From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vlad Zolotarov <vladz@cloudius-systems.com>
Subject: Re: Having troubles binding an SR-IOV VF to
 uio_pci_generic on Amazon instance
Date: Wed, 30 Sep 2015 15:16:04 +0300
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On 09/30/15 15:03, Michael S. Tsirkin wrote:
> On Wed, Sep 30, 2015 at 02:53:19PM +0300, Vlad Zolotarov wrote:
>>
>> On 09/30/15 14:41, Michael S. Tsirkin wrote:
>>> On Wed, Sep 30, 2015 at 02:26:01PM +0300, Vlad Zolotarov wrote:
>>>> The whole idea is to bypass kernel. Especially for networking...
>>> ... on dumb hardware that doesn't support doing that securely.
>> On a very capable HW that supports whatever security requirements needed
>> (e.g. 82599 Intel's SR-IOV VF devices).
> Network card type is irrelevant as long as you do not have an IOMMU,
> otherwise you would just use e.g. VFIO.

Sorry, but I don't follow your logic here - Amazon EC2 environment is a 
example where there *is* iommu but it's not virtualized and thus VFIO is 
useless and there is an option to use directly assigned SR-IOV 
networking device there where using the kernel drivers impose a 
performance impact compared to user space UIO-based user space kernel 
bypass mode of usage. How is it irrelevant? Could u, pls, clarify your 
point?

>
>>> Colour me unimpressed.
>>>