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Date: Thu, 7 Jun 2007 19:29:35 -0700 (PDT)
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Steven Rostedt <rostedt@goodmis.org>
cc: Andrew Morton <akpm@linux-foundation.org>,
       LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
       Thomas Gleixner <tglx@linutronix.de>,
       Christoph Hellwig <hch@infradead.org>, Andi Kleen <ak@suse.de>
Subject: Re: [PATCH] enable interrupts in user path of page fault.
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On Thu, 7 Jun 2007, Steven Rostedt wrote:
> 
> I didn't realize that userspace was allowed to run with interrupts
> disabled.

It isn't, normally. You *can* try to do it by using iopl(), but it's not 
practical. It's certainly not practical to expect a page fault to not 
enable them again, since we obviously need interrupts enabled just to 
handle any IO. 

So don't worry about it. 

		Linus