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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 C0122C433E0 for ; Tue, 16 Jun 2020 15:39:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A2646214DB for ; Tue, 16 Jun 2020 15:39:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592321941; bh=ROD4OS853yfOamcyXBqlH9ryzTfV4idnYgurUQsATrE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=uzxgsRsimtXL1rZ333Ril2AwZab6MaN7YNBtW6vSBp8DMV9pCW0mkEZfwat4PBwj4 EvboO7k86uyPXYCSHp+OG5NynUEd4GJ1iQ3CuEOuLg0RsAyPX1UrQ6Re7l/Dpg5WUG E8ez+HYHJ1dNVerHi7L6Y0De5y8VVjykL36EDN+s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730822AbgFPPi7 (ORCPT ); Tue, 16 Jun 2020 11:38:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:51744 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729966AbgFPPix (ORCPT ); Tue, 16 Jun 2020 11:38:53 -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 5AFEC20B1F; Tue, 16 Jun 2020 15:38:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592321932; bh=ROD4OS853yfOamcyXBqlH9ryzTfV4idnYgurUQsATrE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VKpRu1SmHHvcWAL9iS/gYG5dexsoLQENAg0+b3AyCAbfNPadDoRGjGBB4ehuqBLmg DRdjfUJw1OLOxPoGSuuTRDlGCMQ51of3DajiPZ9dPY+IIf81FcmXVrxHx2Dtendlxb eJCM+MC2Il6+XLIRawUXwLTOOc32FxhtlwNEJtD4= 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 Subject: [PATCH 5.4 071/134] spi: pxa2xx: Fix controller unregister order Date: Tue, 16 Jun 2020 17:34:15 +0200 Message-Id: <20200616153104.177737040@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200616153100.633279950@linuxfoundation.org> References: <20200616153100.633279950@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 commit 32e5b57232c0411e7dea96625c415510430ac079 upstream. 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: Greg Kroah-Hartman --- drivers/spi/spi-pxa2xx.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -1880,7 +1880,7 @@ static int pxa2xx_spi_probe(struct platf /* Register with the SPI framework */ platform_set_drvdata(pdev, drv_data); - status = devm_spi_register_controller(&pdev->dev, controller); + status = spi_register_controller(controller); if (status != 0) { dev_err(&pdev->dev, "problem registering spi controller\n"); goto out_error_pm_runtime_enabled; @@ -1916,6 +1916,8 @@ static int pxa2xx_spi_remove(struct plat pm_runtime_get_sync(&pdev->dev); + spi_unregister_controller(drv_data->controller); + /* Disable the SSP at the peripheral and SOC level */ pxa2xx_spi_write(drv_data, SSCR0, 0); clk_disable_unprepare(ssp->clk);