Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932866AbbFUIlb (ORCPT ); Sun, 21 Jun 2015 04:41:31 -0400 Received: from mail-wi0-f181.google.com ([209.85.212.181]:33700 "EHLO mail-wi0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753507AbbFUIlX (ORCPT ); Sun, 21 Jun 2015 04:41:23 -0400 From: =?UTF-8?q?Pali=20Roh=C3=A1r?= To: Darren Hart , Matthew Garrett , Michal Hocko Cc: platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, =?UTF-8?q?Pali=20Roh=C3=A1r?= Subject: [PATCH 3/4] dell-laptop: Fix allocating & freeing SMI buffer page Date: Sun, 21 Jun 2015 10:41:03 +0200 Message-Id: <1434876063-13460-1-git-send-email-pali.rohar@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1434875967-13370-1-git-send-email-pali.rohar@gmail.com> References: <1434875967-13370-1-git-send-email-pali.rohar@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1785 Lines: 55 This commit fix kernel crash when probing for rfkill devices in dell-laptop driver failed. Function free_page() was incorrectly used on struct page * instead of virtual address of SMI buffer. This commit also simplify allocating page for SMI buffer by using __get_free_page() function instead of sequential call of functions alloc_page() and page_address(). Signed-off-by: Pali Rohár --- drivers/platform/x86/dell-laptop.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c index aaef335..0a91599 100644 --- a/drivers/platform/x86/dell-laptop.c +++ b/drivers/platform/x86/dell-laptop.c @@ -306,7 +306,6 @@ static const struct dmi_system_id dell_quirks[] __initconst = { }; static struct calling_interface_buffer *buffer; -static struct page *bufferpage; static DEFINE_MUTEX(buffer_mutex); static int hwswitch_state; @@ -2097,12 +2096,11 @@ static int __init dell_init(void) * Allocate buffer below 4GB for SMI data--only 32-bit physical addr * is passed to SMI handler. */ - bufferpage = alloc_page(GFP_KERNEL | GFP_DMA32); - if (!bufferpage) { + buffer = (void *)__get_free_page(GFP_KERNEL | GFP_DMA32); + if (!buffer) { ret = -ENOMEM; goto fail_buffer; } - buffer = page_address(bufferpage); ret = dell_setup_rfkill(); @@ -2165,7 +2163,7 @@ static int __init dell_init(void) fail_backlight: dell_cleanup_rfkill(); fail_rfkill: - free_page((unsigned long)bufferpage); + free_page((unsigned long)buffer); fail_buffer: platform_device_del(platform_device); fail_platform_device2: -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in Please read the FAQ at http://www.tux.org/lkml/