > A huge amount of NIC drivers use the DMA API, however if compiled
> > under 32-bit an very important part of the DMA API can be ommitted leading
> > to the drivers not working at all (especially if used with
> > 'swiotlb=force iommu=soft').
> > 
> > As Prashant Sreedharan explains it: "the driver [tg3] uses
> > DEFINE_DMA_UNMAP_ADDR(), dma_unmap_addr_set() to keep a copy of the dma
> > "mapping" and dma_unmap_addr() to get the "mapping" value. On most of
> > the platforms this is a no-op, but ... with "iommu=soft and
> > swiotlb=force" this house keeping is required, ... otherwise
> > we pass 0 while calling pci_unmap_/pci_dma_sync_ instead of the
> > DMA address."
> > 
> > As such enable this even when using 32-bit kernels.
> > 
> > Reported-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
> > Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> 
> Acked-by: David S. Miller <davem@davemloft.net>

Acked-by: Prashant Sreedharan <prashant@broadcom.com>