From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f43.google.com (mail-pa0-f43.google.com [209.85.220.43]) by kanga.kvack.org (Postfix) with ESMTP id 0A2566B0032 for ; Mon, 22 Jun 2015 15:04:01 -0400 (EDT) Received: by paceq1 with SMTP id eq1so115231789pac.3 for ; Mon, 22 Jun 2015 12:04:00 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [2001:1868:205::9]) by mx.google.com with ESMTPS id a5si30853565pbu.40.2015.06.22.12.03.59 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 22 Jun 2015 12:03:59 -0700 (PDT) Date: Mon, 22 Jun 2015 12:04:00 -0700 From: Darren Hart Subject: Re: [PATCH 3/4] dell-laptop: Fix allocating & freeing SMI buffer page Message-ID: <20150622190400.GD58421@vmdeb7> References: <1434875967-13370-1-git-send-email-pali.rohar@gmail.com> <1434876063-13460-1-git-send-email-pali.rohar@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1434876063-13460-1-git-send-email-pali.rohar@gmail.com> Sender: owner-linux-mm@kvack.org List-ID: To: Pali =?iso-8859-1?Q?Roh=E1r?= Cc: Matthew Garrett , Michal Hocko , platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org On Sun, Jun 21, 2015 at 10:41:03AM +0200, Pali Rohar wrote: > 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 Rohar Looks good - please resend with Cc to stable - that's the simplest path to inclusion in stable. > --- > 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 > > -- Darren Hart Intel Open Source Technology Center -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org