* [PATCH v3 1/2] kbuild: Mark usr_gen_init_cpio as no-dot-config-target
2026-09-25 19:29 [PATCH v3 0/2] Move tool for generating initramfs cpio to scripts/ Nicolas Schier
@ 2026-09-25 19:29 ` Nicolas Schier
2026-09-25 19:33 ` sashiko-bot
2026-09-25 19:29 ` [PATCH v3 2/2] kbuild: Move gen_init_cpio and gen_initramfs.sh to scripts/ Nicolas Schier
2026-09-26 8:34 ` [PATCH v3 0/2] Move tool for generating initramfs cpio " Mike Rapoport
2 siblings, 1 reply; 7+ messages in thread
From: Nicolas Schier @ 2026-09-25 19:29 UTC (permalink / raw)
To: Nathan Chancellor, Nicolas Schier, Jonathan Corbet, Shuah Khan,
Randy Dunlap, Luis Augenstein, Maximilian Huber, Mike Rapoport,
Pasha Tatashin, Pratyush Yadav, Alexander Graf, Willy Tarreau,
Thomas Weißschuh
Cc: linux-kbuild, linux-kernel, Askar Safin, linux-doc, kexec,
linux-mm, linux-kselftest
Let usr/gen_init_cpio be built also if there is no kernel configuration.
Askar Safin reported that gen_init_cpio may be of use before any kernel
configuration is available. Add usr_gen_init_cpio to list of targets
that do not require a .config file.
Reported-by: Askar Safin <safinaskar@gmail.com>
Closes: https://lore.kernel.org/all/20260220191150.244006-1-safinaskar@gmail.com
Fixes: f8e05c10631e ("kbuild: Add top-level target for building gen_init_cpio")
Signed-off-by: Nicolas Schier <nsc@kernel.org>
---
Makefile | 1 +
1 file changed, 1 insertion(+)
diff --git a/Makefile b/Makefile
index 751a08643bf8..51fada9059d6 100644
--- a/Makefile
+++ b/Makefile
@@ -298,6 +298,7 @@ no-dot-config-targets := $(clean-targets) \
%asm-generic kernelversion %src-pkg dt_binding_check \
dt_style_selftest \
outputmakefile rustavailable rustfmt rustfmtcheck \
+ usr_gen_init_cpio \
run-command
no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
image_name
--
2.47.3
^ permalink raw reply [flat|nested] 7+ messages in thread* [PATCH v3 2/2] kbuild: Move gen_init_cpio and gen_initramfs.sh to scripts/
2026-09-25 19:29 [PATCH v3 0/2] Move tool for generating initramfs cpio to scripts/ Nicolas Schier
2026-09-25 19:29 ` [PATCH v3 1/2] kbuild: Mark usr_gen_init_cpio as no-dot-config-target Nicolas Schier
@ 2026-09-25 19:29 ` Nicolas Schier
2026-09-25 19:38 ` sashiko-bot
2026-09-26 8:34 ` [PATCH v3 0/2] Move tool for generating initramfs cpio " Mike Rapoport
2 siblings, 1 reply; 7+ messages in thread
From: Nicolas Schier @ 2026-09-25 19:29 UTC (permalink / raw)
To: Nathan Chancellor, Nicolas Schier, Jonathan Corbet, Shuah Khan,
Randy Dunlap, Luis Augenstein, Maximilian Huber, Mike Rapoport,
Pasha Tatashin, Pratyush Yadav, Alexander Graf, Willy Tarreau,
Thomas Weißschuh
Cc: linux-kbuild, linux-kernel, Askar Safin, linux-doc, kexec,
linux-mm, linux-kselftest, Thomas Weißschuh
gen_init_cpio and gen_initramfs.sh are part of kbuild and required for
all kernel builds w/ CONFIG_BLK_DEV_INITRD. Move both to scripts/ to be
more clear about their importance.
