From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@scylladb.com>
Subject: Re: Having troubles binding an SR-IOV VF to
 uio_pci_generic on Amazon instance
Date: Thu, 1 Oct 2015 13:11:28 +0300
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On 10/01/2015 01:07 PM, Michael S. Tsirkin wrote:
> On Thu, Oct 01, 2015 at 12:38:51PM +0300, Avi Kivity wrote:
>> The sad thing is that you can do this since forever on a non-virtualized
>> system, or on a virtualized system if you don't need interrupt support.  All
>> you're doing is blocking interrupt support on virtualized systems.
> True, Linux could do more to prevent this kind of abuse.
> In fact IIRC, if you enable secureboot, it does exactly that.
>
> A generic uio driver isn't a good interface because it relies on these
> sysfs files. We are luckly it doesn't work for VFs, I don't think we
> should do anything that relies on this interface in future applications.
>

I agree that uio is not a good solution.  But for some users, which we 
are discussing now, it is the only solution.

A bad solution is better than no solution.