From c7ff693fa2094ba0a9d0a20feb4ab1658eff9c33 Mon Sep 17 00:00:00 2001 From: Petr Pavlu Date: Mon, 22 Jul 2024 11:06:21 +0200 Subject: module: Split modules_install compression and in-kernel decompression The kernel configuration allows specifying a module compression mode. If one is selected then each module gets compressed during 'make modules_install' and additionally one can also enable support for a respective direct in-kernel decompression support. This means that the decompression support cannot be enabled without the automatic compression. Some distributions, such as the (open)SUSE family, use a signer service for modules. A build runs on a worker machine but signing is done by a separate locked-down server that is in possession of the signing key. The build invokes 'make modules_install' to create a modules tree, collects information about the modules, asks the signer service for their signature, appends each signature to the respective module and compresses all modules. When using this arrangment, the 'make modules_install' step produces unsigned+uncompressed modules and the distribution's own build recipe takes care of signing and compression later. The signing support can be currently enabled without automatically signing modules during 'make modules_install'. However, the in-kernel decompression support can be selected only after first enabling automatic compression during this step. To allow only enabling the in-kernel decompression support without the automatic compression during 'make modules_install', separate the compression options similarly to the signing options, as follows: > Enable loadable module support [*] Module compression Module compression type (GZIP) ---> [*] Automatically compress all modules [ ] Support in-kernel module decompression * "Module compression" (MODULE_COMPRESS) is a new main switch for the compression/decompression support. It replaces MODULE_COMPRESS_NONE. * "Module compression type" (MODULE_COMPRESS_) chooses the compression type, one of GZ, XZ, ZSTD. * "Automatically compress all modules" (MODULE_COMPRESS_ALL) is a new option to enable module compression during 'make modules_install'. It defaults to Y. * "Support in-kernel module decompression" (MODULE_DECOMPRESS) enables in-kernel decompression. Signed-off-by: Petr Pavlu Acked-by: Masahiro Yamada Signed-off-by: Luis Chamberlain --- scripts/Makefile.modinst | 2 ++ 1 file changed, 2 insertions(+) (limited to 'scripts/Makefile.modinst') diff --git a/scripts/Makefile.modinst b/scripts/Makefile.modinst index 0afd75472679..bce4a9adb893 100644 --- a/scripts/Makefile.modinst +++ b/scripts/Makefile.modinst @@ -51,9 +51,11 @@ $(foreach x, % :, $(if $(findstring $x, $(dst)), \ $(error module installation path cannot contain '$x'))) suffix-y := +ifdef CONFIG_MODULE_COMPRESS_ALL suffix-$(CONFIG_MODULE_COMPRESS_GZIP) := .gz suffix-$(CONFIG_MODULE_COMPRESS_XZ) := .xz suffix-$(CONFIG_MODULE_COMPRESS_ZSTD) := .zst +endif modules := $(patsubst $(extmod_prefix)%.o, $(dst)/%.ko$(suffix-y), $(modules)) install-$(CONFIG_MODULES) += $(modules) -- cgit v1.2.3-70-g09d2