Link: https://lore.kernel.org/all/aSdrCFkUQup3qb-q@derry.ads.avm.de/
Reviewed-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nicolas Schier <nsc@kernel.org>
---
Changes in v3:
* Update other references to usr/gen_init* (Nathan)
---
.../early-userspace/early_userspace_support.rst | 16 ++++++++--------
Documentation/filesystems/ramfs-rootfs-initramfs.rst | 10 +++++-----
MAINTAINERS | 1 +
Makefile | 10 +++++-----
scripts/.gitignore | 1 +
scripts/Makefile | 3 +++
scripts/Makefile.package | 2 +-
{usr => scripts}/gen_init_cpio.c | 0
{usr => scripts}/gen_initramfs.sh | 2 +-
scripts/remove-stale-files | 2 ++
scripts/sbom/tests/cmd_graph/test_savedcmd_parser.py | 2 +-
tools/testing/selftests/kho/vmtest.sh | 2 +-
tools/testing/selftests/nolibc/Makefile.nolibc | 2 +-
usr/.gitignore | 4 +++-
usr/Kconfig | 2 +-
usr/Makefile | 4 +---
16 files changed, 35 insertions(+), 28 deletions(-)
diff --git a/Documentation/driver-api/early-userspace/early_userspace_support.rst b/Documentation/driver-api/early-userspace/early_userspace_support.rst
index 60d1e1bc9413..1070f82e3578 100644
--- a/Documentation/driver-api/early-userspace/early_userspace_support.rst
+++ b/Documentation/driver-api/early-userspace/early_userspace_support.rst
@@ -55,9 +55,9 @@ user root (0). INITRAMFS_ROOT_GID can be set to a group ID that needs
to be mapped to group root (0).
A source file must be directives in the format required by the
-usr/gen_init_cpio utility (run 'usr/gen_init_cpio -h' to get the
+scripts/gen_init_cpio utility (run 'scripts/gen_init_cpio -h' to get the
file format). The directives in the file will be passed directly to
-usr/gen_init_cpio.
+scripts/gen_init_cpio.
When a combination of directories and files are specified then the
initramfs image will be an aggregate of all of them. In this way a user
@@ -69,17 +69,17 @@ early userspace image can be built by an unprivileged user.
As a technical note, when directories and files are specified, the
entire CONFIG_INITRAMFS_SOURCE is passed to
-usr/gen_initramfs.sh. This means that CONFIG_INITRAMFS_SOURCE
+scripts/gen_initramfs.sh. This means that CONFIG_INITRAMFS_SOURCE
can really be interpreted as any legal argument to
gen_initramfs.sh. If a directory is specified as an argument then
the contents are scanned, uid/gid translation is performed, and
-usr/gen_init_cpio file directives are output. If a file is
-specified as an argument to usr/gen_initramfs.sh then the
+scripts/gen_init_cpio file directives are output. If a file is
+specified as an argument to scripts/gen_initramfs.sh then the
contents of the file are simply copied to the output. All of the output
directives from directory scanning and file contents copying are
-processed by usr/gen_init_cpio.
+processed by scripts/gen_init_cpio.
-See also 'usr/gen_initramfs.sh -h'.
+See also 'scripts/gen_initramfs.sh -h'.
Where's this all leading?
=========================
@@ -142,7 +142,7 @@ b) some device and filesystem drivers built as modules and stored in an
c) using initramfs. The call to prepare_namespace() must be skipped.
This means that a binary must do all the work. Said binary can be stored
- into initramfs either via modifying usr/gen_init_cpio.c or via the new
+ into initramfs either via modifying scripts/gen_init_cpio.c or via the new
initrd format, an cpio archive. It must be called "/init". This binary
is responsible to do all the things prepare_namespace() would do.
diff --git a/Documentation/filesystems/ramfs-rootfs-initramfs.rst b/Documentation/filesystems/ramfs-rootfs-initramfs.rst
index 165117a721ce..4263fe06115d 100644
--- a/Documentation/filesystems/ramfs-rootfs-initramfs.rst
+++ b/Documentation/filesystems/ramfs-rootfs-initramfs.rst
@@ -155,7 +155,7 @@ specification such as the following example::
dir /mnt 755 0 0
file /init initramfs/init.sh 755 0 0
-Run "usr/gen_init_cpio" (after the kernel build) to get a usage message
+Run "scripts/gen_init_cpio" (after the kernel build) to get a usage message
documenting the above file format.
