From: Konrad Rzeszutek Wilk <konrad.w...@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.w...@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.jack...@eu.citrix.com> > Signed-off-by: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> Acked-by: David S. Miller <da...@davemloft.net> -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
