From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Boyer Subject: Re: [PATCH 04/76] ACPICA: Fix regression in FADT revision checks Date: Fri, 30 Mar 2012 09:14:53 -0400 Message-ID: References: <09f98a825a821f7a3f1b162f9ed023f37213a63b.1333101989.git.len.brown@intel.com> <1333102459-23750-1-git-send-email-lenb@kernel.org> <3e80acd1af40fcd91a200b0416a7616b20c5d647.1333101989.git.len.brown@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <3e80acd1af40fcd91a200b0416a7616b20c5d647.1333101989.git.len.brown@intel.com> Sender: linux-acpi-owner@vger.kernel.org To: Len Brown Cc: linux-acpi@vger.kernel.org, linux-pm@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Julian Anastasov , Len Brown List-Id: linux-pm@vger.kernel.org On Fri, Mar 30, 2012 at 6:13 AM, Len Brown wrote: > From: Julian Anastasov > > =A0 =A0 =A0 =A0commit 64b3db22c04586997ab4be46dd5a5b99f8a2d390 (2.6.3= 9), > "Remove use of unreliable FADT revision field" causes regression > for old P4 systems because now cst_control and other fields are > not reset to 0. > > =A0 =A0 =A0 =A0The effect is that acpi_processor_power_init will noti= ce > cst_control !=3D 0 and a write to CST_CNT register is performed > that should not happen. As result, the system oopses after the > "No _CST, giving up" message, sometimes in acpi_ns_internalize_name, > sometimes in acpi_ns_get_type, usually at random places. May be > during migration to CPU 1 in acpi_processor_get_throttling. > > =A0 =A0 =A0 =A0Every one of these settings help to avoid this problem= : > =A0- acpi=3Doff > =A0- processor.nocst=3D1 > =A0- maxcpus=3D1 > > =A0 =A0 =A0 =A0The fix is to update acpi_gbl_FADT.header.length after > the original value is used to check for old revisions. > > https://bugzilla.kernel.org/show_bug.cgi?id=3D42700 > https://bugzilla.redhat.com/show_bug.cgi?id=3D727865 > > Signed-off-by: Julian Anastasov > Acked-by: Bob Moore > Signed-off-by: Len Brown This one should go into the stable trees. The bug it fixes causes a number of machines to not boot with anything newer than 2.6.38. josh -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html