Re: [PATCH] uio_pci_generic does not export memory resources

Jan Kiszka
2012-06-08T13:17:09Z

On 2012-06-08 15:03, Michael S. Tsirkin wrote:
>> + /* set master */
>> + pci_set_master(pdev);
>> +
>> + /* set DMA mask */
>> + err = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
>
> uio currently only supports devices which do not
> do DMA.
>
> DMA from uio controlled devices is a no no unless
> it's behind an IOMMU which can protect us from
> random memory corruptions this could cause.
>
> In the later case it's OK but we need some code
> to check this and program the IOMMU appropriately.

AKA: VFIO. :)

Dominic, maybe you want to have a look at Alex's work:
https://github.com/awilliam/linux-vfio

Jan

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