One advantage of the configuration file is that root access is not required to
@@ -167,9 +167,9 @@ Documentation/driver-api/early-userspace/early_userspace_support.rst for more de
The kernel does not depend on external cpio tools. If you specify a
directory instead of a configuration file, the kernel's build infrastructure
creates a configuration file from that directory (usr/Makefile calls
-usr/gen_initramfs.sh), and proceeds to package up that directory
-using the config file (by feeding it to usr/gen_init_cpio, which is created
-from usr/gen_init_cpio.c). The kernel's build-time cpio creation code is
+scripts/gen_initramfs.sh), and proceeds to package up that directory
+using the config file (by feeding it to scripts/gen_init_cpio, which is created
+from scripts/gen_init_cpio.c). The kernel's build-time cpio creation code is
entirely self-contained, and the kernel's boot-time extractor is also
(obviously) self-contained.
@@ -313,7 +313,7 @@ the above threads) is:
2) The cpio archive format chosen by the kernel is simpler and cleaner (and
thus easier to create and parse) than any of the (literally dozens of)
various tar archive formats. The complete initramfs archive format is
- explained in buffer-format.rst, created in usr/gen_init_cpio.c, and
+ explained in buffer-format.rst, created in scripts/gen_init_cpio.c, and
extracted in init/initramfs.c. All three together come to less than 26k
total of human-readable text.
diff --git a/MAINTAINERS b/MAINTAINERS
index cc3cae2e378b..6a76fbf6ed57 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14139,6 +14139,7 @@ F: scripts/basic/
F: scripts/clang-tools/
F: scripts/container
F: scripts/dummy-tools/
+F: scripts/gen_init*
F: scripts/include/
F: scripts/install.sh
F: scripts/mk*
diff --git a/Makefile b/Makefile
index 51fada9059d6..bc97a8c08e20 100644
--- a/Makefile
+++ b/Makefile
@@ -298,7 +298,7 @@ no-dot-config-targets := $(clean-targets) \
%asm-generic kernelversion %src-pkg dt_binding_check \
dt_style_selftest \
outputmakefile rustavailable rustfmt rustfmtcheck \
- usr_gen_init_cpio \
+ scripts_gen_init_cpio \
run-command
no-sync-config-targets := $(no-dot-config-targets) %install modules_sign kernelrelease \
image_name
@@ -1529,9 +1529,9 @@ ifdef CONFIG_HEADERS_INSTALL
prepare: headers
endif
-PHONY += usr_gen_init_cpio
-usr_gen_init_cpio: scripts_basic
- $(Q)$(MAKE) $(build)=usr usr/gen_init_cpio
+PHONY += scripts_gen_init_cpio
+scripts_gen_init_cpio: scripts_basic
+ $(Q)$(MAKE) $(build)=scripts scripts/gen_init_cpio
PHONY += scripts_unifdef
scripts_unifdef: scripts_basic
@@ -1832,7 +1832,7 @@ distclean: mrproper
# Packaging of the kernel to various formats
# ---------------------------------------------------------------------------
-modules-cpio-pkg: usr_gen_init_cpio
+modules-cpio-pkg: scripts_gen_init_cpio
%src-pkg: FORCE
$(Q)$(MAKE) -f $(srctree)/scripts/Makefile.package $@
diff --git a/scripts/.gitignore b/scripts/.gitignore
