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 96900C433E1 for ; Fri, 19 Jun 2020 16:55:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 74E9D20786 for ; Fri, 19 Jun 2020 16:55:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592585700; bh=TJ37aGeRnF5SOqXAIKJ5XavM4oJ4fEAX1NdGoYH1k6g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=FerSJ/MuQ3yeyz4nC1Ozvd4fGhSDgxYQz5YPb9fXPP00OQ49r3r27e9c20vBTQ212 qpDFSah6AY62ANc1uaKRbA3E9sPnxb3RWwckPiaobTriZ7HkKlHY/QMGi65IVZ757T VeB9Mrj6YgUt+vLZZ1z0FeDSNw4Drra3BO008Qpw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387465AbgFSOgI (ORCPT ); Fri, 19 Jun 2020 10:36:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:52376 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387446AbgFSOgC (ORCPT ); Fri, 19 Jun 2020 10:36:02 -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 C1DB921548; Fri, 19 Jun 2020 14:36:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592577362; bh=TJ37aGeRnF5SOqXAIKJ5XavM4oJ4fEAX1NdGoYH1k6g=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ffv+Xthkpr9+nrxoI7cQQIxcNIKulXWz6qpi+Td970EMJtxTFCq07lQ7Tj/fEOtTc XANjTGCmUNRgFaidHyWDNmKiNm5P9oKR6mSMLagfVYQmA4OwMEiNY4oxfrXfSc7nEm mWNQOaxJFKs0BEn/OzKyHIOeDHOYJ5PlYoctwtJA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lukas Wunner , Martin Sperl , Mark Brown Subject: [PATCH 4.4 020/101] spi: bcm2835aux: Fix controller unregister order Date: Fri, 19 Jun 2020 16:32:09 +0200 Message-Id: <20200619141615.143856517@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141614.001544111@linuxfoundation.org> References: <20200619141614.001544111@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 From: Lukas Wunner commit b9dd3f6d417258ad0beeb292a1bc74200149f15d upstream. The BCM2835aux SPI driver uses devm_spi_register_master() on bind. As a consequence, on unbind, __device_release_driver() first invokes bcm2835aux_spi_remove() before unregistering the SPI controller via devres_release_all(). This order is incorrect: bcm2835aux_spi_remove() turns off the SPI controller, including its interrupts and clock. The SPI controller is thus no longer usable. When the SPI controller is subsequently unregistered, it unbinds all its slave devices. If their drivers need to access the SPI bus, e.g. to quiesce their interrupts, unbinding will fail. As a rule, devm_spi_register_master() must not be used if the ->remove() hook performs teardown steps which shall be performed after unbinding of slaves. Fix by using the non-devm variant spi_register_master(). Note that the struct spi_master as well as the driver-private data are not freed until after bcm2835aux_spi_remove() has finished, so accessing them is safe. Fixes: 1ea29b39f4c8 ("spi: bcm2835aux: add bcm2835 auxiliary spi device driver") Signed-off-by: Lukas Wunner Cc: stable@vger.kernel.org # v4.4+ Cc: Martin Sperl Link: https://lore.kernel.org/r/32f27f4d8242e4d75f9a53f7e8f1f77483b08669.1589557526.git.lukas@wunner.de Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spi-bcm2835aux.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -457,7 +457,7 @@ static int bcm2835aux_spi_probe(struct p goto out_clk_disable; } - err = devm_spi_register_master(&pdev->dev, master); + err = spi_register_master(master); if (err) { dev_err(&pdev->dev, "could not register SPI master: %d\n", err); goto out_clk_disable; @@ -477,6 +477,8 @@ static int bcm2835aux_spi_remove(struct struct spi_master *master = platform_get_drvdata(pdev); struct bcm2835aux_spi *bs = spi_master_get_devdata(master); + spi_unregister_master(master); + bcm2835aux_spi_reset_hw(bs); /* disable the HW block by releasing the clock */