From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next v6 02/10] dpaa_eth: add support for DPAA Ethernet Date: Mon, 07 Nov 2016 10:55:00 -0500 (EST) Message-ID: <20161107.105500.43380129278294700.davem@davemloft.net> References: <1478117854-8952-3-git-send-email-madalin.bucur@nxp.com> <20161103.155816.642712588084106823.davem@davemloft.net> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, oss@buserror.net, ppc@mindchasers.com, joe@perches.com, pebolle@tiscali.nl, joakim.tjernlund@transmode.se To: madalin.bucur@nxp.com Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Madalin-Cristian Bucur Date: Mon, 7 Nov 2016 15:43:26 +0000 >> From: David Miller [mailto:davem@davemloft.net] >> Sent: Thursday, November 03, 2016 9:58 PM >> >> Why? By clearing this, you disallow an important fundamental way to do >> performane testing, via pktgen. > > The Tx path in DPAA requires one to insert a back-pointer to the skb into > the Tx buffer. On the Tx confirmation path the back-pointer in the buffer > is used to release the skb. If Tx buffer is shared we'd alter the back-pointer > and leak/double free skbs. See also Then have your software state store an array of SKB pointers, one for each TX ring entry, just like every other driver does.