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Date: Wed, 24 Mar 2010 21:42:15 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Andi Kleen <andi@firstfloor.org>
cc: x86@kernel.org, linux-kernel@vger.kernel.org, jesse.brandeburg@intel.com
Subject: Re: [PATCH] Prevent nested interrupts when the IRQ stack is near
 overflowing v2
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B1;2005;0cOn Wed, 24 Mar 2010, Andi Kleen wrote:

> Prevent nested interrupts when the IRQ stack is near overflowing v2
> 
> Interrupts can always nest when they don't run with IRQF_DISABLED.
> 
> When a lot of interrupts hit the same vector on the same
> CPU nested interrupts can overflow the irq stack and cause hangs.
> 
> This has been observed with MSI-X & Ethernet on a large system.

In which way are which interrupts nested ?
 
Thanks,

	tglx