From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from charlotte.tuxdriver.com ([70.61.120.58]:53136 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752224Ab0ECSPL (ORCPT ); Mon, 3 May 2010 14:15:11 -0400 Date: Mon, 3 May 2010 14:02:41 -0400 From: "John W. Linville" To: Ben Gamari Cc: Abhijeet Kolekar , linux-wireless@vger.kernel.org, yi.zhu@intel.com Subject: Re: [PATCH V2] mac80211: fix paged defragmentation Message-ID: <20100503180241.GB25748@tuxdriver.com> References: <1272668279-6065-1-git-send-email-abhijeet.kolekar@intel.com> <87hbmsa4bj.fsf@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <87hbmsa4bj.fsf@gmail.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, Apr 30, 2010 at 07:49:52PM -0400, Ben Gamari wrote: > On Fri, 30 Apr 2010 15:57:59 -0700, Abhijeet Kolekar wrote: > > > > diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c > > index 72efbd8..e7217e2 100644 > > --- a/net/mac80211/rx.c > > +++ b/net/mac80211/rx.c > > @@ -1255,6 +1255,7 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) > > if (skb_linearize(rx->skb)) > > return RX_DROP_UNUSABLE; > > > > + hdr = (struct ieee80211_hdr *)rx->skb->data; > > seq = (sc & IEEE80211_SCTL_SEQ) >> 4; > > > It seems to me that this might deserve a comment describing exactly why > hdr needs to be set twice in one function. To the uninformed outsider > the code simply seems redundant. It's unclear semantics like this that > could cause nasty issues when someone goes back for housecleaning. Just > a thought. Not only that, but is there something we need to do to make sure the compiler doesn't think it can optimize away the second assignment of hdr? John -- John W. Linville Someday the world will need a hero, and you linville@tuxdriver.com might be all we have. Be ready.