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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 F15ACC433E0 for ; Fri, 19 Jun 2020 16:26:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE44221707 for ; Fri, 19 Jun 2020 16:26:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592583978; bh=NeY9Dw1PfcNqA93uXUO9KWQuMobJOvL1Ii05Q6rjy7g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CWM2zOHqT4QOJGMt1r30IaE7f1hrVEtGUVy8WoeRrtNHtc451qVrHbLUFo7xQOITg g1Mm6D788UT1RpvKN9EBLZe+odj3mLoMzmiBiNzA+KGNc51D/LYmVEOWlgTA8SCLf0 j7HkGMbsfX3YA2tixZXle+pvDWkm4KDav0zlpzAU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390211AbgFSO5R (ORCPT ); Fri, 19 Jun 2020 10:57:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:52112 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390162AbgFSO45 (ORCPT ); Fri, 19 Jun 2020 10:56:57 -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 7AA002158C; Fri, 19 Jun 2020 14:56:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592578617; bh=NeY9Dw1PfcNqA93uXUO9KWQuMobJOvL1Ii05Q6rjy7g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qGn25tm2csQ87H3y4j9MpHD3QzzqwSn4YYagOPmxAUV5viN1r2mGZVzDVTC395Mtl LkV7123VQH2vj/jbSYM59Bk7R0rGUZRipaVte+JrpOdJcQODCi2nH+GDVI8w3vmHkM z76bMWiPtIH/20uRF3MNqBpVCqX598tPDnofwd8M= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lukas Wunner , Andy Shevchenko , Tsuchiya Yuto , Mark Brown , Sasha Levin Subject: [PATCH 4.19 060/267] spi: pxa2xx: Fix controller unregister order Date: Fri, 19 Jun 2020 16:30:45 +0200 Message-Id: <20200619141651.747601511@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141648.840376470@linuxfoundation.org> References: <20200619141648.840376470@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: Lukas Wunner [ Upstream commit 32e5b57232c0411e7dea96625c415510430ac079 ] The PXA2xx SPI driver uses devm_spi_register_controller() on bind. As a consequence, on unbind, __device_release_driver() first invokes pxa2xx_spi_remove() before unregistering the SPI controller via devres_release_all(). This order is incorrect: pxa2xx_spi_remove() disables the chip, rendering the SPI bus inaccessible even though the SPI controller is still registered. When the SPI controller is subsequently unregistered, it unbinds all its slave devices. Because their drivers cannot access the SPI bus, e.g. to quiesce interrupts, the slave devices may be left in an improper state. As a rule, devm_spi_register_controller() must not be used if the ->remove() hook performs teardown steps which shall be performed after unregistering the controller and specifically after unbinding of slaves. Fix by reverting to the non-devm variant of spi_register_controller(). An alternative approach would be to use device-managed functions for all steps in pxa2xx_spi_remove(), e.g. by calling devm_add_action_or_reset() on probe. However that approach would add more LoC to the driver and it wouldn't lend itself as well to backporting to stable. The improper use of devm_spi_register_controller() was introduced in 2013 by commit a807fcd090d6 ("spi: pxa2xx: use devm_spi_register_master()"), but all earlier versions of the driver going back to 2006 were likewise broken because they invoked spi_unregister_master() at the end of pxa2xx_spi_remove(), rather than at the beginning. Fixes: e0c9905e87ac ("[PATCH] SPI: add PXA2xx SSP SPI Driver") Signed-off-by: Lukas Wunner Reviewed-by: Andy Shevchenko Cc: stable@vger.kernel.org # v2.6.17+ Cc: Tsuchiya Yuto Link: https://bugzilla.kernel.org/show_bug.cgi?id=206403#c1 Link: https://lore.kernel.org/r/834c446b1cf3284d2660f1bee1ebe3e737cd02a9.1590408496.git.lukas@wunner.de Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-pxa2xx.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index e4482823d8d7..d6c30bd1583f 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -1739,7 +1739,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) /* Register with the SPI framework */ platform_set_drvdata(pdev, drv_data); - status = devm_spi_register_controller(&pdev->dev, master); + status = spi_register_controller(master); if (status != 0) { dev_err(&pdev->dev, "problem registering spi master\n"); goto out_error_clock_enabled; @@ -1773,6 +1773,8 @@ static int pxa2xx_spi_remove(struct platform_device *pdev) pm_runtime_get_sync(&pdev->dev); + spi_unregister_controller(drv_data->master); + /* Disable the SSP at the peripheral and SOC level */ pxa2xx_spi_write(drv_data, SSCR0, 0); clk_disable_unprepare(ssp->clk); -- 2.25.1