feature add modules

Feature: add-modules

Feature adds kernel modules to initramfs.

Parameters

• MODULES_ADD -- The parameter contains the names of modules to be added to the image. Thay can be loaded by udev if needed when it starts.
• MODULES_TRY_ADD -- Like MODULES_ADD, but image generation won't fail if module is missing.
• MODULES_PRELOAD -- The parameter contains the names of modules to be added to the image and unconditionally loaded before udev start.
• MODULES_LOAD -- The parameter contains the names of modules to be added to the image and unconditionally loaded after udev start.
• RESCUE_MODULES -- The names of modules to be loaded if emergency shell called.
• BLACKLIST_MODULES -- The names of modules that should NOT present in the image.
• MODULES_PATTERN_SETS -- This variable contains names of other variables with a list of rules for filtering (see Pattern sets).

Pattern sets

Pattern set is a collection of filters that are applied simultaneously to find kernel modules. The kernel module will be added to the image only when it satisfies all the rules in the set.

Pattern set format: field:regular-expression

The field can be one of the words: alias, author, depends, description, filename, firmware, license, name, symbol. The fields correspond to the metadata in the kernel module. If you want to invert the expression, then before the field, you need to specify the prefix not-. For example filename and not-filename.

If you specify a regular expression for symbols, keep in mind that it will be applied to both provided and required symbols.

Example of rules.mk:

FILESYSTEM_PATTERN_SET =
FILESYSTEM_PATTERN_SET += alias:^fs-
FILESYSTEM_PATTERN_SET += not-filename:.*/kernel/arch/.*
FILESYSTEM_PATTERN_SET += not-filename:.*/net/.*
MODULES_PATTERN_SETS += FILESYSTEM_PATTERN_SET

This set is intended to find all modules whose alias starts with fs- that are not contains /kernel/arch/ or /net/ in the path.

The rules can be checked with the initrd-scanmod utility. The utility uses a slightly different rule format.

Example:

$ cat >/tmp/scanmod.rules <<EOF
alias ^fs-
not-filename .*/kernel/arch/.*
not-filename .*/net/.*
EOF

$ initrd-scanmod --set-version="$(uname -r)" /tmp/scanmod.rules