[PATCH 4/4] ACPI: Make sure the FADT is at least rev 2 before using the reset register

Matthew Garrett
2011-03-11T21:12:20Z

The reset register was only introduced with version 2 of the FADT, so we
should check that the FADT revision before trusting its contents.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
---
drivers/acpi/reboot.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/drivers/acpi/reboot.c b/drivers/acpi/reboot.c
index 4870aaa..a6c77e8b 100644
--- a/drivers/acpi/reboot.c
+++ b/drivers/acpi/reboot.c
@@ -15,6 +15,11 @@ void acpi_reboot(void)

rr = &acpi_gbl_FADT.reset_register;

+ /* ACPI reset register was only introduced with v2 of the FADT */
+
+ if (acpi_gbl_FADT.header.revision < 2)
+ return;
+
/* Is the reset register supported? The spec says we should be
* checking the bit width and bit offset, but Windows ignores
* these fields */
--
1.7.4.1