>
> > > For userland<->kernel transactions we have the console_semaphore to
> > > protect us. It is also used for console_callback. The console_semaphore is
> > > not used internally to protect global variables :-( To do this properly
> > > would take quite a bit of work.
> >
> > It looks like all these globals need a lock -- they can race on SMP or
> > with kernel preemption.
> >
> > Is it really going to be that hard to wrap a lock around their access,
> > because I think this is going to bite SMP users.
>
> For things like fg_console and currcon it will be. Those variables are
> used everyway like mad. That is a whole lot of locks. I doubt this issue
> will be solved until 2.7.X.
Given that it has just become easy to replicate, I suspect that it will
get fixed by someone looking at the recent changes. Agreed, a perfect fix
may wait, but when preempt fails regularly and SMP works, as described in
posts and by some mail, I don't think a rewrite is needed, just one or a
few locks.
My guess only.
-- bill davidsen <davidsen@tmr.com> CTO, TMR Associates, Inc Doing interesting things with little computers since 1979.- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/