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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 4D69DC43603 for ; Wed, 23 Dec 2020 03:03:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 37B7420705 for ; Wed, 23 Dec 2020 03:03:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728671AbgLWCTe (ORCPT ); Tue, 22 Dec 2020 21:19:34 -0500 Received: from mail.kernel.org ([198.145.29.99]:46280 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728665AbgLWCTe (ORCPT ); Tue, 22 Dec 2020 21:19:34 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id CF4F722573; Wed, 23 Dec 2020 02:18:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1608689940; bh=CmCTXlo5QOeMaTIF2kxMvmLAeNqkCnl3FUaR/jTtx0U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=r5zcuA2IYTU6f8inH9SsD4vYIVn0pgec+lKsgSElGOqslJz+KIi/t6/w4XOk40ISP PXT1dOfhy+70MCAKunxVbMZQyRrJRy0aPsCQdLJpZYBAj1vHY3aY4PrLDIrsMOeG9y 9B/UOQn7JCvUW6345PUxjCE6m3DEdrYLbDh7ecTNF+IOw6roFeshkffhAemHLqH4be 2wb8zXg/a/gbPPMlJyse6Z01USZbvVcLis1VSBA7oDdSuLRmcxPGpawZIDp9XHfMuh 2mpXAsPODxZn6UvtMpgW5LNeAj4LrxAnqo/jtN9uUjdGc5X9MNTUsSVUxdNx9XNaXu N6YCtiOa2bD1Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Heiner Kallweit , Jakub Kicinski , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 036/130] r8169: use READ_ONCE in rtl_tx_slots_avail Date: Tue, 22 Dec 2020 21:16:39 -0500 Message-Id: <20201223021813.2791612-36-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201223021813.2791612-1-sashal@kernel.org> References: <20201223021813.2791612-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Heiner Kallweit [ Upstream commit 95f3c5458dfa5856bb110e31d156e00d894d0134 ] tp->dirty_tx and tp->cur_tx may be changed by a racing rtl_tx() or rtl8169_start_xmit(). Use READ_ONCE() to annotate the races and ensure that the compiler doesn't use cached values. Signed-off-by: Heiner Kallweit Link: https://lore.kernel.org/r/5676fee3-f6b4-84f2-eba5-c64949a371ad@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/realtek/r8169_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c index fd5adb0c54d29..fca8252b4f21d 100644 --- a/drivers/net/ethernet/realtek/r8169_main.c +++ b/drivers/net/ethernet/realtek/r8169_main.c @@ -5856,7 +5856,8 @@ static bool rtl8169_tso_csum_v2(struct rtl8169_private *tp, static bool rtl_tx_slots_avail(struct rtl8169_private *tp, unsigned int nr_frags) { - unsigned int slots_avail = tp->dirty_tx + NUM_TX_DESC - tp->cur_tx; + unsigned int slots_avail = READ_ONCE(tp->dirty_tx) + NUM_TX_DESC + - READ_ONCE(tp->cur_tx); /* A skbuff with nr_frags needs nr_frags+1 entries in the tx queue */ return slots_avail > nr_frags; -- 2.27.0