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=-19.2 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 0232DC4160E for ; Wed, 17 Mar 2021 01:01:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C452B64EBD for ; Wed, 17 Mar 2021 01:01:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231345AbhCQBA4 (ORCPT ); Tue, 16 Mar 2021 21:00:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:36118 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231434AbhCQA7W (ORCPT ); Tue, 16 Mar 2021 20:59:22 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 916E264F8F; Wed, 17 Mar 2021 00:59:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615942762; bh=Coa8wXmQ4nAITFXwC39SY+BgDdXcMylHXeG7flgVsoA=; h=From:To:Cc:Subject:Date:From; b=PKhpymkYWqluE/YlVdJdilKrU1YcwDIjXB13dqnNROStVtQohetMXl5tbqvtETpK8 WakV67+s9S0yuwoGUSM3H+ZHJEHEVWWIB4w8L3J9H6dgkMINmjjkhlJSr6Q277zHoo rAr4IRufmyKoKIKWJRQdk8kAQFW13s2+2btJlgaG3gDc42AS9g4sWF0SkJ8b+M6DpI q7dwl0ZcJ/gp7GPCiqRA3/B/oHihzs9laBe45gxMaZ34VADctOrbzq77xnBONpvHkD zBjxd9DvkIfGBNRaRHP4rSAJb9f7dDS2ucB2Ug5H9rmO9L8Y2WuH/Glyvis6gRIPjy zovpFJNHAoDjQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Heiko Thiery , Richard Cochran , Jakub Kicinski , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 01/21] net: fec: ptp: avoid register access when ipg clock is disabled Date: Tue, 16 Mar 2021 20:59:00 -0400 Message-Id: <20210317005920.726931-1-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Heiko Thiery [ Upstream commit 6a4d7234ae9a3bb31181f348ade9bbdb55aeb5c5 ] When accessing the timecounter register on an i.MX8MQ the kernel hangs. This is only the case when the interface is down. This can be reproduced by reading with 'phc_ctrl eth0 get'. Like described in the change in 91c0d987a9788dcc5fe26baafd73bf9242b68900 the igp clock is disabled when the interface is down and leads to a system hang. So we check if the ptp clock status before reading the timecounter register. Signed-off-by: Heiko Thiery Acked-by: Richard Cochran Link: https://lore.kernel.org/r/20210225211514.9115-1-heiko.thiery@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/freescale/fec_ptp.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/ethernet/freescale/fec_ptp.c b/drivers/net/ethernet/freescale/fec_ptp.c index 6ebad3fac81d..e63df6455fba 100644 --- a/drivers/net/ethernet/freescale/fec_ptp.c +++ b/drivers/net/ethernet/freescale/fec_ptp.c @@ -396,9 +396,16 @@ static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts) u64 ns; unsigned long flags; + mutex_lock(&adapter->ptp_clk_mutex); + /* Check the ptp clock */ + if (!adapter->ptp_clk_on) { + mutex_unlock(&adapter->ptp_clk_mutex); + return -EINVAL; + } spin_lock_irqsave(&adapter->tmreg_lock, flags); ns = timecounter_read(&adapter->tc); spin_unlock_irqrestore(&adapter->tmreg_lock, flags); + mutex_unlock(&adapter->ptp_clk_mutex); *ts = ns_to_timespec64(ns); -- 2.30.1