From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v2 net 1/1] qede: Fix barrier usage after tx doorbell write. Date: Tue, 27 Mar 2018 13:12:16 -0400 (EDT) Message-ID: <20180327.131216.1151106705230717778.davem@davemloft.net> References: <20180327133441.15949-1-manish.chopra@cavium.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, ariel.elior@cavium.com, michal.kalderon@cavium.com To: manish.chopra@cavium.com Return-path: Received: from shards.monkeyblade.net ([184.105.139.130]:43518 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753680AbeC0RMS (ORCPT ); Tue, 27 Mar 2018 13:12:18 -0400 In-Reply-To: <20180327133441.15949-1-manish.chopra@cavium.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Manish Chopra Date: Tue, 27 Mar 2018 06:34:41 -0700 > Since commit c5ad119fb6c09b0297446be05bd66602fa564758 > ("net: sched: pfifo_fast use skb_array") driver is exposed > to an issue where it is hitting NULL skbs while handling TX > completions. Driver uses mmiowb() to flush the writes to the > doorbell bar which is a write-combined bar, however on x86 > mmiowb() does not flush the write combined buffer. > > This patch fixes this problem by replacing mmiowb() with wmb() > after the write combined doorbell write so that writes are > flushed and synchronized from more than one processor. > > V1->V2: > ------- > This patch was marked as "superseded" in patchwork. > (Not really sure for what reason).Resending it as v2. > > Signed-off-by: Ariel Elior > Signed-off-by: Manish Chopra Applied, thank you.