Re: [PATCH 0/2] target/s390x: Emulate CVDG

[Thomas Huth <thuth@redhat.com>]

On 25/01/2024 13.47, Ilya Leoshkevich wrote:
> On Thu, 2024-01-18 at 18:28 +0100, Thomas Huth wrote:
>> On 15/01/2024 21.21, Ilya Leoshkevich wrote:
>>> Hi,
>>>
>>> Ido reported that we are missing the CVDG emulation (which is very
>>> similar to the existing CVD emulation). This series adds it along
>>> with a test.
>>
>> Just FYI, your patch made me curious which other instructions we
>> still might
>> be missing from chapter 7 in the Principles of Operation... with some
>> shell
>> scripting and manual fiddling, I ended up with this list:
>>
>> 0C	BRANCH AND SAVE AND SET MODE		BASSM
>> 0B	BRANCH AND SET MODE			BSM
>> B21A	COMPARE AND FORM CODEWORD		CFC
>> B257	COMPARE UNTIL SUBSTRING EQUAL		CUSE
>> B263	COMPRESSION CALL			CMPSC
>> 4F	CONVERT TO BINARY (32)			CVB
>> E306	CONVERT TO BINARY (32)			CVBY
>> E30E	CONVERT TO BINARY (64)			CVBG
>> B24D	COPY ACCESS				CPYA
>> EF	LOAD MULTIPLE DISJOINT			LMD
>> EE	PERFORM LOCKED OPERATION		PLO
>> B9BF	TRANSLATE AND TEST EXTENDED		TRTE
>> B9BD	TRANSLATE AND TEST REVERSE EXTENDED	TRTRE
>> 0102	UPDATE TREE				UPT
>>
>> There are some additional ones from the "Guarded-Storage Facility"
>> and the
>> "Transactional-Execution Facility", but these are optional AFAIK.
>>
>> Some of these (like UPT) really look like sins from the CISC past, I
>> guess
>> we'll never need them for running Linux guests :-)
>>
>>    Thomas
>>
> 
> Thanks, I'll append this to my TODO list. At least for CVB* there seems
> to exist an unfinished patch on the list [1].
> 
> [1]
> https://lore.kernel.org/qemu-devel/20180821025104.19604-8-pavel.zbitskiy@gmail.com/

Oh, interesting, there was even a v4 that fixed the review feedback:

https://lore.kernel.org/qemu-devel/20180822144039.5796-4-pavel.zbitskiy@gmail.com/

But it seems like this had fallen through the cracks :-(

Maybe we can re-activate it now...

  Thomas