Messages in this thread Patch in this message | | | From | Kamal Mostafa <> | Subject | [PATCH 3.13.y-ckt 089/132] dell-laptop: Fix allocating & freeing SMI buffer page | Date | Wed, 22 Jul 2015 19:00:07 -0700 |
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3.13.11-ckt24 -stable review patch. If anyone has any objections, please let me know.
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From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali.rohar@gmail.com>
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: Kamal Mostafa <kamal@canonical.com> --- 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 c608b1d..eb1b398 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; @@ -814,12 +813,11 @@ 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(); @@ -888,7 +886,7 @@ fail_backlight: fail_filter: 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: -- 1.9.1
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