cacheinfo: Make default acpi_get_cache_info() return an error
authorPierre Gondois <pierre.gondois@arm.com>
Tue, 24 Jan 2023 15:40:47 +0000 (16:40 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 31 Jan 2023 15:02:02 +0000 (16:02 +0100)
commitd931b83e62b1dd352fc326c0b1cf3be3ef19e113
tree2ef0edb6f0fde2f697a4846ccb7df24ce0ed408a
parentecaef469920fd6d2c7687f19081946f47684a423
cacheinfo: Make default acpi_get_cache_info() return an error

commit bd500361a937 ("ACPI: PPTT: Update acpi_find_last_cache_level()
to acpi_get_cache_info()")
updates the prototype of acpi_get_cache_info(). The cache 'levels'
is update through a pointer and not the return value of the function.

If CONFIG_ACPI_PPTT is not defined, acpi_get_cache_info() doesn't
update its *levels and *split_levels parameters and returns 0.
This can lead to a faulty behaviour.

Make acpi_get_cache_info() return an error code if CONFIG_ACPI_PPTT
is not defined.
Also,

In init_cache_level(), if no PPTT is present or CONFIG_ACPI_PPTT is
not defined, instead of aborting if acpi_get_cache_info() returns an
error code, just continue. This allows to try fetching the cache
information from clidr_el1.

Signed-off-by: Pierre Gondois <pierre.gondois@arm.com>
Link: https://lore.kernel.org/r/20230124154053.355376-3-pierre.gondois@arm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/arm64/kernel/cacheinfo.c
include/linux/cacheinfo.h