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0f347aa07f
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: 71da201f38 ("ACPI: scan: Defer enumeration of devices with _DEP lists")
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.