From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:39366 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754024AbeBWSig (ORCPT ); Fri, 23 Feb 2018 13:38:36 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Luis R. Rodriguez" , Wolfram Sang Subject: [PATCH 4.4 128/193] i2c: remove __init from i2c_register_board_info() Date: Fri, 23 Feb 2018 19:26:01 +0100 Message-Id: <20180223170345.922970960@linuxfoundation.org> In-Reply-To: <20180223170325.997716448@linuxfoundation.org> References: <20180223170325.997716448@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Luis R. Rodriguez commit 5abe9b26847c65a698f38744a52635b287514294 upstream. As of next-20160607 with allyesconfig we get this linker failure: MODPOST vmlinux.o WARNING: vmlinux.o(.text+0x21bc0d): Section mismatch in reference from the function intel_scu_devices_create() to the function .init.text:i2c_register_board_info() This is caused by the fact that intel_scu_devices_create() calls i2c_register_board_info() and intel_scu_devices_create() is not annotated with __init. This typically involves manual code inspection and if one is certain this is correct we would just peg intel_scu_devices_create() with a __ref annotation. In this case this would be wrong though as the intel_scu_devices_create() call is exported, and used in the ipc_probe() on drivers/platform/x86/intel_scu_ipc.c. The issue is that even though builtin_pci_driver(ipc_driver) is used this just exposes the probe routine, which can occur at any point in time if this bus supports hotplug. A race can happen between kernel_init_freeable() that calls the init calls (in this case registeres the intel_scu_ipc.c driver, and later free_initmem(), which would free the i2c_register_board_info(). If a probe happens later in boot i2c_register_board_info() would not be present and we should get a page fault. Signed-off-by: Luis R. Rodriguez [wsa: made function declaration a one-liner] Signed-off-by: Wolfram Sang Signed-off-by: Greg Kroah-Hartman --- drivers/i2c/i2c-boardinfo.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/drivers/i2c/i2c-boardinfo.c +++ b/drivers/i2c/i2c-boardinfo.c @@ -56,9 +56,7 @@ EXPORT_SYMBOL_GPL(__i2c_first_dynamic_bu * The board info passed can safely be __initdata, but be careful of embedded * pointers (for platform_data, functions, etc) since that won't be copied. */ -int __init -i2c_register_board_info(int busnum, - struct i2c_board_info const *info, unsigned len) +int i2c_register_board_info(int busnum, struct i2c_board_info const *info, unsigned len) { int status;