Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753181AbdLMNxs (ORCPT ); Wed, 13 Dec 2017 08:53:48 -0500 Received: from mail-pl0-f68.google.com ([209.85.160.68]:32967 "EHLO mail-pl0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753130AbdLMNxq (ORCPT ); Wed, 13 Dec 2017 08:53:46 -0500 X-Google-Smtp-Source: ACJfBouVeWurURcM8xcXmM98J4cq16wfLge7oGUTfk5fIyaVuaXrAHWyDIg0wlF5P8QkzfaqGiCR9w== From: Jia-Ju Bai To: akinobu.mita@gmail.com, a.zummo@towertech.it, alexandre.belloni@free-electrons.com Cc: linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH 2/2] rtc-r7301: Fix a possible sleep-in-atomic bug in rtc7301_set_time Date: Wed, 13 Dec 2017 21:56:04 +0800 Message-Id: <1513173364-18424-1-git-send-email-baijiaju1990@gmail.com> X-Mailer: git-send-email 1.7.9.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 861 Lines: 29 The driver may sleep under a spinlock. The function call path is: rtc7301_set_time (acquire the spinlock) usleep_range --> may sleep To fix it, usleep_range is replaced with udelay. This bug is found by my static analysis tool(DSAC) and checked by my code review. Signed-off-by: Jia-Ju Bai --- drivers/rtc/rtc-r7301.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/rtc/rtc-r7301.c b/drivers/rtc/rtc-r7301.c index 28d5408..a040536 100644 --- a/drivers/rtc/rtc-r7301.c +++ b/drivers/rtc/rtc-r7301.c @@ -235,7 +235,7 @@ static int rtc7301_set_time(struct device *dev, struct rtc_time *tm) spin_lock_irqsave(&priv->lock, flags); rtc7301_stop(priv); - usleep_range(200, 300); + udelay(300); rtc7301_select_bank(priv, 0); rtc7301_write_time(priv, tm, false); rtc7301_start(priv); -- 1.7.9.5