index 4215c2208f7e..700456543910 100644
--- a/scripts/.gitignore
+++ b/scripts/.gitignore
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0-only
/asn1_compiler
+/gen_init_cpio
/gen_packed_field_checks
/generate_rust_target
/insert-sys-cert
diff --git a/scripts/Makefile b/scripts/Makefile
index 3434a82a119f..3d50805b0885 100644
--- a/scripts/Makefile
+++ b/scripts/Makefile
@@ -53,6 +53,9 @@ ifdef CONFIG_BUILDTIME_MCOUNT_SORT
HOSTCFLAGS_sorttable.o += -DMCOUNT_SORT_ENABLED
endif
+hostprogs += gen_init_cpio
+always-$(CONFIG_BLK_DEV_INITRD) += gen_init_cpio
+
# The following programs are only built on demand
hostprogs += unifdef gen_packed_field_checks
diff --git a/scripts/Makefile.package b/scripts/Makefile.package
index 6d36786ba31c..948ad5b679d1 100644
--- a/scripts/Makefile.package
+++ b/scripts/Makefile.package
@@ -198,7 +198,7 @@ tar%-pkg: linux-$(KERNELRELEASE)-$(ARCH).tar.% FORCE
$(Q)$(MAKE) -f $(srctree)/Makefile INSTALL_MOD_PATH=$@/$(INSTALL_MOD_PATH) modules_install
quiet_cmd_cpio = CPIO $@
- cmd_cpio = $(CONFIG_SHELL) $(srctree)/usr/gen_initramfs.sh -o $@ $<
+ cmd_cpio = $(CONFIG_SHELL) $(srctree)/scripts/gen_initramfs.sh -o $@ $<
modules-$(KERNELRELEASE)-$(ARCH).cpio: .tmp_modules_cpio
$(call cmd,cpio)
diff --git a/usr/gen_init_cpio.c b/scripts/gen_init_cpio.c
similarity index 100%
rename from usr/gen_init_cpio.c
rename to scripts/gen_init_cpio.c
diff --git a/usr/gen_initramfs.sh b/scripts/gen_initramfs.sh
similarity index 99%
rename from usr/gen_initramfs.sh
rename to scripts/gen_initramfs.sh
index 7eba2fddf0ef..27ac1fd48001 100755
--- a/usr/gen_initramfs.sh
+++ b/scripts/gen_initramfs.sh
@@ -247,4 +247,4 @@ done
# If output_file is set we will generate cpio archive
# we are careful to delete tmp files
-usr/gen_init_cpio $output $timestamp $cpio_list
+scripts/gen_init_cpio $output $timestamp $cpio_list
diff --git a/scripts/remove-stale-files b/scripts/remove-stale-files
index 6e39fa8540df..e46337e4bfb8 100755
--- a/scripts/remove-stale-files
+++ b/scripts/remove-stale-files
@@ -26,3 +26,5 @@ rm -f scripts/selinux/genheaders/genheaders
rm -f *.spec
rm -f lib/test_fortify.log
+
+rm -f usr/gen_init_cpio
diff --git a/scripts/sbom/tests/cmd_graph/test_savedcmd_parser.py b/scripts/sbom/tests/cmd_graph/test_savedcmd_parser.py
index d7776f072e03..93787a1cd156 100644
--- a/scripts/sbom/tests/cmd_graph/test_savedcmd_parser.py
+++ b/scripts/sbom/tests/cmd_graph/test_savedcmd_parser.py
@@ -338,7 +338,7 @@ class TestSavedCmdParser(unittest.TestCase):
# gen_initramfs.sh command tests
def test_gen_initramfs(self):
- cmd = "sh ../usr/gen_initramfs.sh -o usr/initramfs_data.cpio -l usr/.initramfs_data.cpio.d ../usr/default_cpio_list"
+ cmd = "sh ../scripts/gen_initramfs.sh -o usr/initramfs_data.cpio -l usr/.initramfs_data.cpio.d ../usr/default_cpio_list"
expected = "../usr/default_cpio_list"
self._assert_parsing(cmd, expected)
diff --git a/tools/testing/selftests/kho/vmtest.sh b/tools/testing/selftests/kho/vmtest.sh
