On 01.03.2019 13:03, Pierre Morel wrote: > On 28/02/2019 15:14, Pierre Morel wrote: >> On 28/02/2019 14:52, Cornelia Huck wrote: >>> On Thu, 28 Feb 2019 14:16:09 +0100 >>> Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote: >>> >>>> On 28/02/2019 12:22, Cornelia Huck wrote: >>> >>>>> So, to summarize, the function should do: >>>>> - Is userspace supposed to emulate everything (!ECA_APIE)? Return >>>>> -EOPNOTSUPP to hand control to it. >>>>> - We are now interpreting the instruction in KVM. Do common checks >>>>> (PSTATE etc.) and inject exceptions, if needed. >>>>> - Now look at the fc; if there's a handler for it, call that; if not >>>>> (case does not attempt to call a specific handler, or no handler >>>>> registered), inject a specification exception. (Do we want pre-checks >>>>> like for facility 65 here, or in the handler?) >>>>> >>>>> That response code 0x01 thingy probably needs to go into the specific >>>>> handler function, if anywhere (don't know the semantics, sorry). >>>> >>>> What do you mean with specific handler function? >>>> >>>> If you mean a switch around the FC with static function's call, I agree, >>>> if you mean a jump into a hook I do not agree. >>> >>> Ah, ok; so each case (that we want to handle) should call into a >>> subhandler that does >>> { >>> (... check things like facilities ...) >>> if (!specific_hook) >>> inject_specif_excp_and_return(); >>> ret = specific_hook(); >>> if (ret) >>> set_resp_code_0x01(); // or in specific_hook()? >>> } >>> >>> ? >> >> Yes something in this direction. > > Sorry, after reflection, no, we do not want to change the previous behavior so we only handle the AQIC case. I think what you wanted to say is the following: Today (without the patch set) we will answer PQAP with an exception. With this patch set we want to handle FC==3, but nothing else. So for anything FC!=3 we will continue to return an exception? Correct?