Re: 2.6.20-rc6-mm3

[Jens Axboe <jens.axboe@oracle.com>]

On Thu, Feb 01 2007, Christoph Lameter wrote:
> On Thu, 1 Feb 2007, Jens Axboe wrote:
> 
> > That looks like barriers, could you try with those disabled? Sorry for
> > making you go through this, I can't debug and fix it myself before
> > monday.
> 
> Disabling barriers + your patch works. Modified /etc/fstab and added a 
> nobarrier option to the root filesystem. If I take your patch out then the 
> systems hangs again.

I can't reproduce this. Can you see if this debug patch catches
anything? You need to enable barriers again.

diff --git a/kernel/sched.c b/kernel/sched.c
index e209901..00c2ab9 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -3434,6 +3434,10 @@ asmlinkage void __sched schedule(void)
 			print_irqtrace_events(current);
 		dump_stack();
 	}
+	if (unlikely(current->io_context && current->io_context->plugged)) {
+		printk(KERN_ERR "%s: schedules plugged\n", current->comm);
+		print_irqtrace_events(current);
+	}
 	profile_hit(SCHED_PROFILING, __builtin_return_address(0));
 
 need_resched:

-- 
Jens Axboe