On Mon, Jun 12, 2023 at 01:27:52PM -0400, Eric DeVolder wrote:
The Kconfig is refactored to consolidate KEXEC and CRASH options from
various arch/<arch>/Kconfig files into new file kernel/Kconfig.kexec.
This looks very nice!
[...]
- The boolean ARCH_HAS_<option> in effect allows the arch to determine
when the feature is allowed. Archs which don't have the feature
simply do not provide the corresponding ARCH_HAS_<option>.
For each arch, where there previously were KEXEC and/or CRASH
options, these have been replaced with the corresponding boolean
ARCH_HAS_<option>, and an appropriate def_bool statement.
For example, if the arch supports KEXEC_FILE, then the
ARCH_HAS_KEXEC_FILE simply has a 'def_bool y'. This permits the
KEXEC_FILE option to be available.
If the arch has a 'depends on' statement in its original coding
of the option, then that expression becomes part of the def_bool
expression. For example, arm64 had:
config KEXEC
depends on PM_SLEEP_SMP
and in this solution, this converts to:
config ARCH_HAS_KEXEC
def_bool PM_SLEEP_SMP
- In order to account for the differences in the config coding for
the three common options, the ARCH_SUPPORTS_<option> is used.
This options has a 'depends on <option>' statement to couple it
to the main option, and from there can insert the differences
from the common option and the arch original coding of that option.
For example, a few archs enable CRYPTO and CRYTPO_SHA256 for
KEXEC_FILE. These require a ARCH_SUPPORTS_KEXEC_FILE and
'select CRYPTO' and 'select CRYPTO_SHA256' statements.
Naming nit: "HAS" and "SUPPORTS" feel very similar, and looking at
existing configs, "ARCH_SUPPORTS_..." is already used for doing this
kind of bare "bool" management. e.g. see ARCH_SUPPORTS_INT128
It looks like you need to split "depends" and "select" so the options
can be chosen separately from the "selectable" configs.
How about naming this ARCH_SELECTS_<option>, since that's what it's
there for?
-Kees
--
Kees Cook
