Re: Linux 2.5.71 - random console corruption

From: Gerhard Mack (
Date: Tue Jun 17 2003 - 20:50:54 EST

On Tue, 17 Jun 2003, James Simmons wrote:

> > > 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.

Interestingly enough it's not console switching that does it.. it's
scrolling also as I mentioned before it's not just with preempt enabled.

I wonder if theres another problem somewhere?


Gerhard Mack

<>< As a computer I find your faith in technology amusing.

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