From mboxrd@z Thu Jan 1 00:00:00 1970 From: Len Brown Subject: [stable PATCH 2.6.21] ACPICA: Ignore ACPI table signature for Load() operator Date: Wed, 18 Jun 2008 22:13:00 -0400 (EDT) Message-ID: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: Received: from vms173003pub.verizon.net ([206.46.173.3]:62731 "EHLO vms173003pub.verizon.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751544AbYFSCNT (ORCPT ); Wed, 18 Jun 2008 22:13:19 -0400 Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: stable@kernel.org Cc: linux-acpi@vger.kernel.org, Linux Kernel Mailing List From: Bob Moore upstream bc45b1d39a925b56796bebf8a397a0491489d85c Only "SSDT" is acceptable to the ACPI spec, but tables are seen with OEMx and null sigs. Therefore, signature validation is worthless. Apparently MS ACPI accepts such signatures, ACPICA must be compatible. Without this patch booting with acpi_osi="!Windows 2006" is required for several machines to function properly with cpufreq. http://bugzilla.kernel.org/show_bug.cgi?id=9919 http://bugzilla.kernel.org/show_bug.cgi?id=10383 http://bugzilla.kernel.org/show_bug.cgi?id=10454 https://bugzilla.novell.com/show_bug.cgi?id=396311 Signed-off-by: Bob Moore Signed-off-by: Lin Ming Signed-off-by: Len Brown --- drivers/acpi/tables/tbinstal.c | 25 +++++++------------------ 1 files changed, 7 insertions(+), 18 deletions(-) Index: linux-2.6.21.y/drivers/acpi/tables/tbinstal.c =================================================================== --- linux-2.6.21.y.orig/drivers/acpi/tables/tbinstal.c +++ linux-2.6.21.y/drivers/acpi/tables/tbinstal.c @@ -123,17 +123,13 @@ acpi_tb_add_table(struct acpi_table_desc } } - /* The table must be either an SSDT or a PSDT */ - - if ((!ACPI_COMPARE_NAME(table_desc->pointer->signature, ACPI_SIG_PSDT)) - && - (!ACPI_COMPARE_NAME(table_desc->pointer->signature, ACPI_SIG_SSDT))) - { - ACPI_ERROR((AE_INFO, - "Table has invalid signature [%4.4s], must be SSDT or PSDT", - table_desc->pointer->signature)); - return_ACPI_STATUS(AE_BAD_SIGNATURE); - } + /* + * Originally, we checked the table signature for "SSDT" or "PSDT" here. + * Next, we added support for OEMx tables, signature "OEM". + * Valid tables were encountered with a null signature, so we've just + * given up on validating the signature, since it seems to be a waste + * of code. The original code was removed (05/2008). + */ (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES);