@@ -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:
This is a note to let you know that I have just added a patch titled dell-laptop: Fix allocating & freeing SMI buffer page to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt15. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 558f925a35836b0294ec3117b7036c6476eccdf3 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali.rohar@gmail.com> Date: Tue, 23 Jun 2015 10:11:19 +0200 Subject: dell-laptop: Fix allocating & freeing SMI buffer page MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 <pali.rohar@gmail.com> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/platform/x86/dell-laptop.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-)