Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753503AbbGOJOu (ORCPT ); Wed, 15 Jul 2015 05:14:50 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:45323 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753454AbbGOJOp (ORCPT ); Wed, 15 Jul 2015 05:14:45 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: =?UTF-8?q?Pali=20Roh=C3=A1r?= , Darren Hart , Luis Henriques Subject: [PATCH 3.16.y-ckt 112/185] dell-laptop: Fix allocating & freeing SMI buffer page Date: Wed, 15 Jul 2015 10:11:47 +0100 Message-Id: <1436951580-15977-113-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1436951580-15977-1-git-send-email-luis.henriques@canonical.com> References: <1436951580-15977-1-git-send-email-luis.henriques@canonical.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2266 Lines: 65 3.16.7-ckt15 -stable review patch. If anyone has any objections, please let me know. ------------------ From: =?UTF-8?q?Pali=20Roh=C3=A1r?= commit b8830a4e71b15d0364ac8e6c55301eea73f211da upstream. 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 Acked-by: Michal Hocko Signed-off-by: Darren Hart Signed-off-by: Luis Henriques --- 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 fed4111ac31a..1beb232ef03b 100644 --- a/drivers/platform/x86/dell-laptop.c +++ b/drivers/platform/x86/dell-laptop.c @@ -272,7 +272,6 @@ static struct dmi_system_id dell_quirks[] = { }; static struct calling_interface_buffer *buffer; -static struct page *bufferpage; static DEFINE_MUTEX(buffer_mutex); static int hwswitch_state; @@ -825,12 +824,11 @@ 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(); @@ -892,7 +890,7 @@ fail_backlight: cancel_delayed_work_sync(&dell_rfkill_work); 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: -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/