On 08/03/2017 01:52 PM, Benjamin Herrenschmidt wrote: > On Thu, 2017-08-03 at 19:52 +1000, Michael Ellerman wrote: >> What if num is 0? >> >> Which it would be in the fallback case, if the affinity mask is empty, >> AFAICS. > > How can the mask be empty though ? But yes, as I noted there is a > problem if the value is 0. Not sure what to do if we are given an empty > mask though.
I am seeing different problems. The fuzz value was one but that was due to the fact that the spapr backend did not set the chip_id of the xive_irq_data. I should have fix that now. But in some other situations, the weight of the 'affinity' mask is 2048 (and 'nr_cpu_ids') and that also breaks the 'first' calculation. I am currently tracking this with the xive support for spapr. I will send a fix with the patchset. Thanks, C.