[PATCH 1/3] kern-tools-native: update to support modular kernel builds

[PATCH 1/3] kern-tools-native: update to support modular kernel builds

[Mikko Rapeli]

After this update scc tool can compile options as modules
conditionally without duplicating config fragments when
the options contain a comment like:

CONFIG_LEDS_GPIO=y # OVERRIDE:$MODULE_OR_Y

Then "scc -DMODULE_OR_Y=m" converts these into

CONFIG_LEDS_GPIO=m

Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
---
 meta/recipes-kernel/kern-tools/kern-tools-native_git.bb | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/meta/recipes-kernel/kern-tools/kern-tools-native_git.bb b/meta/recipes-kernel/kern-tools/kern-tools-native_git.bb
index 6dd19f1f09..20b1bcaf37 100644
--- a/meta/recipes-kernel/kern-tools/kern-tools-native_git.bb
+++ b/meta/recipes-kernel/kern-tools/kern-tools-native_git.bb
@@ -11,7 +11,7 @@ LIC_FILES_CHKSUM = "\
 
 DEPENDS += "git-replacement-native"
 
-SRCREV = "c8c1f17867d0cc7d04be225ba4901f2373428be2"
+SRCREV = "fe67c98d2e9b74af44d0c4b660fa18e3a95e7edd"
 PV = "0.3+git"
 
 inherit native
-- 
2.43.0

[PATCH 2/3] kernel-yocto.bbclass: support modular kernel configs

[Mikko Rapeli]

Compile many kernel drivers as modules when recipe sets

MODULAR_KERNEL = "true"

This likely requires support for initramfs which includes
kernel modules needed to mount the rootfs.

SCC_OPTS can be used to add arguments to scc kernel config
generation call.

Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
---
 meta/classes-recipe/kernel-yocto.bbclass | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/meta/classes-recipe/kernel-yocto.bbclass b/meta/classes-recipe/kernel-yocto.bbclass
index cef6b9ec3f..f98720bcec 100644
--- a/meta/classes-recipe/kernel-yocto.bbclass
+++ b/meta/classes-recipe/kernel-yocto.bbclass
@@ -26,6 +26,12 @@ KCONF_BSP_AUDIT_LEVEL ?= "0"
 KMETA_AUDIT ?= "yes"
 KMETA_AUDIT_WERROR ?= ""
 
+# most drivers as built in (default), or as modules
+MODULAR_KERNEL = "false"
+
+# options to scc
+SCC_OPTS ?= "${@bb.utils.contains('MODULAR_KERNEL', 'true', '-DMODULE_OR_Y=m', '', d)}"
+
 # returns local (absolute) path names for all valid patches in the
 # src_uri
 def find_patches(d,subdir):
@@ -298,7 +304,7 @@ do_kernel_metadata() {
 		elements="`echo -n ${bsp_definition} $sccs_defconfig ${sccs} ${patches} $KERNEL_FEATURES_FINAL`"
 		if [ -n "${elements}" ]; then
 			echo "${bsp_definition}" > ${S}/${meta_dir}/bsp_definition
-			scc --force -o ${S}/${meta_dir}:cfg,merge,meta ${includes} $sccs_defconfig $bsp_definition $sccs $patches $KERNEL_FEATURES_FINAL
+			scc ${SCC_OPTS} --force -o ${S}/${meta_dir}:cfg,merge,meta ${includes} $sccs_defconfig $bsp_definition $sccs $patches $KERNEL_FEATURES_FINAL
 			if [ $? -ne 0 ]; then
 				bbfatal_log "Could not generate configuration queue for ${KMACHINE}."
 			fi
-- 
2.43.0

[PATCH 3/3] linux-yocto: build modular kernel on genericarm64

[Mikko Rapeli]

genericarm64 inteds to support many devices which are not even
know at compile time and uses initramfs by default. Thus many
drivers can be build as modules to reduce kernel binary size
and boot time.

Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
---
 meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend b/meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend
index 831cb556be..cda7fef449 100644
--- a/meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend
+++ b/meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend
@@ -9,3 +9,5 @@ KMACHINE:genericx86-64 ?= "common-pc-64"
 
 FILESEXTRAPATHS:prepend:genericarm64 := "${THISDIR}/files:"
 SRC_URI:append:genericarm64 = " file://0001-Revert-serial-8250_omap-Drop-pm_runtime_irq_safe.patch"
+
+MODULAR_KERNEL:genericarm64 = "true"
-- 
2.43.0

Re: [poky] [PATCH 2/3] kernel-yocto.bbclass: support modular kernel configs

[Bruce Ashfield]

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I already have patches for this, and they have not been sent on purpose.

