From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Date: Mon, 21 Jan 2002 22:11:49 +0000
Subject: Re: [Linux-ia64] Help with Ingo scheduler on IA64
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To: linux-ia64@vger.kernel.org

On Mon, 21 Jan 2002, David Mosberger wrote:

>   Ingo> we call context_switch() with irqs disabled. The ia64 version
>   Ingo> of switch_to() should not re-enable IRQs or it will deadlock.
>
> The existing switch_to() enables interrupts if the new task's stack is
> on a different (kernel-) page.

oh, i see. Why were irqs enabled explicitly? The old scheduler called
switch_to() with irqs enabled, all the time.

> [...] If the new scheduler guarantees to call switch_to() with irqs
> disabled, we can simply drop the relevant code.

yes. And this should fix the lockup as well.

	Ingo