With the new 2 step scanning process, which defers instantiating some
ACPI-devices based on their _DEP to the second step, the following may
happen:
1. During the first acpi_walk_namespace(acpi_bus_check_add) call
acpi_scan_check_dep() gets called on the Battery ACPI dev handle and
adds one or more deps for this handle to the acpi_dep_list
2. During the first acpi_bus_attach() call one or more of the suppliers of
these deps get their driver attached and
acpi_walk_dep_device_list(supplier_handle) gets called.
At this point acpi_bus_get_device(dep->consumer) get called,
but since the battery has DEPs it has not been instantiated during the
first acpi_walk_namespace(acpi_bus_check_add), so the
acpi_bus_get_device(dep->consumer) call fails.
Before this commit, acpi_walk_dep_device_list() would now continue
*without* removing the acpi_dep_data entry for this supplier,consumer
pair from the acpi_dep_list.
3. During the second acpi_walk_namespace(acpi_bus_check_add) call
an acpi_device gets instantiated for the battery and
acpi_scan_dep_init() gets called to initialize its dep_unmet val.
Before this commit, the dep_unmet count would include DEPs for
suppliers for which acpi_walk_dep_device_list(supplier_handle)
has already been called, so it will never become 0 and the
ACPI battery driver will never get attached / bind.
Fix the ACPI battery driver never binding in this scenario by making
acpi_walk_dep_device_list() always remove matching acpi_dep_data
entries independent of the acpi_bus_get_device(dep->consumer) call
succeeding or not.
Fixes: 71da201f38df ("ACPI: scan: Defer enumeration of devices with _DEP lists")
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/acpi/scan.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 5d7b2fcecf06..4ce54115e981 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -2123,12 +2123,12 @@ void acpi_walk_dep_device_list(acpi_handle handle)
list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
if (dep->supplier == handle) {
acpi_bus_get_device(dep->consumer, &adev);
- if (!adev)
- continue;
- adev->dep_unmet--;
- if (!adev->dep_unmet)
- acpi_bus_attach(adev, true);
+ if (adev) {
+ adev->dep_unmet--;
+ if (!adev->dep_unmet)
+ acpi_bus_attach(adev, true);
+ }
list_del(&dep->node);
kfree(dep);
--
2.29.2
