From mboxrd@z Thu Jan  1 00:00:00 1970
From: Hollis Blanchard <hollisb@us.ibm.com>
Subject: Re: [Xen-changelog] [xen-unstable] Add RCU support to Xen.
Date: Wed, 07 Feb 2007 12:57:27 -0600
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To: Jose Renato Santos <jsantos@hpl.hp.com>
Cc: xen-ia64-devel <xen-ia64-devel@lists.xensource.com>, xen-devel <xen-devel@lists.xensource.com>, xen-ppc-devel <xen-ppc-devel@lists.xensource.com>
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On Sat, 2007-01-27 at 13:00 -0800, Xen patchbot-unstable wrote:

> # HG changeset patch
> # User kaf24@localhost.localdomain
> # Date 1169836476 0
> # Node ID 32fd32bbf78d094e96027e3cea05fcbd92fee7a5
> # Parent  19a600376688577f0692eac022f05bc6df30ce93
> Add RCU support to Xen.

...

> @@ -658,6 +659,8 @@ void __init __start_xen(multiboot_info_t
> 
>      trap_init();
> 
> +    rcu_init();
> +    
>      timer_init();
> 
>      early_time_init();

This patch only added the rcu_init() call for x86. When the call is
omitted (on ia64 and powerpc), do_softirq() crashes trying to call a
null function pointer.

In cases like this where you *know* you're going to break the non-x86
architectures, please email xen-ppc-devel and xen-ia64-devel to let us
know what we'll need to do in the future, rather than force us to
reverse-engineer the crash.

Thanks!

-- 
Hollis Blanchard
IBM Linux Technology Center