Re: Unable to do IA64 stacktrace in early boot

From: Matthew Wilcox <matthew_at_wil.cx>
Date: 2006-12-21 16:03:47
On Thu, Dec 21, 2006 at 02:56:10PM +1100, Keith Owens wrote:
>                     double unlock:  ok  |  ok  |failed|WARNING at /build/kaos/kernel.org-sgidev/linux/kernel/mutex-debug.c:83 debug_mutex_unlock()
> Unable to handle kernel NULL pointer dereference (address 0000000000000000)
> 
> mutex-debug uses DEBUG_LOCKS_WARN_ON() which indirectly calls
> dump_stack which the IA64 unwind code (arch/ia64/kernel/unwind.c) calls
> kmalloc.  The lockdep tests are run before the slab caches have been
> allocated so cpu_cache_get is called with a NULL cachep, hence the
> oops.

Yup.  I just debugged and fixed the same problem on parisc.  I didn't
think to check ia64; I checked to see what x86-64 did.  Unfortunately,
the ia64 unwind code seems a lot more subtle and more allocation-happy
than the parisc unwind code, so I'm not sure exactly how to fix ia64.

-
To unsubscribe from this list: send the line "unsubscribe linux-ia64" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Received on Thu Dec 21 16:04:26 2006

This archive was generated by hypermail 2.1.8 : 2006-12-21 16:04:38 EST