Re: [PATCH v2] Argo: don't obtain excess page references

[Julien Grall <julien@xxxxxxx>]

Hi Jan,

On 14/02/2024 10:12, Jan Beulich wrote:
> find_ring_mfn() already holds a page reference when trying to obtain a
> writable type reference. We shouldn't make assumptions on the general
> reference count limit being effectively "infinity". Obtain merely a type
> ref, re-using the general ref by only dropping the previously acquired
> one in the case of an error.
>
> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Reviewed-by: Julien Grall <jgrall@xxxxxxxxxx>

> ---
> I further question the log-dirty check there: The present P2M type of a
> page doesn't really matter for writing to the page (plus it's stale by
> the time it is looked at). Instead I think every write to such a page
> needs to be accompanied by a call to paging_mark_dirty().
I agree with that.

Cheers,

--
Julien Grall