ACPICA: FADT: Remove extraneous warning for very large GPE registers

This change removes a size mismatch warning if the legacy
length field for a GPE register set is larger than the 64-bit
GAS structure can accomodate. GPE register sets can be larger
than the 255 bit limitation of the GAS structure. Linn Crosetto
(linn@hp.com).

Signed-off-by: Linn Crosetto <linn@hp.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/tbfadt.c b/drivers/acpi/acpica/tbfadt.c
index 74181bf181ec..33b00d22300a 100644
--- a/drivers/acpi/acpica/tbfadt.c
+++ b/drivers/acpi/acpica/tbfadt.c
@@ -559,8 +559,12 @@ static void acpi_tb_validate_fadt(void)
                 /*
                  * For each extended field, check for length mismatch between the
                  * legacy length field and the corresponding 64-bit X length field.
+                 * Note: If the legacy length field is > 0xFF bits, ignore this
+                 * check. (GPE registers can be larger than the 64-bit GAS structure
+                 * can accomodate, 0xFF bits).
                  */
                 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",