[vfio-users] New to VFIO, IOMMU

[Alex Williamson]

On Sat, 18 Aug 2018 01:15:02 -0700
Darci Saucedo <dsaucedof5 at gmail.com> wrote:

> Hi there, does anyone have an idea what this problem might be?
> 
> +0.030755] DMAR: [DMA Read] Request device [05:00.0] fault addr 440000000
> [fault reason 06] PTE Read access is not set
> 
> I'm writing a NIC driver with VFIO and IOMMU support. I believe I'm
> doing/setting up everything correctly but when I run my driver I get this
> error.

The error is pretty much as it sounds, device 05:00.0 tried to read
from IOVA address 0x440000000, which is either not mapped or does not
have read permission set in the IOMMU.  IOW, the device is doing a DMA
read from an address you're not expecting or have not correctly mapped
for the device.  Thanks,

Alex