[PATCH 1/1] Add support to build binary version of DKMS kernel modules

[Felix Moessbauer]

This patch adds support to build and install a kernel module that is available
via a debian DKMS package.
As it is hard to directly build and install the package we create and distribute
a meta package that is independent of the kernel version.
In that package, we depend on the versioned prebuild kernel module package.

To build the dkms module, we add two tasks and directly
use dkms to build the debian package containing the binary module
Then we just copy the binary-module debian package to the workdir,

Signed-off-by: Felix Moessbauer <felix.mo...@siemens.com>
---
.../example-dkms-module/igb-uio_20.11.bb | 14 ++++
meta/classes/dkms-module.bbclass | 68 +++++++++++++++++++
2 files changed, 82 insertions(+)
create mode 100644 meta-isar/recipes-kernel/example-dkms-module/igb-uio_20.11.bb
create mode 100644 meta/classes/dkms-module.bbclass

diff --git a/meta-isar/recipes-kernel/example-dkms-module/igb-uio_20.11.bb b/meta-isar/recipes-kernel/example-dkms-module/igb-uio_20.11.bb
new file mode 100644
index 0000000..abb9922
--- /dev/null
+++ b/meta-isar/recipes-kernel/example-dkms-module/igb-uio_20.11.bb
@@ -0,0 +1,14 @@
+# Example recipe for building the binary version of a DKMS module
+#
+# This software is a part of ISAR.
+# Copyright (c) Siemens AG, 2018
+#
+# SPDX-License-Identifier: MIT
+
+inherit dkms-module
+
+PN .= "-${KERNEL_NAME}"
+
+#package name (without -dkms. E.g "dpdk-kmods" for package "dpdk-kmods-dkms")
+DKMS_PACKAGE_NAME = "dpdk-kmods"
+AUTOLOAD += "igb_uio"
diff --git a/meta/classes/dkms-module.bbclass b/meta/classes/dkms-module.bbclass
new file mode 100644
index 0000000..d1dbba9
--- /dev/null
+++ b/meta/classes/dkms-module.bbclass
@@ -0,0 +1,68 @@
+# This software is a part of ISAR.
+# Copyright (C) 2021 Siemens AG
+#
+# SPDX-License-Identifier: MIT
+
+inherit dpkg-raw
+
+# Build and install a kernel module that is available via a debian DKMS package.
+# As it is hard to directly build and install the package we create and distribute
+# a meta package that is independent of the kernel version.
+# In that package, we depend on the versioned prebuild kernel module package.
+#
+# To build the dkms module, we add two tasks and directly
+# use dkms to build the debian package containing the binary module
+# Then we just copy the binary-module debian package to the workdir,
+# so ISAR's do_deploy_deb picks it up.
+
+#package name (without -dkms. E.g "dpdk-kmods" for package "dpdk-kmods-dkms")
+DKMS_PACKAGE_NAME ?= ""
+AUTOLOAD ?= ""
+
+DESCRIPTION ?= "Kernel module from DKMS package for ${PN}"
+DEPENDS += "linux-headers-${KERNEL_NAME}"
+DEBIAN_DEPENDS += "${DKMS_PACKAGE_NAME}-modules,"
+DEBIAN_BUILD_DEPENDS += "linux-headers-${KERNEL_NAME}, ${DKMS_PACKAGE_NAME}-dkms,"
+
+# install configuration to auto-load the modules in ${AUTOLOAD}
+do_install() {
+ # auto load the module
+ install -v -d ${D}/etc/modules-load.d
+ for module in "${AUTOLOAD}"; do
+ echo $module > ${D}/etc/modules-load.d/${PN}.conf
+ done
+}
+
+# build the binary kernel module and package as debian package (versioned)
+do_module_build() {
+ # we have to find out the module version, e.g. dpdk-kmods/0~20201113+git -k 5.10.0-3-rt-amd64/x86_64
+ REVISION=$(find ${BUILDCHROOT_DIR}/usr/src/${DKMS_PACKAGE_NAME}-* -type d -exec basename {} + | sed 's/${DKMS_PACKAGE_NAME}-//g')
+ if ! dpkg -s --root=${BUILDCHROOT_DIR} linux-headers-${KERNEL_NAME} | grep "Depends:.*linux-headers"; then
+ # custom kernels directly place their files in linux-image-KERNEL-NAME, instead
+ # of using a meta package + a versioned package with the resources
+ # The prebuild DKMS binary package depends on the versioned kernel package,
+ # but that is not available on custom kernels. Hence, we just remove the dependency.
+ bbnote "Building ${DKMS_PACKAGE_NAME} for custom kernel ${KERNEL_NAME}"
+ cp ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control ${WORKDIR}/control.dkms.orig
+ sudo sed -i 's/, linux-image-KERNEL_VERSION//' ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control
+ fi
+ # build the module for all installed kernels (should be just one)
+ sudo -E chroot ${BUILDCHROOT_DIR} dkms mkbmdeb ${DKMS_PACKAGE_NAME}/${REVISION} --all
+ DKMS_PACKAGE_VERSIONED=$(find ${BUILDCHROOT_DIR}/var/lib/dkms/${DKMS_PACKAGE_NAME}/ -name "${DKMS_PACKAGE_NAME}-modules*.deb" -exec dpkg -I {} + | grep "Package:" | awk '{print $2}')
+ if [ -z "$DKMS_PACKAGE_VERSIONED" ]; then
+ bberror "No prebuild dkms module found"
+ exit 1
+ fi
+ # restore dkms template (if any)
+ cp ${WORKDIR}/control.dkms.orig ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control || true
+}
+
+# simply copy our module from the build tree to the expected output location
+# of this recipe. Then, do_deploy_dep finds it and adds it to the
+# debian isar repo
+do_module_deploy() {
+ cp ${BUILDCHROOT_DIR}/var/lib/dkms/${DKMS_PACKAGE_NAME}/*/bmdeb/*.deb ${S}/../
+}
+
+addtask module_build after do_install_builddeps before do_dpkg_build
+addtask module_deploy after do_module_build before do_deploy_deb
--
2.20.1