index 0014bd76e88d..1e86ffcc3a79 100755
--- a/tools/testing/selftests/kho/vmtest.sh
+++ b/tools/testing/selftests/kho/vmtest.sh
@@ -100,7 +100,7 @@ file /init $tmp_dir/init 0755 0 0
file /kernel $kernel 0644 0 0
EOF
- "$build_dir/usr/gen_init_cpio" "$tmp_dir/cpio_list" > "$initrd"
+ "$build_dir/scripts/gen_init_cpio" "$tmp_dir/cpio_list" > "$initrd"
}
function run_qemu() {
diff --git a/tools/testing/selftests/nolibc/Makefile.nolibc b/tools/testing/selftests/nolibc/Makefile.nolibc
index f70c8dfca018..380200b152e4 100644
--- a/tools/testing/selftests/nolibc/Makefile.nolibc
+++ b/tools/testing/selftests/nolibc/Makefile.nolibc
@@ -295,7 +295,7 @@ run-user: nolibc-test
$(Q)$(REPORT) $(CURDIR)/run.out
initramfs.cpio: kernel nolibc-test
- $(QUIET_GEN)echo 'file /init nolibc-test 755 0 0' | $(objtree)/usr/gen_init_cpio - > initramfs.cpio
+ $(QUIET_GEN)echo 'file /init nolibc-test 755 0 0' | $(objtree)/scripts/gen_init_cpio - > initramfs.cpio
initramfs: nolibc-test
$(QUIET_MKDIR)mkdir -p initramfs
diff --git a/usr/.gitignore b/usr/.gitignore
index 8996e7a88902..13bf7a38355c 100644
--- a/usr/.gitignore
+++ b/usr/.gitignore
@@ -1,4 +1,6 @@
# SPDX-License-Identifier: GPL-2.0-only
-/gen_init_cpio
/initramfs_data.cpio
/initramfs_inc_data
+
+# Keep around until cleanup in scripts/remove-stale-files
+/gen_init_cpio
diff --git a/usr/Kconfig b/usr/Kconfig
index 9279a2893ab0..f87dd4bac418 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -13,7 +13,7 @@ config INITRAMFS_SOURCE
to be used as an initramfs image. Directories should contain a
filesystem layout to be included in the initramfs image. Files
should contain entries according to the format described by the
- "usr/gen_init_cpio" program in the kernel tree.
+ "scripts/gen_init_cpio" program in the kernel tree.
When multiple directories and files are specified then the
initramfs image will be the aggregate of all of them.
diff --git a/usr/Makefile b/usr/Makefile
index e8f42478a0b7..5b97ee66c00a 100644
--- a/usr/Makefile
+++ b/usr/Makefile
@@ -16,8 +16,6 @@ obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
$(obj)/initramfs_data.o: $(obj)/initramfs_inc_data
-hostprogs := gen_init_cpio
-
ramfs-input := $(CONFIG_INITRAMFS_SOURCE)
cpio-data :=
@@ -72,7 +70,7 @@ quiet_cmd_initfs = GEN $@
# 2) There are changes in which files are included (added or deleted)
# 3) If gen_init_cpio are newer than initramfs_data.cpio
# 4) Arguments to gen_initramfs.sh changes
-$(obj)/initramfs_data.cpio: $(src)/gen_initramfs.sh $(obj)/gen_init_cpio $(deps_initramfs) FORCE
+$(obj)/initramfs_data.cpio: $(srctree)/scripts/gen_initramfs.sh scripts/gen_init_cpio $(deps_initramfs) FORCE
$(call if_changed,initfs)
endif
--
2.47.3
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH v3 0/2] Move tool for generating initramfs cpio to scripts/
2026-09-25 19:29 [PATCH v3 0/2] Move tool for generating initramfs cpio to scripts/ Nicolas Schier
