[patch 24/56] ACPI: disable ACPI cleanly when bad RSDP found

Greg KH
2009-02-11T00:36:27Z

[-- Attachment #1: acpi-disable-acpi-cleanly-when-bad-rsdp-found.patch --]
[-- Type: text/plain, Size: 1280 bytes --]

2.6.27-stable review patch. If anyone has any objections, please let us know.
------------------

From: Len Brown <len.brown@intel.com>

commit 9e3a9d1ed8cc8db93e5c53e9a5b09065bd95de8b upstream.

When ACPI is disabled in the BIOS of this VIA C3 box,
it invalidates the RSDP, which Linux notices:

ACPI Error (tbxfroot-0218): A valid RSDP was not found [20080926]

Bug Linux neglected to disable ACPI at that stage,
and later scribbled on smp_found_config:

ACPI: No APIC-table, disabling MPS

But this box doesn't run well in legacy PIC mode,
it needed IOAPIC mode to perform correctly:

http://lkml.org/lkml/2009/2/5/39

So exit ACPI mode cleanly when we first detect
that it is hopeless.

Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/acpi/tables.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

--- a/drivers/acpi/tables.c
+++ b/drivers/acpi/tables.c
@@ -293,7 +293,12 @@ static void __init check_multiple_madt(v

int __init acpi_table_init(void)
{
- acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
+ acpi_status status;
+
+ status = acpi_initialize_tables(initial_tables, ACPI_MAX_TABLES, 0);
+ if (ACPI_FAILURE(status))
+ return 1;
+
check_multiple_madt();
return 0;
}