From patchwork Tue Sep 1 15:10:37 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: 264701 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=-10.0 required=3.0 tests=BAYES_00,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 5D705C433E6 for ; Tue, 1 Sep 2020 15:44:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 28DD6208CA for ; Tue, 1 Sep 2020 15:44:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598975051; bh=RUya4KzYZ3Kazt/S7V1kovWUojhiqJnuKTJaHfXwtTo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=s6ILGQniB4TV8h0A/r6CfrThfnmNI1MjSxWvu5GYqynQNdSzZZAdq3QNQoVcDZeRS K6WA/LTPxRX2SVcOhafl5ONFzZXLFtkzW9fXIwtQhdPFFL3qLUx7FQR5Dj2yqxwFsJ Qby+fRxtlcMIKGfyJ8a8R8iRdb6wvwQ+5UNMtC70= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731772AbgIAPoK (ORCPT ); Tue, 1 Sep 2020 11:44:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:59062 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731770AbgIAPoH (ORCPT ); Tue, 1 Sep 2020 11:44:07 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 4BDA4206EB; Tue, 1 Sep 2020 15:44:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598975046; bh=RUya4KzYZ3Kazt/S7V1kovWUojhiqJnuKTJaHfXwtTo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uIzfts5eZjtdhlTVDsEZq+4RIxvwOlleSypX2nu1cuFOerI0kBJAg4qD89npEBDvW BeqBkYY/wL4PLD0WJjcF5uAB0gvbMVaDcUs//LEtOGjfQp9VU0l72Ndz5wHKWARRH2 BNH00N5OQwU4I8pkqs/O6B9m0VJYhogcDZODCVBk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lukas Wunner , Aleksey Makarov , Peter Hurley , Russell King , Christopher Covington Subject: [PATCH 5.8 181/255] serial: pl011: Fix oops on -EPROBE_DEFER Date: Tue, 1 Sep 2020 17:10:37 +0200 Message-Id: <20200901151009.358712036@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200901151000.800754757@linuxfoundation.org> References: <20200901151000.800754757@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 27afac93e3bd7fa89749cf11da5d86ac9cde4dba upstream. If probing of a pl011 gets deferred until after free_initmem(), an oops ensues because pl011_console_match() is called which has been freed. Fix by removing the __init attribute from the function and those it calls. Commit 10879ae5f12e ("serial: pl011: add console matching function") introduced pl011_console_match() not just for early consoles but regular preferred consoles, such as those added by acpi_parse_spcr(). Regular consoles may be registered after free_initmem() for various reasons, one being deferred probing, another being dynamic enablement of serial ports using a DeviceTree overlay. Thus, pl011_console_match() must not be declared __init and the functions it calls mustn't either. Stack trace for posterity: Unable to handle kernel paging request at virtual address 80c38b58 Internal error: Oops: 8000000d [#1] PREEMPT SMP ARM PC is at pl011_console_match+0x0/0xfc LR is at register_console+0x150/0x468 [<80187004>] (register_console) [<805a8184>] (uart_add_one_port) [<805b2b68>] (pl011_register_port) [<805b3ce4>] (pl011_probe) [<80569214>] (amba_probe) [<805ca088>] (really_probe) [<805ca2ec>] (driver_probe_device) [<805ca5b0>] (__device_attach_driver) [<805c8060>] (bus_for_each_drv) [<805c9dfc>] (__device_attach) [<805ca630>] (device_initial_probe) [<805c90a8>] (bus_probe_device) [<805c95a8>] (deferred_probe_work_func) Fixes: 10879ae5f12e ("serial: pl011: add console matching function") Signed-off-by: Lukas Wunner Cc: stable@vger.kernel.org # v4.10+ Cc: Aleksey Makarov Cc: Peter Hurley Cc: Russell King Cc: Christopher Covington Link: https://lore.kernel.org/r/f827ff09da55b8c57d316a1b008a137677b58921.1597315557.git.lukas@wunner.de Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/amba-pl011.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -2241,9 +2241,8 @@ pl011_console_write(struct console *co, clk_disable(uap->clk); } -static void __init -pl011_console_get_options(struct uart_amba_port *uap, int *baud, - int *parity, int *bits) +static void pl011_console_get_options(struct uart_amba_port *uap, int *baud, + int *parity, int *bits) { if (pl011_read(uap, REG_CR) & UART01x_CR_UARTEN) { unsigned int lcr_h, ibrd, fbrd; @@ -2276,7 +2275,7 @@ pl011_console_get_options(struct uart_am } } -static int __init pl011_console_setup(struct console *co, char *options) +static int pl011_console_setup(struct console *co, char *options) { struct uart_amba_port *uap; int baud = 38400; @@ -2344,8 +2343,8 @@ static int __init pl011_console_setup(st * * Returns 0 if console matches; otherwise non-zero to use default matching */ -static int __init pl011_console_match(struct console *co, char *name, int idx, - char *options) +static int pl011_console_match(struct console *co, char *name, int idx, + char *options) { unsigned char iotype; resource_size_t addr;