[PATCH] acpi: remove length check for large registers

[Linn Crosetto <linn@hp.com>]

The legacy bit width field in the Generic Address Structure is 1 byte,
limiting the reportable register width to 255 bits. Larger registers
will cause a length mismatch warning to be printed in
acpi_tb_validate_fadt().

To avoid the warning, disable the length mismatch check for registers
larger than 255 bits.

Signed-off-by: Linn Crosetto <linn@hp.com>
---
 drivers/acpi/acpica/tbfadt.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/acpi/acpica/tbfadt.c b/drivers/acpi/acpica/tbfadt.c
index 74181bf..e87abcd 100644
--- a/drivers/acpi/acpica/tbfadt.c
+++ b/drivers/acpi/acpica/tbfadt.c
@@ -561,6 +561,7 @@ static void acpi_tb_validate_fadt(void)
 		 * legacy length field and the corresponding 64-bit X length field.
 		 */
 		if (address64->address &&
+		    ACPI_MUL_8(length) <= ACPI_UINT8_MAX &&
 		    (address64->bit_width != ACPI_MUL_8(length))) {
 			ACPI_BIOS_WARNING((AE_INFO,
 					   "32/64X length mismatch in FADT/%s: %u/%u",
-- 
1.7.11.3