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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2C5EC433F5 for ; Sun, 2 Jan 2022 09:00:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231298AbiABIlZ (ORCPT ); Sun, 2 Jan 2022 03:41:25 -0500 Received: from mph.eclipse.net.uk ([81.168.73.77]:55636 "EHLO mint-fitpc2.localdomain" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S229505AbiABIlZ (ORCPT ); Sun, 2 Jan 2022 03:41:25 -0500 Received: from palantir17.mph.net (unknown [192.168.0.102]) by mint-fitpc2.localdomain (Postfix) with ESMTP id 99A34320022; Sun, 2 Jan 2022 08:41:23 +0000 (GMT) Received: from localhost ([::1] helo=palantir17.mph.net) by palantir17.mph.net with esmtp (Exim 4.89) (envelope-from ) id 1n3wQc-0001Vs-VY; Sun, 02 Jan 2022 08:41:23 +0000 Subject: [PATCH v2 net-next] sfc: The RX page_ring is optional From: Martin Habets To: kuba@kernel.org, jiasheng@iscas.ac.cn, davem@davemloft.net Cc: ecree.xilinx@gmail.com, netdev@vger.kernel.org Date: Sun, 02 Jan 2022 08:41:22 +0000 Message-ID: <164111288276.5798.10330502993729113868.stgit@palantir17.mph.net> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org The RX page_ring is an optional feature that improves performance. When allocation fails the driver can still function, but possibly with a lower bandwidth. Guard against dereferencing a NULL page_ring. Fixes: 2768935a4660 ("sfc: reuse pages to avoid DMA mapping/unmapping costs") Signed-off-by: Martin Habets Reported-by: Jiasheng Jiang --- drivers/net/ethernet/sfc/falcon/rx.c | 5 +++++ drivers/net/ethernet/sfc/rx_common.c | 5 +++++ 2 files changed, 10 insertions(+) diff --git a/drivers/net/ethernet/sfc/falcon/rx.c b/drivers/net/ethernet/sfc/falcon/rx.c index 11a6aee852e9..0c6cc2191369 100644 --- a/drivers/net/ethernet/sfc/falcon/rx.c +++ b/drivers/net/ethernet/sfc/falcon/rx.c @@ -110,6 +110,8 @@ static struct page *ef4_reuse_page(struct ef4_rx_queue *rx_queue) struct ef4_rx_page_state *state; unsigned index; + if (unlikely(!rx_queue->page_ring)) + return NULL; index = rx_queue->page_remove & rx_queue->page_ptr_mask; page = rx_queue->page_ring[index]; if (page == NULL) @@ -293,6 +295,9 @@ static void ef4_recycle_rx_pages(struct ef4_channel *channel, { struct ef4_rx_queue *rx_queue = ef4_channel_get_rx_queue(channel); + if (unlikely(!rx_queue->page_ring)) + return; + do { ef4_recycle_rx_page(channel, rx_buf); rx_buf = ef4_rx_buf_next(rx_queue, rx_buf); diff --git a/drivers/net/ethernet/sfc/rx_common.c b/drivers/net/ethernet/sfc/rx_common.c index 0983abc0cc5f..633ca77a26fd 100644 --- a/drivers/net/ethernet/sfc/rx_common.c +++ b/drivers/net/ethernet/sfc/rx_common.c @@ -45,6 +45,8 @@ static struct page *efx_reuse_page(struct efx_rx_queue *rx_queue) unsigned int index; struct page *page; + if (unlikely(!rx_queue->page_ring)) + return NULL; index = rx_queue->page_remove & rx_queue->page_ptr_mask; page = rx_queue->page_ring[index]; if (page == NULL) @@ -114,6 +116,9 @@ void efx_recycle_rx_pages(struct efx_channel *channel, { struct efx_rx_queue *rx_queue = efx_channel_get_rx_queue(channel); + if (unlikely(!rx_queue->page_ring)) + return; + do { efx_recycle_rx_page(channel, rx_buf); rx_buf = efx_rx_buf_next(rx_queue, rx_buf);