[PATCH v3 0/3] Kbuild follow-up

[PATCH v3 0/3] Kbuild follow-up

[Adriaan Schmidt]

Based on the Stefan's "[PATCH] linux-module: Support emulated module build
with cross-compiled kernel", and on the result of staring at dependency
graphs with Jan, this mainly addresses corner cases of the refactored
kbuild packaging when cross-compiling.

I've tested

- cross-compiled custom kernel and cross module build
- cross-compiled custom kernel and emulated module build
- distro kernel and emulated module build

Let me know if one of your use-cases is still missing.

Also including some fixups brought up in recent reviews on the ML.

Adriaan

changes since v2:
- removed a forgotten line of testing code

changes since v1:
- always use linux-kbuild-native as build dependency, even for emulated
  builds, because the multiarch logic will select the correct package


*** BLURB HERE ***

Adriaan Schmidt (3):
  module.inc: fix kbuild dependency
  linux-custom: use to_boolean when checking ISAR_CROSS_COMPILE
  kbuildtarget.bbclass: add missing license header

 meta/recipes-kernel/linux-module/module.inc            | 3 ++-
 meta/recipes-kernel/linux/classes/kbuildtarget.bbclass | 5 +++++
 meta/recipes-kernel/linux/linux-custom.inc             | 5 +----
 meta/recipes-kernel/linux/linux-distro.bb              | 1 +
 4 files changed, 9 insertions(+), 5 deletions(-)

-- 
2.39.2

[PATCH v3 1/3] module.inc: fix kbuild dependency

[Adriaan Schmidt]

This achieves two things:

* Module builds explicitly depend on linux-kbuild-* as build dependency.
  Previously we only had an implicit RDEPENDS in linux-custom, which is
  not sufficient. For linux-distro, this means we need to PROVIDE linux-kbuild.
* Remove the unconditional building of native kbuild when it is
  not needed, i.e. when we're not actually cross-building a module

Signed-off-by: Adriaan Schmidt <adriaan.schmidt@siemens.com>
---
 meta/recipes-kernel/linux-module/module.inc | 3 ++-
 meta/recipes-kernel/linux/linux-custom.inc  | 3 ---
 meta/recipes-kernel/linux/linux-distro.bb   | 1 +
 3 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/meta/recipes-kernel/linux-module/module.inc b/meta/recipes-kernel/linux-module/module.inc
index eddbf177..1cca9cfb 100644
--- a/meta/recipes-kernel/linux-module/module.inc
+++ b/meta/recipes-kernel/linux-module/module.inc
@@ -17,7 +17,8 @@ PN .= "-${KERNEL_NAME}"
 
 KERNEL_IMAGE_PKG ??= "linux-image-${KERNEL_NAME}"
 KERNEL_HEADERS_PKG ??= "linux-headers-${KERNEL_NAME}"
-DEPENDS += "${KERNEL_HEADERS_PKG}"
+KERNEL_KBUILD_PKG ??= "linux-kbuild-${KERNEL_NAME}"
+DEPENDS += "${KERNEL_HEADERS_PKG} ${KERNEL_KBUILD_PKG}-native"
 DEBIAN_BUILD_DEPENDS = "${KERNEL_HEADERS_PKG}"
 
 SIGNATURE_KEYFILE ??= ""
diff --git a/meta/recipes-kernel/linux/linux-custom.inc b/meta/recipes-kernel/linux/linux-custom.inc
index 0d222332..35c61187 100644
--- a/meta/recipes-kernel/linux/linux-custom.inc
+++ b/meta/recipes-kernel/linux/linux-custom.inc
@@ -148,9 +148,6 @@ PROVIDES += "${RECIPE_PROVIDES}"
 # Append build profiles
 DEB_BUILD_PROFILES += "${BUILD_PROFILES}"
 
