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=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 30A25C433DF for ; Tue, 16 Jun 2020 15:52:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03DB4208D5 for ; Tue, 16 Jun 2020 15:52:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592322771; bh=yJiFaOZloGB2NSKpB3spvtmWAhuXPh/vE7PAJDTvQoQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CnQqoi/cYYYPG+cY7Hr6szVctqfYTr17VhqRtsj4HeF9bMkj6AKZtVjd5qSXZk9DK FpJbz9m81w1zOcL9pO7/OEdqus2mO9PWWICzRNhqxu/6WS3YnhjsIpl7UjH2p3lIxh KaJEUJsveHtFXUJ8AQeSS4Q8luKZuB2b2dPfriq8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730482AbgFPPwt (ORCPT ); Tue, 16 Jun 2020 11:52:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:50042 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732743AbgFPPwe (ORCPT ); Tue, 16 Jun 2020 11:52:34 -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 33F5F21527; Tue, 16 Jun 2020 15:52:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592322753; bh=yJiFaOZloGB2NSKpB3spvtmWAhuXPh/vE7PAJDTvQoQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pG0w+FccbNIQ1h5PL2U9BGYnpXLhPdldGpaDPQQ/WcpGGOuwiCxiAoZgGvMj6xGnU A0F59XEAWKb0ycqNgobPXF5dIbY0lbj021wmUl9o9YDjXZSh05i8Fm8noeRcyJa8Wi Vw9HlEGfPKmZinNXh0u0HYKsN7mLAWnNvOWkKSb4= 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 5.6 090/161] spi: bcm2835aux: Fix controller unregister order Date: Tue, 16 Jun 2020 17:34:40 +0200 Message-Id: <20200616153110.664328301@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 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 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 @@ -569,7 +569,7 @@ 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; @@ -593,6 +593,8 @@ static int bcm2835aux_spi_remove(struct bcm2835aux_debugfs_remove(bs); + spi_unregister_master(master); + bcm2835aux_spi_reset_hw(bs); /* disable the HW block by releasing the clock */