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Message-ID: <12c511ca0802141817i3295e83cxd7c05e07f2c54fea@mail.gmail.com>
Date: Thu, 14 Feb 2008 18:17:45 -0800
From: "Tony Luck" <tony.luck@gmail.com>
To: "Roland Dreier" <rdreier@cisco.com>
Subject: Re: Strange hang on ia64 with CONFIG_PRINTK_TIME=y
Cc: "David Miller" <davem@davemloft.net>, mingo@elte.hu,
       linux-kernel@vger.kernel.org
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> We *ought* to be safe after cpu_init() ... which is called from setup_arch(),
> which is several calls before sched_init().

Perhaps what is happening is that cpu0 comes online ... safely skips
over the early printk calls.  Calls cpu_init() which sets up the resources
*it* needs (ar.k3 points to per-cpu space), and then executes
sched_init() which marks it safe for all printk's. Then cpu1 comes
up and does a printk before it gets to cpu_init().

Try with Ingo patch and CONFIG_SMP=n to see if you can come
up on a uni-processor.

-Tony