[Henning Schild]

Hi Felix,

thanks for pushing this one upstream.

We will need a testcase for it, so make sure to enter into
"scripts/ci_build.sh"

I would suggest the virtualbox modules or maybe vmware modules instead.
This way we would probably have more distro coverage and in fact have a
useful example for people doing virtualbox (the one i would prefer).
Not sure that is possible or why you picked dpdk.

Am Wed, 14 Apr 2021 10:36:17 +0200
schrieb Felix Moessbauer <felix.mo...@siemens.com>:

I think this might need an "update-initramfs -u" in postinst, but i am
not sure, check the other autoloader code and see if you can share.
Such modules probably do not need early loading in initrd, but
"/etc/modules-load.d" is mirrored into the initrd so we should not get
out of sync.
It is important that both autoloaders do the same or similar things,
initrd could stay open if the other one also does not care.

Henning

[Jan Kiszka]

On 14.04.21 10:52, Henning Schild wrote:
> Hi Felix,
>
> thanks for pushing this one upstream.
>
> We will need a testcase for it, so make sure to enter into
> "scripts/ci_build.sh"
>
> I would suggest the virtualbox modules or maybe vmware modules instead.
> This way we would probably have more distro coverage and in fact have a
> useful example for people doing virtualbox (the one i would prefer).
> Not sure that is possible or why you picked dpdk.

None of those crappy modules will build on non-x86. We should look for a
portable example.

Jan

--
Siemens AG, T RDA IOT
Corporate Competence Center Embedded Linux

[Henning Schild]

Am Wed, 14 Apr 2021 11:03:50 +0200
schrieb Jan Kiszka <jan.k...@siemens.com>:

> On 14.04.21 10:52, Henning Schild wrote:
> > Hi Felix,
> >
> > thanks for pushing this one upstream.
> >
> > We will need a testcase for it, so make sure to enter into
> > "scripts/ci_build.sh"
> >
> > I would suggest the virtualbox modules or maybe vmware modules
> > instead. This way we would probably have more distro coverage and
> > in fact have a useful example for people doing virtualbox (the one
> > i would prefer). Not sure that is possible or why you picked dpdk.
>
> None of those crappy modules will build on non-x86. We should look
> for a portable example.

Yes ideally we find a dkms package that exists on all distros and
arches, not sure that exists. Would also allow testing the Isar
crossbuild on that feature.

If cross causes issues ISAR_CROSS_COMPILE = "0" in the class might be
acceptable, would be to me.

If we do not find such a generic module, all i said is that vbox is
probably more useful than igb_uio. And probably more available across
distros.

