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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F32CC32789 for ; Mon, 22 Aug 2022 13:01:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234756AbiHVNBA (ORCPT ); Mon, 22 Aug 2022 09:01:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234923AbiHVNAe (ORCPT ); Mon, 22 Aug 2022 09:00:34 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A106333E29 for ; Mon, 22 Aug 2022 06:00:33 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 5D4A1B811CF for ; Mon, 22 Aug 2022 13:00:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A3EAFC433C1; Mon, 22 Aug 2022 13:00:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661173231; bh=ctLFXnjsD90gB1NR7gR/mitaX/MBzldzSUtaNNry3E4=; h=Subject:To:Cc:From:Date:From; b=W//Vach3ivGtlenvRLtpEp+6NVSd2esUeEyVgHZLmZMECCWl30VmtxGXG9LHAjTYK 40rbcAvFNU9huIZaJWMXmCyYe1yQM1uWjSROXl93K7Z3fx+UGaraEu267HAPfG91PZ u4qFJZ/8EOLfL1h53asqWgWRlEIgmTz6rpaa4zn8= Subject: FAILED: patch "[PATCH] i2c: imx: Make sure to unregister adapter on remove()" failed to apply to 4.9-stable tree To: u.kleine-koenig@pengutronix.de, o.rempel@pengutronix.de, wsa@kernel.org Cc: From: Date: Mon, 22 Aug 2022 15:00:15 +0200 Message-ID: <1661173215147161@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From d98bdd3a5b50446d8e010be5b04ce81c4eabf728 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Wed, 20 Jul 2022 17:09:33 +0200 Subject: [PATCH] i2c: imx: Make sure to unregister adapter on remove() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If for whatever reasons pm_runtime_resume_and_get() fails and .remove() is exited early, the i2c adapter stays around and the irq still calls its handler, while the driver data and the register mapping go away. So if later the i2c adapter is accessed or the irq triggers this results in havoc accessing freed memory and unmapped registers. So unregister the software resources even if resume failed, and only skip the hardware access in that case. Fixes: 588eb93ea49f ("i2c: imx: add runtime pm support to improve the performance") Signed-off-by: Uwe Kleine-König Acked-by: Oleksij Rempel Signed-off-by: Wolfram Sang diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 78fb1a4274a6..e47fa3465671 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -1572,9 +1572,7 @@ static int i2c_imx_remove(struct platform_device *pdev) struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev); int irq, ret; - ret = pm_runtime_resume_and_get(&pdev->dev); - if (ret < 0) - return ret; + ret = pm_runtime_get_sync(&pdev->dev); hrtimer_cancel(&i2c_imx->slave_timer); @@ -1585,17 +1583,21 @@ static int i2c_imx_remove(struct platform_device *pdev) if (i2c_imx->dma) i2c_imx_dma_free(i2c_imx); - /* setup chip registers to defaults */ - imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR); - imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR); - imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR); - imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR); + if (ret == 0) { + /* setup chip registers to defaults */ + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR); + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR); + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR); + imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR); + clk_disable(i2c_imx->clk); + } clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb); irq = platform_get_irq(pdev, 0); if (irq >= 0) free_irq(irq, i2c_imx); - clk_disable_unprepare(i2c_imx->clk); + + clk_unprepare(i2c_imx->clk); pm_runtime_put_noidle(&pdev->dev); pm_runtime_disable(&pdev->dev);