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From: "Michael S. Tsirkin" <mst@redhat.com>
To: Vladislav Zolotarov <vladz@cloudius-systems.com>
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Subject: Re: [dpdk-dev] [PATCH 2/2] uio: new driver to support PCI MSI-X
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On Tue, Oct 06, 2015 at 01:09:55AM +0300, Vladislav Zolotarov wrote:
> How about instead of trying to invent the wheel just go and attack the problem
> directly just like i've proposed already a few times in the last days: instead
> of limiting the UIO limit the users that are allowed to use UIO to privileged
> users only (e.g. root). This would solve all clearly unresolvable issues u are
> raising here all together, wouldn't it?

No - root or no root, if the user can modify the addresses in the MSI-X
table and make the chip corrupt random memory, this is IMHO a non-starter.

And tainting kernel is not a solution - your patch adds a pile of
code that either goes completely unused or taints the kernel.
Not just that - it's a dedicated userspace API that either
goes completely unused or taints the kernel.

> >
> > --
> > MST
>