Henning

[Raphael Lisicki]

Hi,

maybe V4L2 loopback could be this example module:
https://packages.debian.org/buster/v4l2loopback-dkms

best regards
Raphael

[Jan Kiszka]

On 15.04.21 14:26, Henning Schild wrote:
> Am Wed, 14 Apr 2021 11:03:50 +0200
> schrieb Jan Kiszka <jan.k...@siemens.com>:
>
>> On 14.04.21 10:52, Henning Schild wrote:
>>> Hi Felix,
>>>
>>> thanks for pushing this one upstream.
>>>
>>> We will need a testcase for it, so make sure to enter into
>>> "scripts/ci_build.sh"
>>>
>>> I would suggest the virtualbox modules or maybe vmware modules
>>> instead. This way we would probably have more distro coverage and
>>> in fact have a useful example for people doing virtualbox (the one
>>> i would prefer). Not sure that is possible or why you picked dpdk.
>>
>> None of those crappy modules will build on non-x86. We should look
>> for a portable example.
>
> Yes ideally we find a dkms package that exists on all distros and
> arches, not sure that exists. Would also allow testing the Isar
> crossbuild on that feature.
>
> If cross causes issues ISAR_CROSS_COMPILE = "0" in the class might be
> acceptable, would be to me.
>

Would enforce CROSS = "0" on a potential custom kernel as well, just to
remind this.

Jan

[Moessbauer, Felix]

Hi,

I just added it to the CI and did some early tests with the v4l2loopback module.
For x86 and arm64, things run smooth, but for armv7 the module cannot be build (even after disabling crossbuilds).

This seems to be not an ISAR issue, but an upstream bug in the module DKMS itself.

I'll have a closer look at that and push a v2 soon.

Best regards,
Felix

> >>>> +# # This software is a part of ISAR.

> >>>> +# To build the dkms module, we add two tasks and directly # use
> >>>> +dkms to build the debian package containing the binary

[Jan Kiszka]

On 19.04.21 14:45, Moessbauer, Felix (T RDA IOT SES-DE) wrote:
> Hi,
>
> I just added it to the CI and did some early tests with the v4l2loopback module.
> For x86 and arm64, things run smooth, but for armv7 the module cannot be build (even after disabling crossbuilds).
>
> This seems to be not an ISAR issue, but an upstream bug in the module DKMS itself.
>
> I'll have a closer look at that and push a v2 soon.

If it is an upstream bug, excluding that arch for now (with reference to
the Debian bug) would be fine.

Jan

[Anton Mikanovich]

14.04.2021 11:36, Felix Moessbauer wrote:
> diff --git a/meta-isar/recipes-kernel/example-dkms-module/igb-uio_20.11.bb b/meta-isar/recipes-kernel/example-dkms-module/igb-uio_20.11.bb
> new file mode 100644
> index 0000000..abb9922
> --- /dev/null
> +++ b/meta-isar/recipes-kernel/example-dkms-module/igb-uio_20.11.bb
> @@ -0,0 +1,14 @@
> +# Example recipe for building the binary version of a DKMS module
> +#
> +# This software is a part of ISAR.
> +# Copyright (c) Siemens AG, 2018

Should it be 2021 maybe?

> +#
> +# SPDX-License-Identifier: MIT
> +
> +inherit dkms-module
> +
> +PN .= "-${KERNEL_NAME}"
> +
> +#package name (without -dkms. E.g "dpdk-kmods" for package "dpdk-kmods-dkms")
> +DKMS_PACKAGE_NAME = "dpdk-kmods"
> +AUTOLOAD += "igb_uio"

--
Anton Mikanovich
Promwad Ltd.
External service provider of ilbers GmbH
Maria-Merian-Str. 8
85521 Ottobrunn, Germany
+49 (89) 122 67 24-0
Commercial register Munich, HRB 214197
General Manager: Baurzhan Ismagulov

[Felix Moessbauer]

This patch adds support to build and install a kernel module that is available
via a debian DKMS package.
As it is hard to directly build and install the package we create and distribute
a meta package that is independent of the kernel version.
In that package, we depend on the versioned prebuild kernel module package.

To build the dkms module, we add two tasks and directly
use dkms to build the debian package containing the binary module
Then we just copy the binary-module debian package to the workdir,

Signed-off-by: Felix Moessbauer <felix.mo...@siemens.com>
---

meta-isar/conf/local.conf.sample | 2 +-
.../example-dkms-module.bb | 14 ++++
meta/classes/dkms-module.bbclass | 70 +++++++++++++++++++
scripts/ci_build.sh | 1 +
4 files changed, 86 insertions(+), 1 deletion(-)
create mode 100644 meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb
create mode 100644 meta/classes/dkms-module.bbclass

diff --git a/meta-isar/conf/local.conf.sample b/meta-isar/conf/local.conf.sample
index 77585ec..678d2f0 100644
--- a/meta-isar/conf/local.conf.sample
+++ b/meta-isar/conf/local.conf.sample
@@ -178,7 +178,7 @@ CONF_VERSION = "1"

