Re: [RFT][PATCH 2/3] ACPICA: Remove unused memory mappings on interpreter exit

[Dan Williams]

On Sat, Jun 13, 2020 at 12:29 PM Rafael J. Wysocki <rjw@xxxxxxxxxxxxx> wrote:
[,,]
> > While I agree that this is still somewhat suboptimal, improving this
> > would require more changes in the OSL code.
>
> After writing the above I started to think about the extra changes needed
> to improve that and I realized that it would take making the OS layer
> support deferred memory unmapping, such that the unused mappings would be
> queued up for later removal and then released in one go at a suitable time.
>
> However, that would be sufficient to address the issue addressed by this
> series, because the deferred unmapping could be used in
> acpi_ev_system_memory_region_setup() right away and that would be a much
> simpler change than the one made in patch [1/3].
>
> So I went ahead and implemented this and the result is there in the
> acpica-osl branch in my tree, but it hasn't been built yet, so caveat
> emptor.  Anyway, please feel free to have a look at it still.

I'll have a look. However, I was just about to build a test kernel for
the original reporter of this problem with this patch set. Do you want
test feedback on that branch, or this set as is?