Re: [dpdk-dev] [PATCH] eal: pick IOVA as PA if IOMMU is not available

["Burakov, Anatoly" <anatoly.burakov@intel.com>]

On 25-Jul-19 10:35 AM, David Marchand wrote:
> On Thu, Jul 25, 2019 at 11:31 AM Burakov, Anatoly
> <anatoly.burakov@intel.com> wrote:
>>
>> On 25-Jul-19 9:05 AM, David Marchand wrote:
>>> On Wed, Jul 24, 2019 at 6:46 PM Anatoly Burakov
>>> <anatoly.burakov@intel.com> wrote:
>>>>
>>>> When IOMMU is not available, /sys/kernel/iommu_groups will not be
>>>> populated. This is happening since at least 3.6 when VFIO support
>>>> was added. If the directory is empty, EAL should not pick IOVA as
>>>> VA as the default IOVA mode.
>>>>
>>>> We also assume that VFIO equals IOMMU, so if VFIO support is not
>>>> compiled, we always assume IOMMU support is not available.
>>>
>>> Not sure I agree with this statement.
>>> What about unknown (from eal pov) kernel drivers?
>>
>> Are there any cases where we can use IOVA as VA mode without having VFIO
>> compiled?
> 
> If a pmd relies on a kernel driver we don't know in EAL.
> This is not the case afaik, but I'd prefer we don't mix vfio and iommu.
> 

OK, i can drop that.

-- 
Thanks,
Anatoly