#
# The default list of extra packages to be installed.
-IMAGE_INSTALL = "hello-isar example-raw example-module-${KERNEL_NAME} enable-fsck isar-exclude-docs samefile hello isar-disable-apt-cache cowsay example-prebuilt"
+IMAGE_INSTALL = "hello-isar example-raw example-module-${KERNEL_NAME} example-dkms-module-${KERNEL_NAME} enable-fsck isar-exclude-docs samefile hello isar-disable-apt-cache cowsay example-prebuilt"

#
# Enable cross-compilation support
diff --git a/meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb b/meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb
new file mode 100644
index 0000000..113f232
--- /dev/null
+++ b/meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb

@@ -0,0 +1,14 @@
+# Example recipe for building the binary version of a DKMS module
+#
+# This software is a part of ISAR.

+# Copyright (c) Siemens AG, 2021

+#
+# SPDX-License-Identifier: MIT
+
+inherit dkms-module
+
+PN .= "-${KERNEL_NAME}"
+

+#package name (without -dkms. E.g "v4l2loopback" for package "v4l2loopback-dkms")
+DKMS_PACKAGE_NAME = "v4l2loopback"
+AUTOLOAD += "v4l2loopback"
diff --git a/meta/classes/dkms-module.bbclass b/meta/classes/dkms-module.bbclass
new file mode 100644
index 0000000..9fbf4c2
--- /dev/null
+++ b/meta/classes/dkms-module.bbclass
@@ -0,0 +1,70 @@

+# This software is a part of ISAR.

+# Copyright (C) 2021 Siemens AG

+#
+# SPDX-License-Identifier: MIT
+

+inherit dpkg-raw
+
+# Build and install a kernel module that is available via a debian DKMS package.
+# As it is hard to directly build and install the package we create and distribute
+# a meta package that is independent of the kernel version.
+# In that package, we depend on the versioned prebuild kernel module package.
+#
+# To build the dkms module, we add two tasks and directly

+# use dkms to build the debian package containing the binary module

+# Then we just copy the binary-module debian package to the workdir,
+# so ISAR's do_deploy_deb picks it up.

+
+#package name (without -dkms. E.g "dpdk-kmods" for package "dpdk-kmods-dkms")

+DKMS_PACKAGE_NAME ?= ""
+AUTOLOAD ?= ""
+
+DESCRIPTION ?= "Kernel module from DKMS package for ${PN}"
+DEPENDS += "linux-headers-${KERNEL_NAME}"
+DEBIAN_DEPENDS += "${DKMS_PACKAGE_NAME}-modules,"
+DEBIAN_BUILD_DEPENDS += "linux-headers-${KERNEL_NAME}, ${DKMS_PACKAGE_NAME}-dkms,"
+

+ISAR_CROSS_COMPILE = "0"

+
+# install configuration to auto-load the modules in ${AUTOLOAD}
+do_install() {
+ # auto load the module
+ install -v -d ${D}/etc/modules-load.d
+ for module in "${AUTOLOAD}"; do
+ echo $module > ${D}/etc/modules-load.d/${PN}.conf
+ done

+}
+
+# build the binary kernel module and package as debian package (versioned)
+do_module_build() {
+ # we have to find out the module version, e.g. dpdk-kmods/0~20201113+git -k 5.10.0-3-rt-amd64/x86_64
+ REVISION=$(find ${BUILDCHROOT_DIR}/usr/src/${DKMS_PACKAGE_NAME}-* -type d -exec basename {} + | sed 's/${DKMS_PACKAGE_NAME}-//g')
+ if ! dpkg -s --root=${BUILDCHROOT_DIR} linux-headers-${KERNEL_NAME} | grep "Depends:.*linux-headers"; then
+ # custom kernels directly place their files in linux-image-KERNEL-NAME, instead
+ # of using a meta package + a versioned package with the resources
+ # The prebuild DKMS binary package depends on the versioned kernel package,
+ # but that is not available on custom kernels. Hence, we just remove the dependency.
+ bbnote "Building ${DKMS_PACKAGE_NAME} for custom kernel ${KERNEL_NAME}"

+ cp ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control ${WORKDIR}/control.dkms.orig

+ sudo sed -i 's/, linux-image-KERNEL_VERSION//' ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control
+ fi
+ # build the module for all installed kernels (should be just one)
+ sudo -E chroot ${BUILDCHROOT_DIR} dkms mkbmdeb ${DKMS_PACKAGE_NAME}/${REVISION} --all
+ DKMS_PACKAGE_VERSIONED=$(find ${BUILDCHROOT_DIR}/var/lib/dkms/${DKMS_PACKAGE_NAME}/ -name "${DKMS_PACKAGE_NAME}-modules*.deb" -exec dpkg -I {} + | grep "Package:" | awk '{print $2}')
+ if [ -z "$DKMS_PACKAGE_VERSIONED" ]; then
+ bberror "No prebuild dkms module found"
+ exit 1
+ fi
+ # restore dkms template (if any)

