Re: possible showstopper: kbdmux hangs -current

On 7/31/07, Dmitry Morozovsky <marck_at_rinet.ru> wrote:
> On Mon, 30 Jul 2007, Maksim Yevmenkin wrote:
>
> MY> > MY> > on some of my mobos -current hangs early (when starning init) if kbdmux is
> MY> > MY> > included in kernel (both on i386 and amd64); this seems to be some race, as
> MY> > MY> > hangs are not 100% reproducible. What info should I provide to debug?
> MY> > MY>
> MY> > MY> the usual suspects are
> MY> > MY>
> MY> > MY> 1) while (KBDMUX_CHECK_CHAR(kbd)) { ... } loop in kbdmux_kbd_event().
> MY> > MY> could you please try to put some debug printf's into it and make sure
> MY> > MY> it does not stuck there.
> MY> >
> MY> > errrm. Added two printfs with ppsratecheck - and, as usual, 'specialist
> MY> > presense effect' is in place: no single hang since, both on stock GENERIC and
> MY> > my own stripped down kernel so far (approx 20 reboots).
> MY> >
> MY> > Will try further.
> MY>
> MY> if you remove your debug code and recompile kbdmux(4), does your
> MY> problem re-appear?
>
> Grrm. It does not (yet).

ok. i have to ask.

1) are you using any non-standard compiler options?

2) how are you building new kernel? (or rather do you use NO_CLEAN or
something like that?)

kbdmux(4) has not been changed for awhile. while i completely accept
possibility of bug in kbdmux(4), i find it somewhat strange that it
does not manifest itself all the time.

thanks,
max