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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC959C3527A for ; Wed, 6 Apr 2022 01:06:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1839678AbiDFBFT (ORCPT ); Tue, 5 Apr 2022 21:05:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44586 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240392AbiDEKcj (ORCPT ); Tue, 5 Apr 2022 06:32:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA7A9DE906; Tue, 5 Apr 2022 03:18:36 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 59CDE61777; Tue, 5 Apr 2022 10:18:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4228CC385A1; Tue, 5 Apr 2022 10:18:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649153915; bh=9PEFQguw30U1gpsVR7cU8RY0vR6P0NTVaLm1k7N31mQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SEPSUYsy+gRZzA7LJ/UWk6NdGeOPsfpe5HAViPJDRgMT47p5vJJeXGtsGnBr7070v aVZXYPGWjC6r0rIhOpb3lhEk59BGAzo4s5S2UTy7sdayFrDss5YvYoq9Ah3HneGZuT 6UPNd0N+1C5aTYc70h/Io5hkdBKpUR8Fn8e+JEoM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Qing Wang , Andy Shevchenko , Sasha Levin Subject: [PATCH 5.10 393/599] serial: 8250_lpss: Balance reference count for PCI DMA device Date: Tue, 5 Apr 2022 09:31:27 +0200 Message-Id: <20220405070310.526505829@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070258.802373272@linuxfoundation.org> References: <20220405070258.802373272@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andy Shevchenko [ Upstream commit 5318f70da7e82649d794fc27d8a127c22aa3566e ] The pci_get_slot() increases its reference count, the caller must decrement the reference count by calling pci_dev_put(). Fixes: 9a1870ce812e ("serial: 8250: don't use slave_id of dma_slave_config") Depends-on: a13e19cf3dc1 ("serial: 8250_lpss: split LPSS driver to separate module") Reported-by: Qing Wang Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20220223151240.70248-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/8250/8250_lpss.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-) diff --git a/drivers/tty/serial/8250/8250_lpss.c b/drivers/tty/serial/8250/8250_lpss.c index 4dee8a9e0c95..dfb730b7ea2a 100644 --- a/drivers/tty/serial/8250/8250_lpss.c +++ b/drivers/tty/serial/8250/8250_lpss.c @@ -121,8 +121,7 @@ static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port) { struct dw_dma_slave *param = &lpss->dma_param; struct pci_dev *pdev = to_pci_dev(port->dev); - unsigned int dma_devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0); - struct pci_dev *dma_dev = pci_get_slot(pdev->bus, dma_devfn); + struct pci_dev *dma_dev; switch (pdev->device) { case PCI_DEVICE_ID_INTEL_BYT_UART1: @@ -141,6 +140,8 @@ static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port) return -EINVAL; } + dma_dev = pci_get_slot(pdev->bus, PCI_DEVFN(PCI_SLOT(pdev->devfn), 0)); + param->dma_dev = &dma_dev->dev; param->m_master = 0; param->p_master = 1; @@ -156,11 +157,26 @@ static int byt_serial_setup(struct lpss8250 *lpss, struct uart_port *port) return 0; } +static void byt_serial_exit(struct lpss8250 *lpss) +{ + struct dw_dma_slave *param = &lpss->dma_param; + + /* Paired with pci_get_slot() in the byt_serial_setup() above */ + put_device(param->dma_dev); +} + static int ehl_serial_setup(struct lpss8250 *lpss, struct uart_port *port) { return 0; } +static void ehl_serial_exit(struct lpss8250 *lpss) +{ + struct uart_8250_port *up = serial8250_get_port(lpss->data.line); + + up->dma = NULL; +} + #ifdef CONFIG_SERIAL_8250_DMA static const struct dw_dma_platform_data qrk_serial_dma_pdata = { .nr_channels = 2, @@ -335,8 +351,7 @@ static int lpss8250_probe(struct pci_dev *pdev, const struct pci_device_id *id) return 0; err_exit: - if (lpss->board->exit) - lpss->board->exit(lpss); + lpss->board->exit(lpss); pci_free_irq_vectors(pdev); return ret; } @@ -347,8 +362,7 @@ static void lpss8250_remove(struct pci_dev *pdev) serial8250_unregister_port(lpss->data.line); - if (lpss->board->exit) - lpss->board->exit(lpss); + lpss->board->exit(lpss); pci_free_irq_vectors(pdev); } @@ -356,12 +370,14 @@ static const struct lpss8250_board byt_board = { .freq = 100000000, .base_baud = 2764800, .setup = byt_serial_setup, + .exit = byt_serial_exit, }; static const struct lpss8250_board ehl_board = { .freq = 200000000, .base_baud = 12500000, .setup = ehl_serial_setup, + .exit = ehl_serial_exit, }; static const struct lpss8250_board qrk_board = { -- 2.34.1