+ cp ${WORKDIR}/control.dkms.orig ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control || true

+}
+
+# simply copy our module from the build tree to the expected output location
+# of this recipe. Then, do_deploy_dep finds it and adds it to the
+# debian isar repo
+do_module_deploy() {

+ cp ${BUILDCHROOT_DIR}/var/lib/dkms/${DKMS_PACKAGE_NAME}/*/bmdeb/*.deb ${S}/../

+}
+
+addtask module_build after do_install_builddeps before do_dpkg_build
+addtask module_deploy after do_module_build before do_deploy_deb

diff --git a/scripts/ci_build.sh b/scripts/ci_build.sh
index adc22e4..1426569 100755
--- a/scripts/ci_build.sh
+++ b/scripts/ci_build.sh
@@ -259,6 +259,7 @@ mv ${BUILDDIR}/tmp/deploy/images/qemuamd64/isar-image-base-debian-stretch-qemuam

# Finalize with containerized images, since they remove some not-needed packages from the local.conf
sed -i -e 's/\(IMAGE_INSTALL = .*\) example-module-${KERNEL_NAME}\(.*\)/\1\2/g' conf/local.conf
+sed -i -e 's/\(IMAGE_INSTALL = .*\) example-dkms-module-${KERNEL_NAME}\(.*\)/\1\2/g' conf/local.conf
sed -i -e 's/\(IMAGE_INSTALL = .*\) enable-fsck\(.*\)/\1\2/g' conf/local.conf
bitbake $BB_ARGS $TARGETS_CONTAINERS
while [ -e bitbake.sock ]; do sleep 1; done
--
2.20.1

[Felix Moessbauer]

Hi Jan,
Hi Anton,

thanks for the review comments. These are now reflected in version 2.
Unfortunately, the v4l2loopback module does not compile on armhf.
This seems to be an upstream bug. Is there a way to disable the recipe just for this architecture?

Changes since v1:

- add example to local.conf.sample (for CI)
- disable crossbuilds
- fix copyright header

Best regards,
Felix

Felix Moessbauer (1):

Add support to build binary version of DKMS kernel modules

meta-isar/conf/local.conf.sample | 2 +-
.../example-dkms-module.bb | 14 ++++
meta/classes/dkms-module.bbclass | 70 +++++++++++++++++++
scripts/ci_build.sh | 1 +
4 files changed, 86 insertions(+), 1 deletion(-)
create mode 100644 meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb
create mode 100644 meta/classes/dkms-module.bbclass

--
2.20.1

[Jan Kiszka]

On 22.04.21 18:02, Felix Moessbauer wrote:
> Hi Jan,
> Hi Anton,
>
> thanks for the review comments. These are now reflected in version 2.
> Unfortunately, the v4l2loopback module does not compile on armhf.
> This seems to be an upstream bug. Is there a way to disable the recipe just for this architecture?
>

IMAGE_INSTALL_remove_armhf in local.conf.sample could be an option.

Jan

> Changes since v1:
>
> - add example to local.conf.sample (for CI)
> - disable crossbuilds
> - fix copyright header
>
> Best regards,
> Felix
>
> Felix Moessbauer (1):
> Add support to build binary version of DKMS kernel modules
>
> meta-isar/conf/local.conf.sample | 2 +-
> .../example-dkms-module.bb | 14 ++++
> meta/classes/dkms-module.bbclass | 70 +++++++++++++++++++
> scripts/ci_build.sh | 1 +
> 4 files changed, 86 insertions(+), 1 deletion(-)
> create mode 100644 meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb
> create mode 100644 meta/classes/dkms-module.bbclass
>

--

[Felix Moessbauer]

This patch adds support to build and install a kernel module that is available
via a debian DKMS package.
As it is hard to directly build and install the package we create and distribute
a meta package that is independent of the kernel version.
In that package, we depend on the versioned prebuild kernel module package.

