From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: [PATCH 1/7] ACPI Hibernation: Use ACPI hardware signature Date: Tue, 20 May 2008 01:31:33 +0200 Message-ID: <200805200131.33913.rjw@sisk.pl> References: <200805200129.19904.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Return-path: Received: from ogre.sisk.pl ([217.79.144.158]:40095 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755848AbYESXmN (ORCPT ); Mon, 19 May 2008 19:42:13 -0400 In-Reply-To: <200805200129.19904.rjw@sisk.pl> Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Len Brown Cc: ACPI Devel Maling List , Pavel Machek , pm list , Shaohua Li From: Shaohua Li ACPI defines a hardware signature. BIOS calculates the signature according to hardware configure, if hardware changes, the signature will change, in this case, S4 resume should fail. Signed-off-by: Shaohua Li Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki --- Documentation/kernel-parameters.txt | 5 +++++ drivers/acpi/sleep/main.c | 24 ++++++++++++++++++++++++ 2 files changed, 29 insertions(+) Index: linux-2.6/drivers/acpi/sleep/main.c =================================================================== --- linux-2.6.orig/drivers/acpi/sleep/main.c +++ linux-2.6/drivers/acpi/sleep/main.c @@ -255,6 +255,17 @@ static struct dmi_system_id __initdata a #endif /* CONFIG_SUSPEND */ #ifdef CONFIG_HIBERNATION +static unsigned long s4_hardware_signature; +static struct acpi_table_facs *facs; +static bool nosigcheck; + +static int __init acpi_s4_nosigcheck(char *str) +{ + nosigcheck = true; + return 1; +} +__setup("acpi_s4_nosigcheck", acpi_s4_nosigcheck); + static int acpi_hibernation_begin(void) { acpi_target_sleep_state = ACPI_STATE_S4; @@ -301,6 +312,12 @@ static void acpi_hibernation_leave(void) acpi_enable(); /* Reprogram control registers and execute _BFS */ acpi_leave_sleep_state_prep(ACPI_STATE_S4); + /* Check the hardware signature */ + if (facs && s4_hardware_signature != facs->hardware_signature) { + printk(KERN_EMERG "ACPI: Hardware changed while hibernated, " + "cannot resume!\n"); + panic("ACPI S4 hardware signature mismatch"); + } } static void acpi_hibernation_finish(void) @@ -501,6 +518,13 @@ int __init acpi_sleep_init(void) hibernation_set_ops(&acpi_hibernation_ops); sleep_states[ACPI_STATE_S4] = 1; printk(" S4"); + if (!nosigcheck) { + acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS, + (struct acpi_table_header **)&facs); + if (facs) + s4_hardware_signature = + facs->hardware_signature; + } } #endif status = acpi_get_sleep_type_data(ACPI_STATE_S5, &type_a, &type_b); Index: linux-2.6/Documentation/kernel-parameters.txt =================================================================== --- linux-2.6.orig/Documentation/kernel-parameters.txt +++ linux-2.6/Documentation/kernel-parameters.txt @@ -152,6 +152,11 @@ and is between 256 and 4096 characters. s3_beep is for debugging; it makes the PC's speaker beep as soon as the kernel's real-mode entry point is called. + acpi_s4_nosigcheck [HW,ACPI] S4 hardware signature + ACPI will ignore the S4 hardware signature + default: The hardware signature is checked during + resume from S4. + acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode Format: { level | edge | high | low }