Please do not apply this patch, consider this a nack.

Bruce

On Wed, Apr 23, 2025 at 4:03 AM Mikko Rapeli via lists.yoctoproject.org
<mikko.rapeli=linaro.org@lists.yoctoproject.org> wrote:

> Compile many kernel drivers as modules when recipe sets
>
> MODULAR_KERNEL = "true"
>
> This likely requires support for initramfs which includes
> kernel modules needed to mount the rootfs.
>
> SCC_OPTS can be used to add arguments to scc kernel config
> generation call.
>
> Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
> ---
>  meta/classes-recipe/kernel-yocto.bbclass | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/meta/classes-recipe/kernel-yocto.bbclass
> b/meta/classes-recipe/kernel-yocto.bbclass
> index cef6b9ec3f..f98720bcec 100644
> --- a/meta/classes-recipe/kernel-yocto.bbclass
> +++ b/meta/classes-recipe/kernel-yocto.bbclass
> @@ -26,6 +26,12 @@ KCONF_BSP_AUDIT_LEVEL ?= "0"
>  KMETA_AUDIT ?= "yes"
>  KMETA_AUDIT_WERROR ?= ""
>
> +# most drivers as built in (default), or as modules
> +MODULAR_KERNEL = "false"
> +
> +# options to scc
> +SCC_OPTS ?= "${@bb.utils.contains('MODULAR_KERNEL', 'true',
> '-DMODULE_OR_Y=m', '', d)}"
> +
>  # returns local (absolute) path names for all valid patches in the
>  # src_uri
>  def find_patches(d,subdir):
> @@ -298,7 +304,7 @@ do_kernel_metadata() {
>                 elements="`echo -n ${bsp_definition} $sccs_defconfig
> ${sccs} ${patches} $KERNEL_FEATURES_FINAL`"
>                 if [ -n "${elements}" ]; then
>                         echo "${bsp_definition}" >
> ${S}/${meta_dir}/bsp_definition
> -                       scc --force -o ${S}/${meta_dir}:cfg,merge,meta
> ${includes} $sccs_defconfig $bsp_definition $sccs $patches
> $KERNEL_FEATURES_FINAL
> +                       scc ${SCC_OPTS} --force -o
> ${S}/${meta_dir}:cfg,merge,meta ${includes} $sccs_defconfig $bsp_definition
> $sccs $patches $KERNEL_FEATURES_FINAL
>                         if [ $? -ne 0 ]; then
>                                 bbfatal_log "Could not generate
> configuration queue for ${KMACHINE}."
>                         fi
> --
> 2.43.0
>
>
> -=-=-=-=-=-=-=-=-=-=-=-
> Links: You receive all messages sent to this group.
> View/Reply Online (#13599):
> https://lists.yoctoproject.org/g/poky/message/13599
> Mute This Topic: https://lists.yoctoproject.org/mt/112410521/1050810
> Group Owner: poky+owner@lists.yoctoproject.org
> Unsubscribe: https://lists.yoctoproject.org/g/poky/unsub [
> bruce.ashfield@gmail.com]
> -=-=-=-=-=-=-=-=-=-=-=-
>
>

-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

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Re: [poky] [PATCH 1/3] kern-tools-native: update to support modular kernel builds

[Bruce Ashfield]

[-- Attachment #1: Type: text/plain, Size: 1868 bytes --]

Do not apply this patch.

I have queued updates for this support, and again, they have not been sent
on purpose.

nack.

