From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 21 Aug 2013 12:45:11 +0000
Subject: Re: [patch] staging: comedi: comedi_bond: silence a shift wrapping warning
Message-Id: <20130821124511.GZ4713@mwanda>
List-Id: <kernel-janitors.vger.kernel.org>
References: <20130821082727.GB5240@elgon.mountain>
In-Reply-To: <20130821082727.GB5240@elgon.mountain>
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To: kernel-janitors@vger.kernel.org

On Wed, Aug 21, 2013 at 11:50:22AM +0100, Ian Abbott wrote:
> On 2013-08-21 09:27, Dan Carpenter wrote:
> >We set this using:
> >
> >	devs_closed |= (0x1 << bdev->minor)
> >
> >Since 0x1 is an int then only the lower 32 bits are usable before we hit
> >a shift wrapping bug.  There are some static checkers which complain
> >about this.  I've silenced the warning by making devs_closed a 32 bit
> >number.
> >
> >32 bits should be enough for anybody.
> 
> Not really, as bdev->minor will be in the range 0 to 47 inclusive (0
> to COMEDI_NUM_BOARD_MINORS-1).  Of course, an unsigned long is
> insufficient too on a 32-bit system.

Ok.  I'll make it a u64 in a v2 patch.

regards,
dan carpenter