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=-9.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,T_DKIMWL_WL_HIGH,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 21CC2C28CC0 for ; Thu, 30 May 2019 04:39:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EFA7125928 for ; Thu, 30 May 2019 04:39:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559191159; bh=bYeRNb566ivJGa6XUw7lhUgJLMTq33R8psS/bZAxKNQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=1oGXXuLcTJ0aKJqPZHK1J9oPLrbdNvlVXbzzGqJO+Jc+jY2SxBeKe1KWPX2mhM1F/ 4AjkSqDScgzkp13X20BeHJLDzDZRJ1AJWmcfEUeW5mY+/DDkWzl5l/A56Hld5yPRWY agyJ3jnCdXKHumWgHBrCiCj8/ds98/RkgYrKPLKo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729140AbfE3EjS (ORCPT ); Thu, 30 May 2019 00:39:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:56518 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727857AbfE3DMx (ORCPT ); Wed, 29 May 2019 23:12:53 -0400 Received: from localhost (ip67-88-213-2.z213-88-67.customer.algx.net [67.88.213.2]) (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 D00CA2449A; Thu, 30 May 2019 03:12:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559185972; bh=bYeRNb566ivJGa6XUw7lhUgJLMTq33R8psS/bZAxKNQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AAOL0aF/Rz3oeC646nG4xJ8rgzj0oMEGO4YOOQoAnBd4+IkzQAqQChXuNI0Dnb182 rCjk9Cj5xhHb3mdY++totuDyLNPcSF5YpeDpMVv0roX/NysWLo6ILAbRHbeisjAaax 87sC4WE1GbA/SibTeDyOPRBHFbeWAUy/WF/ooOu8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Adam Thomson , Steve Twiss , Mark Brown , Sasha Levin Subject: [PATCH 5.1 383/405] regulator: lp8755: Fix notifier mutex lock warning Date: Wed, 29 May 2019 20:06:21 -0700 Message-Id: <20190530030600.104456668@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190530030540.291644921@linuxfoundation.org> References: <20190530030540.291644921@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit 89b2758c192c35068b07766a6830433bfbdc1f44 ] The mutex for the regulator_dev must be controlled by the caller of the regulator_notifier_call_chain(), as described in the comment for that function. Failure to mutex lock and unlock surrounding the notifier call results in a kernel WARN_ON_ONCE() which will dump a backtrace for the regulator_notifier_call_chain() when that function call is first made. The mutex can be controlled using the regulator_lock/unlock() API. Fixes: b59320cc5a5e ("regulator: lp8755: new driver for LP8755") Suggested-by: Adam Thomson Signed-off-by: Steve Twiss Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/regulator/lp8755.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/regulator/lp8755.c b/drivers/regulator/lp8755.c index 14fd388071349..2e16a6ab491d6 100644 --- a/drivers/regulator/lp8755.c +++ b/drivers/regulator/lp8755.c @@ -372,10 +372,13 @@ static irqreturn_t lp8755_irq_handler(int irq, void *data) for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++) if ((flag0 & (0x4 << icnt)) && (pchip->irqmask & (0x04 << icnt)) - && (pchip->rdev[icnt] != NULL)) + && (pchip->rdev[icnt] != NULL)) { + regulator_lock(pchip->rdev[icnt]); regulator_notifier_call_chain(pchip->rdev[icnt], LP8755_EVENT_PWR_FAULT, NULL); + regulator_unlock(pchip->rdev[icnt]); + } /* read flag1 register */ ret = lp8755_read(pchip, 0x0E, &flag1); @@ -389,18 +392,24 @@ static irqreturn_t lp8755_irq_handler(int irq, void *data) /* send OCP event to all regulator devices */ if ((flag1 & 0x01) && (pchip->irqmask & 0x01)) for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++) - if (pchip->rdev[icnt] != NULL) + if (pchip->rdev[icnt] != NULL) { + regulator_lock(pchip->rdev[icnt]); regulator_notifier_call_chain(pchip->rdev[icnt], LP8755_EVENT_OCP, NULL); + regulator_unlock(pchip->rdev[icnt]); + } /* send OVP event to all regulator devices */ if ((flag1 & 0x02) && (pchip->irqmask & 0x02)) for (icnt = 0; icnt < LP8755_BUCK_MAX; icnt++) - if (pchip->rdev[icnt] != NULL) + if (pchip->rdev[icnt] != NULL) { + regulator_lock(pchip->rdev[icnt]); regulator_notifier_call_chain(pchip->rdev[icnt], LP8755_EVENT_OVP, NULL); + regulator_unlock(pchip->rdev[icnt]); + } return IRQ_HANDLED; err_i2c: -- 2.20.1