Re: [PATCH] usb: misc: usbtest: remove redundant check on retval < 0

From: Alan Stern
Date: Mon Feb 13 2017 - 11:45:37 EST


On Mon, 13 Feb 2017, Felipe Balbi wrote:

> Hi,
>
> Colin King <colin.king@xxxxxxxxxxxxx> writes:
> > From: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> >
> > The check for retval being less than zero is always true since
> > retval equal to -EPIPE at that point. Replace the existing
> > conditional with just return retval.
> >
> > Detected with CoverityScan, CID#114349 ("Logically dead code")
> >
> > Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> > ---
> > drivers/usb/misc/usbtest.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c
> > index 3525626..17c0810 100644
> > --- a/drivers/usb/misc/usbtest.c
> > +++ b/drivers/usb/misc/usbtest.c
> > @@ -992,7 +992,7 @@ static int ch9_postconfig(struct usbtest_dev *dev)
> > dev_err(&iface->dev,
> > "hs dev qualifier --> %d\n",
> > retval);
> > - return (retval < 0) ? retval : -EDOM;
> > + return retval;
>
> you're changing return value here, are you sure there's nothing else
> depending on this error?

I bet you didn't look at the original code. :-) Just before the start
of the patch there is:

if (retval == -EPIPE) {
...

So no, the patch does not change the return value.

Alan Stern