Bruce

On Wed, Apr 23, 2025 at 4:03 AM Mikko Rapeli via lists.yoctoproject.org
<mikko.rapeli=linaro.org@lists.yoctoproject.org> wrote:

> After this update scc tool can compile options as modules
> conditionally without duplicating config fragments when
> the options contain a comment like:
>
> CONFIG_LEDS_GPIO=y # OVERRIDE:$MODULE_OR_Y
>
> Then "scc -DMODULE_OR_Y=m" converts these into
>
> CONFIG_LEDS_GPIO=m
>
> Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
> ---
>  meta/recipes-kernel/kern-tools/kern-tools-native_git.bb | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/meta/recipes-kernel/kern-tools/kern-tools-native_git.bb
> b/meta/recipes-kernel/kern-tools/kern-tools-native_git.bb
> index 6dd19f1f09..20b1bcaf37 100644
> --- a/meta/recipes-kernel/kern-tools/kern-tools-native_git.bb
> +++ b/meta/recipes-kernel/kern-tools/kern-tools-native_git.bb
> @@ -11,7 +11,7 @@ LIC_FILES_CHKSUM = "\
>
>  DEPENDS += "git-replacement-native"
>
> -SRCREV = "c8c1f17867d0cc7d04be225ba4901f2373428be2"
> +SRCREV = "fe67c98d2e9b74af44d0c4b660fa18e3a95e7edd"
>  PV = "0.3+git"
>
>  inherit native
> --
> 2.43.0
>
>
> -=-=-=-=-=-=-=-=-=-=-=-
> Links: You receive all messages sent to this group.
> View/Reply Online (#13598):
> https://lists.yoctoproject.org/g/poky/message/13598
> Mute This Topic: https://lists.yoctoproject.org/mt/112396089/1050810
> Group Owner: poky+owner@lists.yoctoproject.org
> Unsubscribe: https://lists.yoctoproject.org/g/poky/unsub [
> bruce.ashfield@gmail.com]
> -=-=-=-=-=-=-=-=-=-=-=-
>
>

-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

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Re: [OE-core] [PATCH 3/3] linux-yocto: build modular kernel on genericarm64

[Bruce Ashfield]

[-- Attachment #1: Type: text/plain, Size: 1851 bytes --]

This is not the variable we'll be using for this, so again, do not apply
this patch.

Bruce

On Wed, Apr 23, 2025 at 4:03 AM Mikko Rapeli via lists.openembedded.org
<mikko.rapeli=linaro.org@lists.openembedded.org> wrote:

> genericarm64 inteds to support many devices which are not even
> know at compile time and uses initramfs by default. Thus many
> drivers can be build as modules to reduce kernel binary size
> and boot time.
>
> Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
> ---
>  meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend
> b/meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend
> index 831cb556be..cda7fef449 100644
> --- a/meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend
> +++ b/meta-yocto-bsp/recipes-kernel/linux/linux-yocto_6.12.bbappend
> @@ -9,3 +9,5 @@ KMACHINE:genericx86-64 ?= "common-pc-64"
>
>  FILESEXTRAPATHS:prepend:genericarm64 := "${THISDIR}/files:"
>  SRC_URI:append:genericarm64 = "
> file://0001-Revert-serial-8250_omap-Drop-pm_runtime_irq_safe.patch"
> +
> +MODULAR_KERNEL:genericarm64 = "true"
> --
> 2.43.0
>
>
> -=-=-=-=-=-=-=-=-=-=-=-
> Links: You receive all messages sent to this group.
> View/Reply Online (#215266):
> https://lists.openembedded.org/g/openembedded-core/message/215266
> Mute This Topic: https://lists.openembedded.org/mt/112410523/1050810
> Group Owner: openembedded-core+owner@lists.openembedded.org
> Unsubscribe: https://lists.openembedded.org/g/openembedded-core/unsub [
> bruce.ashfield@gmail.com]
> -=-=-=-=-=-=-=-=-=-=-=-
>
>

-- 
- Thou shalt not follow the NULL pointer, for chaos and madness await thee
at its end
- "Use the force Harry" - Gandalf, Star Trek II

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Re: [poky] [PATCH 2/3] kernel-yocto.bbclass: support modular kernel configs

[Mikko Rapeli]

Hi,

On Wed, Apr 23, 2025 at 08:30:50AM -0400, Bruce Ashfield wrote:
> I already have patches for this, and they have not been sent on purpose.
> 
> Please do not apply this patch, consider this a nack.

Ok, no worries.

If you have the draft patches somewhere I can try them out on genericarm64
builds and test on a few devices, if that helps.

genericarm64 core-image-initramfs-boot is exceeding size limits currently
so I wanted to publish what I had already:

https://bugzilla.yoctoproject.org/show_bug.cgi?id=15833

Cheers,

-Mikko