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 22212C433E2 for ; Fri, 19 Jun 2020 16:51:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 00D34206B7 for ; Fri, 19 Jun 2020 16:51:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592585485; bh=jJAuHfsEWXZKFASwgw4Xo+bzhzlKTDQqmMhdwufUCYE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=T2QN0WON5mAc+BOuPcsapwT9pkf8MtK4NIKVgcNOCAbH66keSd+DiZaIdLdpO3K+p +8No4ZHFO6KQrL3p4uJnla7fXmLPTFQlyq2C02PpXVL/415DAJOvQn9RYrmZvKt8Sa yIyNEaMSarrViJXJ4vnCWzMAb1aivGataeppXa9s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387833AbgFSOiL (ORCPT ); Fri, 19 Jun 2020 10:38:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:55136 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733291AbgFSOiJ (ORCPT ); Fri, 19 Jun 2020 10:38:09 -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 1EA2820CC7; Fri, 19 Jun 2020 14:38:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592577488; bh=jJAuHfsEWXZKFASwgw4Xo+bzhzlKTDQqmMhdwufUCYE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IIghxc5eM0y1e9LKWf/HoEBVt4EkOl49skwXmUD1JWgYph+KONKdYEMpRVU6Wvc7k KV1ZhY00XTrYGI+TstYi/Y7DDj19j8O2y7HjMyXAGWUI8o7AwRvznHhsG0IqFwTdue QMUTPPXXjUF6cVA9S7spMkbozWGF7pcoknFi8EuE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lukas Wunner , Mark Brown , Sasha Levin Subject: [PATCH 4.4 031/101] spi: bcm2835: Fix controller unregister order Date: Fri, 19 Jun 2020 16:32:20 +0200 Message-Id: <20200619141615.722934389@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 [ Upstream commit 9dd277ff92d06f6aa95b39936ad83981d781f49b ] The BCM2835 SPI driver uses devm_spi_register_controller() on bind. As a consequence, on unbind, __device_release_driver() first invokes bcm2835_spi_remove() before unregistering the SPI controller via devres_release_all(). This order is incorrect: bcm2835_spi_remove() tears down the DMA channels and 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_controller() 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_controller(). Note that the struct spi_controller as well as the driver-private data are not freed until after bcm2835_spi_remove() has finished, so accessing them is safe. Fixes: 247263dba208 ("spi: bcm2835: use devm_spi_register_master()") Signed-off-by: Lukas Wunner Cc: stable@vger.kernel.org # v3.13+ Link: https://lore.kernel.org/r/2397dd70cdbe95e0bc4da2b9fca0f31cb94e5aed.1589557526.git.lukas@wunner.de Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-bcm2835.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index 25daebd6f410..27680b336454 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -798,7 +798,7 @@ static int bcm2835_spi_probe(struct platform_device *pdev) 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; @@ -818,6 +818,8 @@ static int bcm2835_spi_remove(struct platform_device *pdev) struct spi_master *master = platform_get_drvdata(pdev); struct bcm2835_spi *bs = spi_master_get_devdata(master); + spi_unregister_master(master); + /* Clear FIFOs, and disable the HW block */ bcm2835_wr(bs, BCM2835_SPI_CS, BCM2835_SPI_CS_CLEAR_RX | BCM2835_SPI_CS_CLEAR_TX); -- 2.25.1