Re: [Intel-gfx] refactor the i915 GVT support

Christoph Hellwig
2021-09-30T05:24:08Z

On Wed, Sep 29, 2021 at 06:27:16PM +0000, Wang, Zhi A wrote:
> Thanks for the idea. I am not sure i915 guys would take this idea since
> that it's only for GVT-g, i915 doesn't use this at all. We need to take
> a snapshot of both PCI configuration space and MMIO registers before
> i915 driver starts to touch the HW.
>
> One idea is we capture the registers in intel_gvt.c during the early
> initialization and do everything else when i915.ko is fully loaded. But
> how about dependence between i915.ko and kvmgt.ko? We cannot do
> request_module("kvmgt") in i915.ko.
>
> Maybe Christoph can give more input on this and how we can deal with
> this? Before we figure out an solution, we have to pick that patch out
> since it blocks our pull request schedule.
>
> Also I was thinking if moving gvt into kvmgt.ko is the right direction.
> It seems the module loading system in kernel is not designed for "module
> A loading module B, which needs symbols from module A, in the
> initialization path of module A".

I have a few idea on how to sort this "deadlock" out. But I'm completely
swamped until the end of next week, so I won't get to anything before
that.