diff options
| author | Bob Moore <robert.moore@intel.com> | 2009-03-09 16:31:04 +0800 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2009-03-27 12:11:02 -0400 |
| commit | 8a335a2331c72e60c6b3ef09b2dedd3ba00da1b1 (patch) | |
| tree | f538a4f68499dab0d59e253bc55a5cf4aff66ec1 /drivers/acpi/acpica/dsinit.c | |
| parent | aab61b676a024d3527f6201e2b31285a96f7a1d2 (diff) | |
ACPICA: Fix AcpiWalkNamespace race condition with table unload
Added a reader/writer locking mechanism to allow multiple
concurrent namespace walks (readers), but a dynamic table unload
will have exclusive access to the namespace. This fixes a problem
where a table unload could delete the portion of the namespace that
is currently being examined by a walk. Adds a new file, utlock.c
that implements the reader/writer lock mechanism. ACPICA BZ 749.
http://www.acpica.org/bugzilla/show_bug.cgi?id=749
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/acpica/dsinit.c')
| -rw-r--r-- | drivers/acpi/acpica/dsinit.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/drivers/acpi/acpica/dsinit.c b/drivers/acpi/acpica/dsinit.c index eb144b13d8f..3aae13f30c5 100644 --- a/drivers/acpi/acpica/dsinit.c +++ b/drivers/acpi/acpica/dsinit.c @@ -180,11 +180,23 @@ acpi_ds_initialize_objects(u32 table_index, /* Walk entire namespace from the supplied root */ - status = acpi_walk_namespace(ACPI_TYPE_ANY, start_node, ACPI_UINT32_MAX, - acpi_ds_init_one_object, &info, NULL); + status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE); + if (ACPI_FAILURE(status)) { + return_ACPI_STATUS(status); + } + + /* + * We don't use acpi_walk_namespace since we do not want to acquire + * the namespace reader lock. + */ + status = + acpi_ns_walk_namespace(ACPI_TYPE_ANY, start_node, ACPI_UINT32_MAX, + ACPI_NS_WALK_UNLOCK, acpi_ds_init_one_object, + &info, NULL); if (ACPI_FAILURE(status)) { ACPI_EXCEPTION((AE_INFO, status, "During WalkNamespace")); } + (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE); status = acpi_get_table_by_index(table_index, &table); if (ACPI_FAILURE(status)) { |