Re: 2.6.10-mm1 hang

From: Badari Pulavarty
Date: Thu Jan 20 2005 - 11:06:20 EST


I see different behaviours on different architectures.

i386 - machine hang
Power5 ppc64 - only the process hang
Power3 ppc64 - machine hang

I modified it to use spin_lock() instead of spin_lock_irq() -
things are the way I was expecting. Only process hang, not
the system.

You may be right on other CPUs stuck on IPI.

Thanks,
Badari

On Wed, 2005-01-19 at 13:31, Andrew Morton wrote:
> Badari Pulavarty <pbadari@xxxxxxxxxx> wrote:
> >
> > I was playing with kexec+kdump and ran into this on 2.6.10-mm1.
> > I have seen similar behaviour on 2.6.10.
> >
> > I am using a 4-way P-III machine. I have a module which tries
> > gets same spinlock twice. When I try to "insmod" this module,
> > my system hangs. All my windows froze, no more new logins,
> > console froze, doesn't respond to sysrq. I wasn't expecting
> > a system hang. Why ? Ideas ?
> >
>
> Maybe all the other CPUs are stuck trying to send an IPI to this one? An
> NMI watchdog trace would tell.
>
> > #include <linux/init.h>
> > #include <asm/uaccess.h>
> > #include <linux/spinlock.h>
> > spinlock_t mylock = SPIN_LOCK_UNLOCKED;
> > static int __init panic_init(void)
> > {
> > spin_lock_irq(&mylock);
> > spin_lock_irq(&mylock);
> > return 1;
> > }
>

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/