From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH 2/2] ixgbe: check mbuf refcnt when clearing RX/TX ring Date: Fri, 03 Jul 2015 21:52:17 +0200 Message-ID: <15281259.4jgDbnvX5x@xps13> References: <1435938006-22254-1-git-send-email-bruce.richardson@intel.com> <1879755.kzD1mjHoUo@xps13> <20150703160425.GC8096@bricha3-MOBL3> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org To: Bruce Richardson Return-path: Received: from mail-wi0-f179.google.com (mail-wi0-f179.google.com [209.85.212.179]) by dpdk.org (Postfix) with ESMTP id 95D836849 for ; Fri, 3 Jul 2015 21:53:28 +0200 (CEST) Received: by wicgi11 with SMTP id gi11so107620051wic.0 for ; Fri, 03 Jul 2015 12:53:28 -0700 (PDT) In-Reply-To: <20150703160425.GC8096@bricha3-MOBL3> List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 2015-07-03 17:04, Bruce Richardson: > On Fri, Jul 03, 2015 at 05:46:55PM +0200, Thomas Monjalon wrote: > > 2015-07-03 16:40, Bruce Richardson: > > > The function to clear the TX ring when a port was being closed, e.g. on > > > exit in testpmd, was not checking the mbuf refcnt before freeing it. > > > Since the function in the vector driver to clear the ring after TX does > > > not set the pointer to NULL post-free, this caused crashes if mbuf > > > debugging was turned on. > > > > Please, could you add a Fixes: line to reference the origin of the bug? > > Thanks > > What benefit does that information provide? Given that this bug occurs in > two places in the code, and has been there for some time, I'm not sure that a > straight lookup of the commit that last changed the line(s) would identify the > true source of the bug. Because of that, I'd like to know the information is > really going to be useful before making an effort to track it down. :-) If it fixes a bug which was in previous release, it may deserve to be in the release notes. It also helps people wanting to fix the old version they are stuck with. Given it fixes only a crash in debug mode, it's not so important here.