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Date: Fri, 15 Jun 2007 08:28:57 +0400
From: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
To: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Andrew Morton <akpm@linux-foundation.org>,
       Benjamin Herrenschmidt <benh@kernel.crashing.org>,
       Roland McGrath <roland@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: w1_therm_read_bin: suspicious usage of flush_signals()
Message-ID: <20070615042856.GA22786@2ka.mipt.ru>
References: <20070614172439.GA2468@tv-sign.ru>
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On Thu, Jun 14, 2007 at 09:24:39PM +0400, Oleg Nesterov (oleg@tv-sign.ru) wrote:
> drivers/w1/slaves/w1_therm.c:w1_therm_read_bin()
> 
> 	while (tm) {
> 		tm = msleep_interruptible(tm);
> 		if (signal_pending(current))
> 			flush_signals(current);
> 	}
> 
> current is user-space task, yes?
> 
> this looks just wrong, could you please explain?

Hi Oleg.

Well, it can be uninterruptible sleep, but why?
It is not allowed to return to userspace until transaction is completed,
so having uninterruptible sleep will result in exactly same lost of
signals.

> Oleg.

-- 
	Evgeniy Polyakov