To build the dkms module, we add two tasks and directly
use dkms to build the debian package containing the binary module
Then we just copy the binary-module debian package to the workdir,

Signed-off-by: Felix Moessbauer <felix.mo...@siemens.com>
---

meta-isar/conf/local.conf.sample | 5 +-
.../example-dkms-module.bb | 14 ++++
meta/classes/dkms-module.bbclass | 75 +++++++++++++++++++
scripts/ci_build.sh | 1 +
4 files changed, 94 insertions(+), 1 deletion(-)

create mode 100644 meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb
create mode 100644 meta/classes/dkms-module.bbclass

diff --git a/meta-isar/conf/local.conf.sample b/meta-isar/conf/local.conf.sample
index 77585ec..67a98d6 100644
--- a/meta-isar/conf/local.conf.sample
+++ b/meta-isar/conf/local.conf.sample
@@ -178,7 +178,10 @@ CONF_VERSION = "1"

#
# The default list of extra packages to be installed.
-IMAGE_INSTALL = "hello-isar example-raw example-module-${KERNEL_NAME} enable-fsck isar-exclude-docs samefile hello isar-disable-apt-cache cowsay example-prebuilt"
+IMAGE_INSTALL = "hello-isar example-raw example-module-${KERNEL_NAME} example-dkms-module-${KERNEL_NAME} enable-fsck isar-exclude-docs samefile hello isar-disable-apt-cache cowsay example-prebuilt"

+
+# v4l2loopback module does not build on armhf
+IMAGE_INSTALL_remove_armhf = "example-dkms-module-${KERNEL_NAME}"

#
# Enable cross-compilation support
diff --git a/meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb b/meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb

new file mode 100644

index 0000000..113f232
--- /dev/null
+++ b/meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb

@@ -0,0 +1,14 @@
+# Example recipe for building the binary version of a DKMS module
+#
+# This software is a part of ISAR.

+# Copyright (c) Siemens AG, 2021

+#
+# SPDX-License-Identifier: MIT
+
+inherit dkms-module
+
+PN .= "-${KERNEL_NAME}"
+

+#package name (without -dkms. E.g "v4l2loopback" for package "v4l2loopback-dkms")
+DKMS_PACKAGE_NAME = "v4l2loopback"
+AUTOLOAD += "v4l2loopback"
diff --git a/meta/classes/dkms-module.bbclass b/meta/classes/dkms-module.bbclass

new file mode 100644
index 0000000..f656f07
--- /dev/null
+++ b/meta/classes/dkms-module.bbclass
@@ -0,0 +1,75 @@

+# This software is a part of ISAR.

+# Copyright (C) 2021 Siemens AG

+#
+# SPDX-License-Identifier: MIT
+

+inherit dpkg-raw
+
+# Build and install a kernel module that is available via a debian DKMS package.
+# As it is hard to directly build and install the package we create and distribute
+# a meta package that is independent of the kernel version.
+# In that package, we depend on the versioned prebuild kernel module package.
+#
+# To build the dkms module, we add two tasks and directly
+# use dkms to build the debian package containing the binary module
+# Then we just copy the binary-module debian package to the workdir,
+# so ISAR's do_deploy_deb picks it up.

+
+#package name (without -dkms. E.g "dpdk-kmods" for package "dpdk-kmods-dkms")

+DKMS_PACKAGE_NAME ?= ""
+AUTOLOAD ?= ""
+
+DESCRIPTION ?= "Kernel module from DKMS package for ${PN}"
+DEPENDS += "linux-headers-${KERNEL_NAME}"
+DEBIAN_DEPENDS += "${DKMS_PACKAGE_NAME}-modules,"
+DEBIAN_BUILD_DEPENDS += "linux-headers-${KERNEL_NAME}, ${DKMS_PACKAGE_NAME}-dkms,"
+
+ISAR_CROSS_COMPILE = "0"
+
+# install configuration to auto-load the modules in ${AUTOLOAD}
+do_install() {
+ # auto load the module
+ install -v -d ${D}/etc/modules-load.d
+ for module in "${AUTOLOAD}"; do
+ echo $module > ${D}/etc/modules-load.d/${PN}.conf
+ done
+}
+
+# build the binary kernel module and package as debian package (versioned)
+do_module_build() {
+ # we have to find out the module version, e.g. dpdk-kmods/0~20201113+git -k 5.10.0-3-rt-amd64/x86_64
+ REVISION=$(find ${BUILDCHROOT_DIR}/usr/src/${DKMS_PACKAGE_NAME}-* -type d -exec basename {} + | sed 's/${DKMS_PACKAGE_NAME}-//g')

+ DKMS_ARCH=$(echo ${DISTRO_ARCH} | sed 's/amd64/x86_64/g' | sed 's/arm64/aarch64/g')