-# Add dependency to build -kbuildtarget and -native automatically
-RDEPENDS:append:cross-profile = " ${BPN}-native"
-
 def get_kernel_arch(d):
     distro_arch = d.getVar("DISTRO_ARCH")
     if distro_arch in ["amd64", "i386"]:
diff --git a/meta/recipes-kernel/linux/linux-distro.bb b/meta/recipes-kernel/linux/linux-distro.bb
index bc43528c..13b8dc7e 100644
--- a/meta/recipes-kernel/linux/linux-distro.bb
+++ b/meta/recipes-kernel/linux/linux-distro.bb
@@ -10,6 +10,7 @@ python() {
     for kernel in distro_kernels.split():
         d.appendVar('PROVIDES', ' linux-image-' + kernel)
         d.appendVar('PROVIDES', ' linux-headers-' + kernel)
+        d.appendVar('PROVIDES', ' linux-kbuild-' + kernel)
     if d.getVar('KERNEL_IMAGE_PKG'):
         d.appendVar('PROVIDES', ' ' + d.getVar('KERNEL_IMAGE_PKG'))
     if d.getVar('KERNEL_HEADERS_PKG'):
-- 
2.39.2

[PATCH v3 2/3] linux-custom: use to_boolean when checking ISAR_CROSS_COMPILE

[Adriaan Schmidt]

we've changed style/convention in Isar sometime during the review of the
kbuild series, and this was missed.

Signed-off-by: Adriaan Schmidt <adriaan.schmidt@siemens.com>
---
 meta/recipes-kernel/linux/linux-custom.inc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/meta/recipes-kernel/linux/linux-custom.inc b/meta/recipes-kernel/linux/linux-custom.inc
index 35c61187..53516ef3 100644
--- a/meta/recipes-kernel/linux/linux-custom.inc
+++ b/meta/recipes-kernel/linux/linux-custom.inc
@@ -97,7 +97,7 @@ KERNEL_NAME_PROVIDED ?= "${@ d.getVar('BPN').partition('linux-')[2]}"
 
 # Determine cross-profile override
 python() {
-    if d.getVar("DISTRO_ARCH") != d.getVar("HOST_ARCH") and d.getVar("ISAR_CROSS_COMPILE", True) == "1" and "class-native" not in d.getVar("OVERRIDES", True).split(":"):
+    if d.getVar("DISTRO_ARCH") != d.getVar("HOST_ARCH") and bb.utils.to_boolean(d.getVar("ISAR_CROSS_COMPILE")) and "class-native" not in d.getVar("OVERRIDES", True).split(":"):
         d.appendVar("OVERRIDES", ":cross-profile")
 }
 
-- 
2.39.2

[PATCH v3 3/3] kbuildtarget.bbclass: add missing license header

[Adriaan Schmidt]

Signed-off-by: Adriaan Schmidt <adriaan.schmidt@siemens.com>
---
 meta/recipes-kernel/linux/classes/kbuildtarget.bbclass | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/meta/recipes-kernel/linux/classes/kbuildtarget.bbclass b/meta/recipes-kernel/linux/classes/kbuildtarget.bbclass
index 26369861..648825e4 100644
--- a/meta/recipes-kernel/linux/classes/kbuildtarget.bbclass
+++ b/meta/recipes-kernel/linux/classes/kbuildtarget.bbclass
@@ -1,3 +1,8 @@
+# This software is a part of ISAR.
+# Copyright (C) 2024 Siemens AG
+#
+# SPDX-License-Identifier: MIT
+
 python kbuildtarget_virtclass_handler() {
     pn = e.data.getVar('PN')
     if pn.endswith('-kbuildtarget'):
-- 
2.39.2

Re: [PATCH v3 1/3] module.inc: fix kbuild dependency

[Jan Kiszka]

