Re: [PATCH v2 0/7] dm-integrity: asynchronous hash support

Ingo Franzki
2025-09-09T12:23:39Z

On 09.09.2025 14:15, Milan Broz wrote:
> On 9/9/25 1:50 PM, Ingo Franzki wrote:
>> On 09.09.2025 13:47, Milan Broz wrote:
>>> On 9/9/25 1:18 PM, Ingo Franzki wrote:
>>>>> Please, revert my patches and run the same test on a clean 6.17.0-rc5 just
>>>>> to verify that the patches do not introduce the bug.
>>>>
>>>> With your patches reverted the combined mode fails the same way as with your patches.
>>>> So they did not introduce the bug.
>>>
>>> Please report it as cryptsetup issue with a reproducer so we can later check it.
>>
>> I don't think its a cryptsetup bug, its rather that dm-crypt is missing something to deal with async HMAC ciphers.
>> The point is that PHMAC is a async-only cipher, with no sync variant.
>
> I know, but there is no tracker for dm-crypt and what I like to have some kind of upstream CI testing for PHMAC/PAES
> even without mainframe hw (we already talked about a fake cipher module).
>
> It is not an real issue as PHMAC is neither in released kernel nor in cryptsetup yet, but we should have a test
> coverage once it is merged.

The fake-PHMAC cipher you use for cryptsetup's CI is not async-only, so you won't see this error with it.

>
> On the other side, the async thing is a real pain, is there any plan to switch to something better in future
> (for dm-crypt and dm-integrity)?
>
> Thanks,
> Milan
>
>

--
Ingo Franzki
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