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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 46AC8C0650F for ; Thu, 8 Aug 2019 19:08:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 17D992173E for ; Thu, 8 Aug 2019 19:08:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565291304; bh=8CrwL/5KPh4jpq0cJdyOmWbgJuCj/OZSfxl+4Ileh7k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=N4dUfmzw/Tr7tQQ2Qv4FcPAlQscsS7CjNeI5xGm8ZH8i9QJ/TFYu+03onFKt5AHrG OAN/xbDrdpKWo5O9ZqKwg/nqSafaKlmGlq8Q/PqtpJyblkrOq6scA4UZQzhBZwkzCL 4eQtDyuNr1HYGejkpGqyXvLgUysRqVz/vu5zUq10= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404897AbfHHTIX (ORCPT ); Thu, 8 Aug 2019 15:08:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:42404 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404882AbfHHTIU (ORCPT ); Thu, 8 Aug 2019 15:08:20 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 A51B5214C6; Thu, 8 Aug 2019 19:08:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565291300; bh=8CrwL/5KPh4jpq0cJdyOmWbgJuCj/OZSfxl+4Ileh7k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SnQQPNIDlIv/7qNniDh7sdgAXTSahGE5aru9IQcMc9TcHkh7PwP1L7LHXk8ah+FDd 4y2+KICa5F2x6xAfz/p0FZvzmbigPVCXL1sAzTta4bsIraEP/pMMX7ovG6l1T2hPAX aY8j51SfOJqO6+Y5iNLx9UjiAybvuTAR9KZb87bQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, liuyonglong , Heiner Kallweit , "David S. Miller" Subject: [PATCH 5.2 47/56] net: phy: fix race in genphy_update_link Date: Thu, 8 Aug 2019 21:05:13 +0200 Message-Id: <20190808190455.068957361@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190808190452.867062037@linuxfoundation.org> References: <20190808190452.867062037@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Heiner Kallweit [ Upstream commit aa6b1956158f1afc52761137620d4b3f8a058d24 ] In phy_start_aneg() autoneg is started, and immediately after that link and autoneg status are read. As reported in [0] it can happen that at time of this read the PHY has reset the "aneg complete" bit but not yet the "link up" bit, what can result in a false link-up detection. To fix this don't report link as up if we're in aneg mode and PHY doesn't signal "aneg complete". [0] https://marc.info/?t=156413509900003&r=1&w=2 Fixes: 4950c2ba49cc ("net: phy: fix autoneg mismatch case in genphy_read_status") Reported-by: liuyonglong Tested-by: liuyonglong Signed-off-by: Heiner Kallweit Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/phy/phy_device.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c @@ -1730,6 +1730,12 @@ done: phydev->link = status & BMSR_LSTATUS ? 1 : 0; phydev->autoneg_complete = status & BMSR_ANEGCOMPLETE ? 1 : 0; + /* Consider the case that autoneg was started and "aneg complete" + * bit has been reset, but "link up" bit not yet. + */ + if (phydev->autoneg == AUTONEG_ENABLE && !phydev->autoneg_complete) + phydev->link = 0; + return 0; } EXPORT_SYMBOL(genphy_update_link);