From patchwork Mon Mar 1 16:10:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 389930 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id DAD0EC41621 for ; Mon, 1 Mar 2021 17:35:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C70C56508D for ; Mon, 1 Mar 2021 17:35:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232056AbhCARfC (ORCPT ); Mon, 1 Mar 2021 12:35:02 -0500 Received: from mail.kernel.org ([198.145.29.99]:52092 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238426AbhCAR1E (ORCPT ); Mon, 1 Mar 2021 12:27:04 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 12EF065082; Mon, 1 Mar 2021 16:50:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614617429; bh=YOdh5EiaUA7wRJmPPCou7vees5a19kSHPusgQM1AUis=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2qQV7Po7OB67JZ1h5+ryH9hik/VQpu7qv+qxdCGOJLqqlbap9DLn80BVzW9ZNpRax uiemuYB7fPbIdRzITQlCSUkbAYdop/yB/5v59q6zymCXwHIxSoCLlKHsusciYXnYC0 BUS6Ht7xWe3MM6GT+tsuU5duEnopMbisufAgZ3YE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lijun Pan , Thomas Falcon , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 063/340] ibmvnic: add memory barrier to protect long term buffer Date: Mon, 1 Mar 2021 17:10:07 +0100 Message-Id: <20210301161051.422059075@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161048.294656001@linuxfoundation.org> References: <20210301161048.294656001@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Lijun Pan [ Upstream commit 42557dab78edc8235aba5b441f2eb35f725a0ede ] dma_rmb() barrier is added to load the long term buffer before copying it to socket buffer; and dma_wmb() barrier is added to update the long term buffer before it being accessed by VIOS (virtual i/o server). Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol") Signed-off-by: Lijun Pan Acked-by: Thomas Falcon Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/ibm/ibmvnic.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 5b5d488c2f374..901883a44a320 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -1518,6 +1518,9 @@ static netdev_tx_t ibmvnic_xmit(struct sk_buff *skb, struct net_device *netdev) skb_copy_from_linear_data(skb, dst, skb->len); } + /* post changes to long_term_buff *dst before VIOS accessing it */ + dma_wmb(); + tx_pool->consumer_index = (tx_pool->consumer_index + 1) % tx_pool->num_buffers; @@ -2340,6 +2343,8 @@ restart_poll: offset = be16_to_cpu(next->rx_comp.off_frame_data); flags = next->rx_comp.flags; skb = rx_buff->skb; + /* load long_term_buff before copying to skb */ + dma_rmb(); skb_copy_to_linear_data(skb, rx_buff->data + offset, length);