Re: 2.5 Problem Status Report

[Oleg Drokin <green@namesys.com>]

Hello!

On Wed, Sep 11, 2002 at 04:10:21PM +0400, Oleg Drokin wrote:
> > > > Ok, with other patch it still fails in the same way.
> > > > I have not backed out other patch so I tested with both patches perent.
> > > alright, seems I do have to try it myself... ok will do that.
> > with both patches I sent applied, the bug does _not_ exist here as
> > expected. could you please double check that they are applied, and that
> > you have booted the right kernel? a make clean just to be on the safe
> > side might be a good idea :-)
> Well, now it works for me too. Not sure why it was working previous time,
> because all the patches were in place. I will play more with it later today.

It's me again. And I have bad news.
I have figured why it works for you and did not worked for me.

Try following patch (inspired by Ingo) to get nice BUG on bootup again.

Without the patch ext2 works with your fixes, but reiserfs is not working,
so it seems there are constant preempt counter underflows that later gets
corrected.

Bye,
    Oleg

===== include/linux/preempt.h 1.6 vs edited =====
--- 1.6/include/linux/preempt.h	Fri Sep  6 04:18:30 2002
+++ edited/include/linux/preempt.h	Wed Sep 11 19:28:42 2002
@@ -17,7 +17,8 @@
 
 #define dec_preempt_count() \
 do { \
-	preempt_count()--; \
+	if ( --preempt_count()) \
+		BUG(); \
 } while (0)
 
 #ifdef CONFIG_PREEMPT