lkml.org 
[lkml]   [2008]   [Jan]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 01/20 -v5] printk - dont wakeup klogd with interrupts disabled
On Wed 2008-01-23 12:25:09, Mathieu Desnoyers wrote:
> * Daniel Walker (dwalker@mvista.com) wrote:
> >
> > On Wed, 2008-01-23 at 11:02 -0500, Steven Rostedt wrote:
> >
> > > + if (!irqs_disabled() && wake_klogd)
> > > wake_up_klogd();
> >
> > This causes a regression .. When printk is called during an OOPS in
> > kernels without this change then the OOPS will get logged, since the
> > logging process (klogd) is woken to handle the messages.. If you apply
> > this change klogd doesn't wakeup, and hence doesn't log the oops.. So if
> > you remove the wakeup here you have to add it someplace else to maintain
> > the logging ..
> >
> > (I'm not theorizing here, I have defects logged against this specific
> > piece of code..)
> >
>
> Can we change this for :
> if (!(irqs_disabled() && !oops_in_progress) && wake_klogd)
> wake_up_klogd();
>
> ?

That's wrong, too.

Just make wake_up_klogd do trylock, if it finds that it can't get
neccessary locks, printk(KERN_ALERT) so at least console gets the
message, but proceed without the lock.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


\
 
 \ /
  Last update: 2008-01-24 14:41    [from the cache]
©2003-2011 Jasper Spaans