diff options
author | Lin Ming <ming.m.lin@intel.com> | 2010-04-01 10:47:56 +0800 |
---|---|---|
committer | Len Brown <len.brown@intel.com> | 2010-04-20 10:43:16 -0400 |
commit | 729df0f848daf2f17d02107199fa92efe909d995 (patch) | |
tree | d4ece34a277019368999fd36a0bf15a39eeaa742 /drivers/acpi/acpica/tbutils.c | |
parent | c1637e9c649a0eb72c467041d78275aabdd48a41 (diff) |
ACPICA: Add detection of corrupted/replaced DSDT
This change adds support to detect a DSDT that has been corrupted
and/or replaced from outside the OS (by firmware). This is
typically catastrophic for the system, but has been seen on
some machines.
https://bugzilla.kernel.org/show_bug.cgi?id=14679
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/acpica/tbutils.c')
-rw-r--r-- | drivers/acpi/acpica/tbutils.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/tbutils.c b/drivers/acpi/acpica/tbutils.c index f47a70e20063..07bc7437f82b 100644 --- a/drivers/acpi/acpica/tbutils.c +++ b/drivers/acpi/acpica/tbutils.c @@ -349,6 +349,44 @@ u8 acpi_tb_checksum(u8 *buffer, u32 length) /******************************************************************************* * + * FUNCTION: acpi_tb_check_dsdt_header + * + * PARAMETERS: None + * + * RETURN: None + * + * DESCRIPTION: Quick compare to check validity of the DSDT. This will detect + * if the DSDT has been replaced from outside the OS and/or if + * the DSDT header has been corrupted. + * + ******************************************************************************/ + +void acpi_tb_check_dsdt_header(void) +{ + + /* Compare original length and checksum to current values */ + + if (acpi_gbl_original_dsdt_header.length != + acpi_gbl_DSDT->pointer->length + || acpi_gbl_original_dsdt_header.checksum != + acpi_gbl_DSDT->pointer->checksum) { + ACPI_ERROR((AE_INFO, + "The DSDT has been corrupted or replaced - old, new headers below")); + acpi_tb_print_table_header(0, &acpi_gbl_original_dsdt_header); + acpi_tb_print_table_header(acpi_gbl_DSDT->address, + acpi_gbl_DSDT->pointer); + + /* Disable further error messages */ + + acpi_gbl_original_dsdt_header.length = + acpi_gbl_DSDT->pointer->length; + acpi_gbl_original_dsdt_header.checksum = + acpi_gbl_DSDT->pointer->checksum; + } +} + +/******************************************************************************* + * * FUNCTION: acpi_tb_install_table * * PARAMETERS: Address - Physical address of DSDT or FACS |