2026-09-25 19:29 ` [PATCH v3 1/2] kbuild: Mark usr_gen_init_cpio as no-dot-config-target Nicolas Schier
2026-09-25 19:29 ` [PATCH v3 2/2] kbuild: Move gen_init_cpio and gen_initramfs.sh to scripts/ Nicolas Schier
@ 2026-09-26 8:34 ` Mike Rapoport
2026-09-26 17:48 ` Nicolas Schier
2 siblings, 1 reply; 7+ messages in thread
From: Mike Rapoport @ 2026-09-26 8:34 UTC (permalink / raw)
To: Nicolas Schier
Cc: Nathan Chancellor, Jonathan Corbet, Shuah Khan, Randy Dunlap,
Luis Augenstein, Maximilian Huber, Pasha Tatashin,
Pratyush Yadav, Alexander Graf, Willy Tarreau,
Thomas Weißschuh, linux-kbuild, linux-kernel, Askar Safin,
linux-doc, kexec, linux-mm, linux-kselftest,
Thomas Weißschuh
Hi Nicolas,
On Fri, Sep 25, 2026 at 09:29:29PM +0200, Nicolas Schier wrote:
> initramfs cpio tools had been subject of several recent discussions on
> linux-kbuild. Let's get two minor steps forward by enabling a
> top-level target for building gen_init_cpio w/o the need of a valid
> kbuild configuration [1] and move the tools for generating the built-in
> initramfs from usr/ to scripts/ [2].
>
> Link: https://lore.kernel.org/all/20260220191150.244006-1-safinaskar@gmail.com # [1]
> Link: https://lore.kernel.org/all/aSdrCFkUQup3qb-q@derry.ads.avm.de/ # [2]
> ---
> Changes in v3:
> * Update various remaining usr/gen_init* references treewide (Nathan)
> * Link to v2: https://patch.msgid.link/20260720-move-gen_init_cpio-to-scripts-v2-0-26b7e15c7133@kernel.org
>
> Changes in v2:
> * Build gen_init_cpio only if CONFIG_BLK_DEV_INITRD (Thomas)
> * Keep underscore top-level target name (scripts_gen_init_cpio)
> (Thomas)
> * Link to v1: https://patch.msgid.link/20260309-move-gen_init_cpio-to-scripts-v1-0-0c5059b1ec5b@kernel.org
>
> ---
> Nicolas Schier (2):
> kbuild: Mark usr_gen_init_cpio as no-dot-config-target
> kbuild: Move gen_init_cpio and gen_initramfs.sh to scripts/
>
> .../early-userspace/early_userspace_support.rst | 16 ++++++++--------
> Documentation/filesystems/ramfs-rootfs-initramfs.rst | 10 +++++-----
> MAINTAINERS | 1 +
> Makefile | 9 +++++----
> scripts/.gitignore | 1 +
> scripts/Makefile | 3 +++
> scripts/Makefile.package | 2 +-
> {usr => scripts}/gen_init_cpio.c | 0
> {usr => scripts}/gen_initramfs.sh | 2 +-
> scripts/remove-stale-files | 2 ++
> scripts/sbom/tests/cmd_graph/test_savedcmd_parser.py | 2 +-
> tools/testing/selftests/kho/vmtest.sh | 2 +-
There's also tools/testing/selftests/liveupdate/vmtest.sh I know of, didn't
check for other users in tools/testing
> tools/testing/selftests/nolibc/Makefile.nolibc | 2 +-
> usr/.gitignore | 4 +++-
> usr/Kconfig | 2 +-
> usr/Makefile | 4 +---
> 16 files changed, 35 insertions(+), 27 deletions(-)
> ---
> base-commit: 93f51579e7df248780214094418f205253383cc5
> change-id: 20260225-move-gen_init_cpio-to-scripts-9e89ef99e51a
>
> Best regards,
> --
> Nicolas
>
--
Sincerely yours,
Mike.
^ permalink raw reply [flat|nested] 7+ messages in thread