From mboxrd@z Thu Jan  1 00:00:00 1970
From: Joe Perches <joe@perches.com>
Subject: Re: qla3xxx: Odd likely incorrect use of test_bit in qla3xxx.c
Date: Thu, 14 May 2015 01:22:57 -0700
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Cc: Ron Mercer <ron.mercer@qlogic.com>, linux-driver@qlogic.com,
	netdev <netdev@vger.kernel.org>
To: Dan Carpenter <dan.carpenter@oracle.com>
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On Thu, 2015-05-14 at 11:01 +0300, Dan Carpenter wrote:
> On Wed, May 13, 2015 at 10:34:51AM -0700, Joe Perches wrote:
> > In case the patches you found weren't of this type,
> > there are other possibly suspicious uses with & like:
> > drivers/usb/host/ehci-tegra.c:		set_bit((wIndex & 0xff) - 1, &ehci->suspended_ports);
> That's puzzling, yes, but my instinct without looking at the context is
> that it's probably valid.

It may be valid, but at a minimum it's bad code.

Assuming wIndex is guaranteed non-zero, it likely
should be something like:

(wIndex % BITS_PER_LONG) - 1

or suspended_ports should be more than a single ulong

Anyway, thanks.