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Date: Thu, 25 Mar 2010 12:42:20 -0700 (PDT)
Message-Id: <20100325.124220.258885098.davem@davemloft.net>
To: torvalds@linux-foundation.org
Cc: mingo@elte.hu, peterz@infradead.org, tglx@linutronix.de,
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Subject: Re: [PATCH] Prevent nested interrupts when the IRQ stack is near
 overflowing v2
From: David Miller <davem@davemloft.net>
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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Thu, 25 Mar 2010 12:10:22 -0700 (PDT)

> 
> 
> On Thu, 25 Mar 2010, Ingo Molnar wrote:
>> 
>> So the patch below should at most trigger bugs in areas that need fixing 
>> anyway, and i'm quite sure that under no circumstance would it cause 
>> unforeseen problems in 'thousands of drivers'.
> 
> If we do this, then we should just remove all the IRQF_DISABLED code in 
> kernel/irq/manage.c too, and basically make IRQF_DISABLED a clear no-op 
> (still leave it around as a #define, to not break any users). 

FWIW, I'm currently using IRQF_DISABLED for virtual network
device interrupts on sparc64 as a workaround for some stack
overflow issues.

This change will just force me to work harder to find out a better way
to fix the problem, so don't let my issue hold this back, it's just
an FYI...