On 08/09/2018 01:11 PM, Logan Gunthorpe wrote:
On 09/08/18 01:47 PM, Kit Chow wrote:
I haven't tested this scenario but my guess would be that IOAT would
indeed go through the IOMMU and the PCI BAR address would need to be
properly mapped into the IOAT's IOVA. The fact that you see DMAR errors
is probably a good indication that this is the case. I really don't know
why you'd want to DMA something without mapping it.
I have experimented with changing ntb_async_tx_submit to dma_map the PCI
BAR
address. With this, I get a different DMAR error:
What code did you use to do this?
If you mean version of linux, it is 4.15.7. Or specific dma_map call, I
believe it was dma_map_single.
DMAR: [DMA Write] Request device [07:00.4] fault addr ffd00000
[fault reason 12] non-zero reserved fields in PTE
Also, what device corresponds to 07:00.4 on your system?
I believe 07.00.4 was the PLX dma device. I get the same error with ioat.
Kit
Logan
