From mboxrd@z Thu Jan 1 00:00:00 1970 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=-13.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,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 01520C43387 for ; Fri, 11 Jan 2019 14:54:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C6384206B6 for ; Fri, 11 Jan 2019 14:54:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547218484; bh=+K+CEzHbfyVqI5eFNWJMqwMw+yUDo0XzmvYDS/+yqjA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XJuSsXDSZFfqoLDU031K3jNNknS6LhwHhFH9JFBUgwAIp1Yvsv2BEnpkrtAGRj4Wh yVqjZaf92X/C8qAOcgKVNuN9E/682Ya1PZCN9B9XS1t5huXoIyPTQlGEgBytpIqL5n Z6iOKgUf0SBM7OY1LbJCTpnB/nJ9hDsT4P3ctCYk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391733AbfAKOyn (ORCPT ); Fri, 11 Jan 2019 09:54:43 -0500 Received: from mail.kernel.org ([198.145.29.99]:57778 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390161AbfAKOhS (ORCPT ); Fri, 11 Jan 2019 09:37:18 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 48FAD204EC; Fri, 11 Jan 2019 14:37:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1547217437; bh=+K+CEzHbfyVqI5eFNWJMqwMw+yUDo0XzmvYDS/+yqjA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=u3jUOe9wxjOFNsn272vwnanWSHgmV8Klw8GqZ0kUD2DQ73NECnv1TsQrR6gnLiO84 In0nijHbh8mQ4auOcnjfkXegIay8De2u1z/t8MQKxkrTVXh+nqrk1nO4O7Y4jhTVCN V4st0CYS7aNC/6eZsSNYVbMOhUvU8X3OQk3BCcNc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Anssi Hannula , Harini Katakam , Claudiu Beznea , Nicolas Ferre , Michal Simek , "David S. Miller" , Sasha Levin Subject: [PATCH 4.19 059/148] net: macb: fix random memory corruption on RX with 64-bit DMA Date: Fri, 11 Jan 2019 15:13:57 +0100 Message-Id: <20190111131116.627394872@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190111131114.337122649@linuxfoundation.org> References: <20190111131114.337122649@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit e100a897bf9b19089e57f236f2398c9e0538900e ] 64-bit DMA addresses are split in upper and lower halves that are written in separate fields on GEM. For RX, bit 0 of the address is used as the ownership bit (RX_USED). When the RX_USED bit is unset the controller is allowed to write data to the buffer. The driver does not guarantee that the controller already sees the upper half when the RX_USED bit is cleared, possibly resulting in the controller writing an incoming frame to an address with an incorrect upper half and therefore possibly corrupting unrelated system memory. Fix that by adding the necessary DMA memory barrier between the writes. This corruption was observed on a ZynqMP based system. Fixes: fff8019a08b6 ("net: macb: Add 64 bit addressing support for GEM") Signed-off-by: Anssi Hannula Acked-by: Harini Katakam Tested-by: Claudiu Beznea Cc: Nicolas Ferre Cc: Michal Simek Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/cadence/macb_main.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c index 240fd36b5074..2de9197df074 100644 --- a/drivers/net/ethernet/cadence/macb_main.c +++ b/drivers/net/ethernet/cadence/macb_main.c @@ -682,6 +682,11 @@ static void macb_set_addr(struct macb *bp, struct macb_dma_desc *desc, dma_addr_ if (bp->hw_dma_cap & HW_DMA_CAP_64B) { desc_64 = macb_64b_desc(bp, desc); desc_64->addrh = upper_32_bits(addr); + /* The low bits of RX address contain the RX_USED bit, clearing + * of which allows packet RX. Make sure the high bits are also + * visible to HW at that point. + */ + dma_wmb(); } #endif desc->addr = lower_32_bits(addr); -- 2.19.1