Please sign in to comment.
ACPICA: Fix regression in FADT revision checks
commit 3e80acd1af40fcd91a200b0416a7616b20c5d647 upstream. commit 64b3db2 (2.6.39), "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. The effect is that acpi_processor_power_init will notice cst_control != 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. Every one of these settings help to avoid this problem: - acpi=off - processor.nocst=1 - maxcpus=1 The 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=42700 https://bugzilla.redhat.com/show_bug.cgi?id=727865 Signed-off-by: Julian Anastasov <firstname.lastname@example.org> Acked-by: Bob Moore <email@example.com> Signed-off-by: Len Brown <firstname.lastname@example.org> Cc: Jonathan Nieder <email@example.com> Cc: Josh Boyer <firstname.lastname@example.org> Signed-off-by: Greg Kroah-Hartman <email@example.com>
- Loading branch information...