On 2012-09-20 15:01, Gilles Chanteperdrix wrote: > On 09/20/2012 01:15 PM, Jan Kiszka wrote: > >> On 2012-09-20 12:57, Jan Kiszka wrote: >>> On 2012-09-20 12:56, Jan Kiszka wrote: >>>> On 2012-09-20 12:49, Philippe Gerum wrote: >>>>> On 09/20/2012 12:37 PM, Jan Kiszka wrote: >>>>>> This reverts commit 073ff1e8045d0311b8cf390687c0ba3619681672. >>>>>> >>>>>> Both service are NOT just root-only services. E.g., rtdm_irq_request >>>>>> requires by specification support also over non-Linux contexts. >>>>> >>>>> Nack. We can't run the enable code for MSIs over non-root, and >>>>> that code typically follows the irq request. Besides, we want to mask >>>>> the source upon irq free to handle the SMP case properly, which we could >>>>> not do from non-root with MSIs. >>>>> >>>>> So either we have both request+enable and free usable over non-root, or >>>>> there is no point. >>>> >>>> OK, I get the point with legacy MSI. Then we have two other bugs to solve: >>>> - in I-pipe as it holds a hardened spin lock across enable/disable (of >>>> MSIs) >> >> I think this bug may only manifest over ARM as that arch does >> enable/disable_irq() inside __ipipe_enable/disable_irqdesc - unless >> something prevents that enabling will ever happen for interrupts that >> need Linux locks to work. Is that assured? > > > ARM does that because otherwise interrupts are not enabled after a call > to eg. rtdm_irq_request, and calling rtdm_irq_enable does not work, > calling request_irq is required to get them working.
The generic pattern Xenomai currently uses is xnintr_attach + xnintr_enable. The latter happens to be rtdm_irq_enable as well. So, doesn't xnintr_enable work at all? Or is it only not suited as interrupt startup? Then, is that a new issue or something core-3.x specific? Finally, can't we address it in xnarch_enable_irq? Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux _______________________________________________ Xenomai mailing list Xenomai@xenomai.org http://www.xenomai.org/mailman/listinfo/xenomai
