Date: Fri, 10 Apr 2009 00:58:20 +0200
From: Alessandro Zummo <alessandro.zummo@towertech.it>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Atsushi Nemoto <anemo@mba.ocn.ne.jp>, rtc-linux@googlegroups.com,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] rtc: Make rtc_update_irq callable with irqs enabled
Message-ID: <20090410005820.4fcfcc1f@i1501.lan.towertech.it>
In-Reply-To: <20090409153921.04b6384c.akpm@linux-foundation.org>
References: <1239036633-10032-1-git-send-email-anemo@mba.ocn.ne.jp>
	<20090409153921.04b6384c.akpm@linux-foundation.org>
Organization: Tower Technologies
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On Thu, 9 Apr 2009 15:39:21 -0700
Andrew Morton <akpm@linux-foundation.org> wrote:

> > The rtc_update_irq() might be called with irqs enabled, if a interrupt
> > handler was registered without IRQF_DISABLED.  
> 
> Why?  What are the consequences of not merging the patch?  Is it a
> bugfix?  If so, what are the user-visible effects of the bug?

 rtc_update_irq() is called by a driver, and a driver
 is supposed to know when it's doing the call.

 The driver can either use IRQF_DISABLED or disable the
 interrupts in some other ways. 

 I also suspect this is some legacy we are carrying on, 
 so it's better to leave the decision on the interrupt
 handling to the driver itself.

 Unless I'm missing something.

-- 

 Best regards,

 Alessandro Zummo,
  Tower Technologies - Torino, Italy

  http://www.towertech.it

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