Re: [PATCH] acpi: cpuhp: fix guest-visible maximum access size to the legacy reg block

[Christian Ehrhardt]

On Thu, Jan 5, 2023 at 8:14 AM Laszlo Ersek <lersek@redhat.com> wrote:
>
> On 1/4/23 13:35, Michael S. Tsirkin wrote:
> > On Wed, Jan 04, 2023 at 10:01:38AM +0100, Laszlo Ersek wrote:
> >> The modern ACPI CPU hotplug interface was introduced in the following
> >> series (aa1dd39ca307..679dd1a957df), released in v2.7.0:
> >>
> >>   1  abd49bc2ed2f docs: update ACPI CPU hotplug spec with new protocol
> >>   2  16bcab97eb9f pc: piix4/ich9: add 'cpu-hotplug-legacy' property
> >>   3  5e1b5d93887b acpi: cpuhp: add CPU devices AML with _STA method
> >>   4  ac35f13ba8f8 pc: acpi: introduce AcpiDeviceIfClass.madt_cpu hook
> >>   5  d2238cb6781d acpi: cpuhp: implement hot-add parts of CPU hotplug
> >>                   interface
> >>   6  8872c25a26cc acpi: cpuhp: implement hot-remove parts of CPU hotplug
> >>                   interface
> >>   7  76623d00ae57 acpi: cpuhp: add cpu._OST handling
> >>   8  679dd1a957df pc: use new CPU hotplug interface since 2.7 machine type
> >>
...
>
> The solution to the riddle

Hi,
just to add to this nicely convoluted case an FYI to everyone involved
back then,
the fix seems to have caused a regression [1] in - as far as I've
found - an edge case.

[1]: https://gitlab.com/qemu-project/qemu/-/issues/1520

...

> Laszlo
>
>


-- 
Christian Ehrhardt
Senior Staff Engineer, Ubuntu Server
Canonical Ltd