+ if ! dpkg -s --root=${BUILDCHROOT_DIR} linux-headers-${KERNEL_NAME} | grep "Depends:.*linux-headers"; then
+ # custom kernels directly place their files in linux-image-KERNEL-NAME, instead
+ # of using a meta package + a versioned package with the resources
+ # The prebuild DKMS binary package depends on the versioned kernel package,
+ # but that is not available on custom kernels. Hence, we just remove the dependency.
+ bbnote "Building ${DKMS_PACKAGE_NAME} for custom kernel ${KERNEL_NAME}"
+ cp ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control ${WORKDIR}/control.dkms.orig
+ sudo sed -i 's/, linux-image-KERNEL_VERSION//' ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control

+ KERNEL_FULLNAME=${KERNEL_NAME}
+ else
+ KERNEL_FULLNAME=$(dpkg -s --root=${BUILDCHROOT_DIR} linux-headers-${KERNEL_NAME} | grep "Depends:.*linux-headers" | sed 's/Depends: linux-headers-//g')
+ bbnote "Building for kernel $KERNEL_FULLNAME"

+ fi
+ # build the module for all installed kernels (should be just one)

+ sudo -E chroot ${BUILDCHROOT_DIR} dkms mkbmdeb ${DKMS_PACKAGE_NAME}/${REVISION} -k ${KERNEL_FULLNAME}/${DKMS_ARCH}

[Felix Moessbauer]

Hi Jan, Anton,

while playing around with various targets, I noticed that the auto-detection of the current
kernel does not work well in the chroot environments.
Instead, we now tell dkms the exact kernel version and architecture based on the debian kernel image
and the target architecture.

Changes since v2:

- do not auto-detect kernel, but extract it from the ISAR arch + kernel image name
- fix builds on ubuntu

Best regards,
Felix

Felix Moessbauer (1):
Add support to build binary version of DKMS kernel modules

meta-isar/conf/local.conf.sample | 5 +-
.../example-dkms-module.bb | 14 ++++
meta/classes/dkms-module.bbclass | 75 +++++++++++++++++++
scripts/ci_build.sh | 1 +
4 files changed, 94 insertions(+), 1 deletion(-)
create mode 100644 meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb
create mode 100644 meta/classes/dkms-module.bbclass

--
2.20.1

[Anton Mikanovich]

26.04.2021 19:16, Felix Moessbauer wrote:
> This patch adds support to build and install a kernel module that is available
> via a debian DKMS package.
> As it is hard to directly build and install the package we create and distribute
> a meta package that is independent of the kernel version.
> In that package, we depend on the versioned prebuild kernel module package.
>
> To build the dkms module, we add two tasks and directly
> use dkms to build the debian package containing the binary module
> Then we just copy the binary-module debian package to the workdir,
>
> Signed-off-by: Felix Moessbauer <felix.mo...@siemens.com>

There is an issue on building example-dkms-module-686-pae for
mc:qemui386-stretch:isar-image-base target in case of ISAR_CROSS_COMPILE
is set to 0:
>Gathering binaries...Error! No modules built for 4.9.0-15-686-pae (i386).
Please try and fix.

[Felix Moessbauer]

Hi,

this also fixes the build for i386.

Changes since v3:

- ensure that the module is build before packaging (fixes i386)
- add mapping between ISAR arch name and kernel (machine) arch

Best regards,
Felix

Felix Moessbauer (1):
Add support to build binary version of DKMS kernel modules

meta-isar/conf/local.conf.sample | 5 +-
.../example-dkms-module.bb | 14 ++++

meta/classes/dkms-module.bbclass | 76 +++++++++++++++++++
scripts/ci_build.sh | 1 +
4 files changed, 95 insertions(+), 1 deletion(-)

[Felix Moessbauer]

This patch adds support to build and install a kernel module that is available
via a debian DKMS package.
As it is hard to directly build and install the package we create and distribute
a meta package that is independent of the kernel version.
In that package, we depend on the versioned prebuild kernel module package.

To build the dkms module, we add two tasks and directly
use dkms to build the debian package containing the binary module
Then we just copy the binary-module debian package to the workdir,

Signed-off-by: Felix Moessbauer <felix.mo...@siemens.com>

---

meta-isar/conf/local.conf.sample | 5 +-
.../example-dkms-module.bb | 14 ++++
meta/classes/dkms-module.bbclass | 76 +++++++++++++++++++
scripts/ci_build.sh | 1 +
4 files changed, 95 insertions(+), 1 deletion(-)
create mode 100644 meta-isar/recipes-kernel/example-dkms-module/example-dkms-module.bb
create mode 100644 meta/classes/dkms-module.bbclass

index 0000000..283bff7
--- /dev/null
+++ b/meta/classes/dkms-module.bbclass
@@ -0,0 +1,76 @@

