From patchwork Tue Jun 16 15:34:35 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 224462 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=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 155A8C433E1 for ; Tue, 16 Jun 2020 15:52:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EFAA6215A4 for ; Tue, 16 Jun 2020 15:52:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592322747; bh=wtNPFtGFotQHpz0yNm/HnBPZw/CMNGj4GaPvoRT6xos=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=cB7AJV9+7cXRvoCDXuyt1U8ceiLsxd/wrZ3DILufIe4iQ08M5ogzHR7ZHku0WdVWu PS11KFQVFBn9+Od3QHNbNMbyjxGInEJjuPefaGZsqfUT6bo+Yqtzss0GNJGCsrgZz6 KBWc7q0WMTgLpQSsyB2NxC8LmnzkDF1aEvrUNBlg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731713AbgFPPwZ (ORCPT ); Tue, 16 Jun 2020 11:52:25 -0400 Received: from mail.kernel.org ([198.145.29.99]:49654 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732763AbgFPPwV (ORCPT ); Tue, 16 Jun 2020 11:52:21 -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 329C721556; Tue, 16 Jun 2020 15:52:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592322740; bh=wtNPFtGFotQHpz0yNm/HnBPZw/CMNGj4GaPvoRT6xos=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wuwHCQF1ji5hiPuo5WWuo9MhrVKdBqWkWK/R6dEw8QZT2RkYyXx7QxTgHOCLKHm5N Ud7EG+oKlmOIsLdeclr+gw3UhwU9auI6RgvmXMWjJgZ1dhw0tDZgo0ZWeKXnHSyybT tiqtyC7CzHW14g8yYh6xxMQFKX9LDfGwLzgh6/Ls= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lukas Wunner , Andy Shevchenko , Baruch Siach , Mark Brown Subject: [PATCH 5.6 085/161] spi: dw: Fix controller unregister order Date: Tue, 16 Jun 2020 17:34:35 +0200 Message-Id: <20200616153110.419388361@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200616153106.402291280@linuxfoundation.org> References: <20200616153106.402291280@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Lukas Wunner commit ca8b19d61e3fce5d2d7790cde27a0b57bcb3f341 upstream. The Designware SPI driver uses devm_spi_register_controller() on bind. As a consequence, on unbind, __device_release_driver() first invokes dw_spi_remove_host() before unregistering the SPI controller via devres_release_all(). This order is incorrect: dw_spi_remove_host() shuts down 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 dw_spi_remove_host(), 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. Fixes: 04f421e7b0b1 ("spi: dw: use managed resources") Signed-off-by: Lukas Wunner Reviewed-by: Andy Shevchenko Cc: stable@vger.kernel.org # v3.14+ Cc: Baruch Siach Link: https://lore.kernel.org/r/3fff8cb8ae44a9893840d0688be15bb88c090a14.1590408496.git.lukas@wunner.de Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spi-dw.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/spi/spi-dw.c +++ b/drivers/spi/spi-dw.c @@ -534,7 +534,7 @@ int dw_spi_add_host(struct device *dev, } } - ret = devm_spi_register_controller(dev, master); + ret = spi_register_controller(master); if (ret) { dev_err(&master->dev, "problem registering spi master\n"); goto err_dma_exit; @@ -558,6 +558,8 @@ void dw_spi_remove_host(struct dw_spi *d { dw_spi_debugfs_remove(dws); + spi_unregister_controller(dws->master); + if (dws->dma_ops && dws->dma_ops->dma_exit) dws->dma_ops->dma_exit(dws);