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Date: Thu, 25 Mar 2010 16:38:05 +0100
From: Andi Kleen <andi@firstfloor.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <andi@firstfloor.org>, x86@kernel.org,
       LKML <linux-kernel@vger.kernel.org>, jesse.brandeburg@intel.com,
       Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH] Prevent nested interrupts when the IRQ stack is near overflowing v2
Message-ID: <20100325153805.GQ20695@one.firstfloor.org>
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> > Well it's simply the current state of affairs today. I'm merely
> > attempting to make the current state slightly safer without breaking
> > anything in the process.
> 
> Well, I'd agree if those stack overflows would be a massive reported
> problem. 

At least the people who reported it to me thought it was a massive
problem @)

> Right now they happen with a weird test case which points out a
> trouble spot. Multi vector NICs under heavy load. So why not go there
> and change the handful of drivers to run their handlers with irqs
> disabled?

Ok, but afaik it's not that small a number: MSI-X support is getting
more and more wide spread. It's pretty universal in the 10+GbitE space
for space and starts getting deployed for block too.

-Andi
-- 
ak@linux.intel.com -- Speaking for myself only.