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| 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/tbxface.c | |
| parent | c1637e9c649a0eb72c467041d78275aabdd48a41 (diff) | |
| download | linux-729df0f848daf2f17d02107199fa92efe909d995.tar.gz | |
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/tbxface.c')
| -rw-r--r-- | drivers/acpi/acpica/tbxface.c | 32 |
1 files changed, 12 insertions, 20 deletions
diff --git a/drivers/acpi/acpica/tbxface.c b/drivers/acpi/acpica/tbxface.c index 684614d0d327..30565100b94c 100644 --- a/drivers/acpi/acpica/tbxface.c +++ b/drivers/acpi/acpica/tbxface.c @@ -518,33 +518,25 @@ static acpi_status acpi_tb_load_namespace(void) (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); + acpi_gbl_DSDT = &acpi_gbl_root_table_list.tables[ACPI_TABLE_INDEX_DSDT]; + /* - * Load the namespace. The DSDT is required, but any SSDT and PSDT tables - * are optional. + * Load the namespace. The DSDT is required, but any SSDT and + * PSDT tables are optional. Verify the DSDT. */ if (!acpi_gbl_root_table_list.count || - !ACPI_COMPARE_NAME(& - (acpi_gbl_root_table_list. - tables[ACPI_TABLE_INDEX_DSDT].signature), - ACPI_SIG_DSDT) - || - ACPI_FAILURE(acpi_tb_verify_table - (&acpi_gbl_root_table_list. - tables[ACPI_TABLE_INDEX_DSDT]))) { + !ACPI_COMPARE_NAME(&acpi_gbl_DSDT->signature, ACPI_SIG_DSDT) || + ACPI_FAILURE(acpi_tb_verify_table(acpi_gbl_DSDT))) { status = AE_NO_ACPI_TABLES; goto unlock_and_exit; } - /* A valid DSDT is required */ - - status = - acpi_tb_verify_table(&acpi_gbl_root_table_list. - tables[ACPI_TABLE_INDEX_DSDT]); - if (ACPI_FAILURE(status)) { - - status = AE_NO_ACPI_TABLES; - goto unlock_and_exit; - } + /* + * Save the original DSDT header for detection of table corruption + * and/or replacement of the DSDT from outside the OS. + */ + ACPI_MEMCPY(&acpi_gbl_original_dsdt_header, acpi_gbl_DSDT->pointer, + sizeof(struct acpi_table_header)); (void)acpi_ut_release_mutex(ACPI_MTX_TABLES); |