I provided the initial version of the patch to the mailing list:
[PATCH] i386/acpi: restore device paths for pre-5.1 vms

Unfortunately I do not have easy access to a VM where I can test it at the moment. Please make sure that it works for you and reply with `Tested-by`.

Thanks,
Vitaly

> 1 марта 2021 г., в 22:08, Igor Mammedov <imammedo@redhat.com> написал(а):
> 
> 
> On Mon, 1 Mar 2021 17:28:05 +0100
> Laszlo Ersek <lersek@redhat.com> wrote:
> 
>> On 03/01/21 17:14, Michael S. Tsirkin wrote:
>>> On Mon, Mar 01, 2021 at 02:28:19PM +0100, Igor Mammedov wrote:
>> 
>>>> How about:
>>>> * buggy ACPI for 5.1 machine types and older
>>>> * fixed ACPI for 5.2 and newer?
>>> 
>>> Exactly.
>> 
>> Sounds OK to me as well (even though it's quite unfortunate that this is
>> one of those exceptions that require us to version the ACPI generator).
> it is unfortunate, and I do resist to such changes usually.
> in this case, I fill avoiding complaints/bug reports justifies such exception.
> 
> 
>> Thanks
>> Laszlo
>> 
>> 
>