+ DKMS_ARCH=$(echo ${DISTRO_ARCH} | sed 's/amd64/x86_64/g' | sed 's/arm64/aarch64/g' | sed 's/i386/i686/g')

+ if ! dpkg -s --root=${BUILDCHROOT_DIR} linux-headers-${KERNEL_NAME} | grep "Depends:.*linux-headers"; then
+ # custom kernels directly place their files in linux-image-KERNEL-NAME, instead
+ # of using a meta package + a versioned package with the resources
+ # The prebuild DKMS binary package depends on the versioned kernel package,
+ # but that is not available on custom kernels. Hence, we just remove the dependency.
+ bbnote "Building ${DKMS_PACKAGE_NAME} for custom kernel ${KERNEL_NAME}"
+ cp ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control ${WORKDIR}/control.dkms.orig
+ sudo sed -i 's/, linux-image-KERNEL_VERSION//' ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control
+ KERNEL_FULLNAME=${KERNEL_NAME}
+ else
+ KERNEL_FULLNAME=$(dpkg -s --root=${BUILDCHROOT_DIR} linux-headers-${KERNEL_NAME} | grep "Depends:.*linux-headers" | sed 's/Depends: linux-headers-//g')
+ bbnote "Building for kernel $KERNEL_FULLNAME"
+ fi
+ # build the module for all installed kernels (should be just one)

+ sudo -E chroot ${BUILDCHROOT_DIR} dkms build ${DKMS_PACKAGE_NAME}/${REVISION} -k ${KERNEL_FULLNAME}/${DKMS_ARCH}

[Anton Mikanovich]

Please pay more attention to patchset versioning next time. You've
already sent v3, so this one supposed to be PATCH v4.
Also make sure the header of the cover letter to be the same as separate
patches have, linux-perf series has an issues with that.
Thank you.

[Henning Schild]

Hi Felix,

one generic question ... does this potentially also have sort of a
"apt-get update" problem?

Say we build with isar and deploy a package feed to our target, would
that target be able to update its kernel and the package ... having
both module versions installed and working depending which kernel is
booted?

Am Fri, 30 Apr 2021 16:02:52 +0200
schrieb Felix Moessbauer <felix.mo...@siemens.com>:

why do those three to += ? i would imagine a recipe using += or a class
using ?=

> ${DKMS_PACKAGE_NAME}-dkms," +
> +ISAR_CROSS_COMPILE = "0"
> +
> +# install configuration to auto-load the modules in ${AUTOLOAD}
> +do_install() {
> + # auto load the module
> + install -v -d ${D}/etc/modules-load.d
> + for module in "${AUTOLOAD}"; do
> + echo $module > ${D}/etc/modules-load.d/${PN}.conf
> + done
> +}
> +
> +# build the binary kernel module and package as debian package
> (versioned) +do_module_build() {
> + # we have to find out the module version, e.g.
> dpdk-kmods/0~20201113+git -k 5.10.0-3-rt-amd64/x86_64

switch comment to v4l?

> + REVISION=$(find
> ${BUILDCHROOT_DIR}/usr/src/${DKMS_PACKAGE_NAME}-* -type d -exec
> basename {} + | sed 's/${DKMS_PACKAGE_NAME}-//g')
> + DKMS_ARCH=$(echo ${DISTRO_ARCH} | sed 's/amd64/x86_64/g' | sed
> 's/arm64/aarch64/g' | sed 's/i386/i686/g')
> + if ! dpkg -s --root=${BUILDCHROOT_DIR}
> linux-headers-${KERNEL_NAME} | grep "Depends:.*linux-headers"; then

can be convice that first command to use a format we do not need to
parse with grep?
Along the lines of "dpkg-deb --show --showformat '${Version}'"

> + # custom kernels directly place their files in
> linux-image-KERNEL-NAME, instead
> + # of using a meta package + a versioned package with the
> resources
> + # The prebuild DKMS binary package depends on the versioned
> kernel package,
> + # but that is not available on custom kernels. Hence, we
> just remove the dependency.
> + bbnote "Building ${DKMS_PACKAGE_NAME} for custom kernel
> ${KERNEL_NAME}"
> + cp
> ${BUILDCHROOT_DIR}/etc/dkms/template-dkms-mkbmdeb/debian/control
> ${WORKDIR}/control.dkms.orig

good idea to keep that backup, but i guess if we run this task twice
because it failed inbetween, that might not work

usual solutions are "rm -rf" or [cleandirs] ... maybe that is in here
but i did not see it

Henning