From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752096AbcKGJJM (ORCPT ); Mon, 7 Nov 2016 04:09:12 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:38804 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750977AbcKGJJJ (ORCPT ); Mon, 7 Nov 2016 04:09:09 -0500 Date: Mon, 7 Nov 2016 10:09:17 +0100 From: Greg Kroah-Hartman To: Eugene Korenevsky Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, Luiz Capitulino , Linus Torvalds , Chase Metzger , Alan Stern , Mathias Nyman , Lu Baolu , Oliver Neukum , Hans Yang Subject: Re: [PATCH v2] USB hub_probe: remove ugly goto-into-compound-statement Message-ID: <20161107090917.GA4949@kroah.com> References: <20161102175944.GA31229@vnote> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20161102175944.GA31229@vnote> User-Agent: Mutt/1.7.1 (2016-10-04) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 02, 2016 at 08:59:44PM +0300, Eugene Korenevsky wrote: > Rework smelling code (goto inside compound statement). Perhaps this is legacy. > Anyway such code is not appropriate for Linux kernel. > > Signed-off-by: Eugene Korenevsky > --- > drivers/usb/core/hub.c | 24 +++++++++++------------- > 1 file changed, 11 insertions(+), 13 deletions(-) What changed from v1? > > diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c > index cbb1467..4081672 100644 > --- a/drivers/usb/core/hub.c > +++ b/drivers/usb/core/hub.c > @@ -1802,23 +1802,21 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) > > /* Some hubs have a subclass of 1, which AFAICT according to the */ > /* specs is not defined, but it works */ > - if ((desc->desc.bInterfaceSubClass != 0) && > - (desc->desc.bInterfaceSubClass != 1)) { > -descriptor_error: > + > + /* Reject in following cases: > + * - Interface subclass is not 0 or 1 > + * - Multiple endpoints > + * - Not an interrupt in endpoint > + */ > + endpoint = &desc->endpoint[0].desc; > + if ((desc->desc.bInterfaceSubClass != 0 && > + desc->desc.bInterfaceSubClass != 1) || > + desc->desc.bNumEndpoints != 1 || > + !usb_endpoint_is_int_in(endpoint)) { > dev_err(&intf->dev, "bad descriptor, ignoring hub\n"); > return -EIO; > } > > - /* Multiple endpoints? What kind of mutant ninja-hub is this? */ > - if (desc->desc.bNumEndpoints != 1) > - goto descriptor_error; > - > - endpoint = &desc->endpoint[0].desc; > - > - /* If it's not an interrupt in endpoint, we'd better punt! */ > - if (!usb_endpoint_is_int_in(endpoint)) > - goto descriptor_error; > - As "horrible" as the original code might be, it's much easier to read and follow, which is the key thing here, right? What's so bad about a goto backwards? thanks, greg k-h