On 13.05.24 06:17, Adriaan Schmidt wrote:
> This achieves two things:
> 
> * Module builds explicitly depend on linux-kbuild-* as build dependency.
>   Previously we only had an implicit RDEPENDS in linux-custom, which is
>   not sufficient. For linux-distro, this means we need to PROVIDE linux-kbuild.
> * Remove the unconditional building of native kbuild when it is
>   not needed, i.e. when we're not actually cross-building a module
> 
> Signed-off-by: Adriaan Schmidt <adriaan.schmidt@siemens.com>
> ---
>  meta/recipes-kernel/linux-module/module.inc | 3 ++-
>  meta/recipes-kernel/linux/linux-custom.inc  | 3 ---
>  meta/recipes-kernel/linux/linux-distro.bb   | 1 +
>  3 files changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/meta/recipes-kernel/linux-module/module.inc b/meta/recipes-kernel/linux-module/module.inc
> index eddbf177..1cca9cfb 100644
> --- a/meta/recipes-kernel/linux-module/module.inc
> +++ b/meta/recipes-kernel/linux-module/module.inc
> @@ -17,7 +17,8 @@ PN .= "-${KERNEL_NAME}"
>  
>  KERNEL_IMAGE_PKG ??= "linux-image-${KERNEL_NAME}"
>  KERNEL_HEADERS_PKG ??= "linux-headers-${KERNEL_NAME}"
> -DEPENDS += "${KERNEL_HEADERS_PKG}"
> +KERNEL_KBUILD_PKG ??= "linux-kbuild-${KERNEL_NAME}"
> +DEPENDS += "${KERNEL_HEADERS_PKG} ${KERNEL_KBUILD_PKG}-native"
>  DEBIAN_BUILD_DEPENDS = "${KERNEL_HEADERS_PKG}"
>  
>  SIGNATURE_KEYFILE ??= ""
> diff --git a/meta/recipes-kernel/linux/linux-custom.inc b/meta/recipes-kernel/linux/linux-custom.inc
> index 0d222332..35c61187 100644
> --- a/meta/recipes-kernel/linux/linux-custom.inc
> +++ b/meta/recipes-kernel/linux/linux-custom.inc
> @@ -148,9 +148,6 @@ PROVIDES += "${RECIPE_PROVIDES}"
>  # Append build profiles
>  DEB_BUILD_PROFILES += "${BUILD_PROFILES}"
>  
> -# Add dependency to build -kbuildtarget and -native automatically
> -RDEPENDS:append:cross-profile = " ${BPN}-native"
> -
>  def get_kernel_arch(d):
>      distro_arch = d.getVar("DISTRO_ARCH")
>      if distro_arch in ["amd64", "i386"]:
> diff --git a/meta/recipes-kernel/linux/linux-distro.bb b/meta/recipes-kernel/linux/linux-distro.bb
> index bc43528c..13b8dc7e 100644
> --- a/meta/recipes-kernel/linux/linux-distro.bb
> +++ b/meta/recipes-kernel/linux/linux-distro.bb
> @@ -10,6 +10,7 @@ python() {
>      for kernel in distro_kernels.split():
>          d.appendVar('PROVIDES', ' linux-image-' + kernel)
>          d.appendVar('PROVIDES', ' linux-headers-' + kernel)
> +        d.appendVar('PROVIDES', ' linux-kbuild-' + kernel)
>      if d.getVar('KERNEL_IMAGE_PKG'):
>          d.appendVar('PROVIDES', ' ' + d.getVar('KERNEL_IMAGE_PKG'))
>      if d.getVar('KERNEL_HEADERS_PKG'):

There is another change coming with this: In order to install
linux-headers into your target image, you now need to explicitly depend
on linux-${KERNEL_NAME}-kbuildtarget in the image recipe.
linux-headers-${KERNEL_NAME} will not pull the kbuildtarget, and the
latter is not auto-built anymore.

I'm testing some idea (some may call it hack) to resolve that by moving
the linux-headers provider to kbuildtarget and native and then let those
two depend on the base recipe. Not straightforward, but it seems to work.

Jan

-- 
Siemens AG, Technology
Linux Expert Center

Re: [PATCH v3 1/3] module.inc: fix kbuild dependency

[Jan Kiszka]

On 13.05.24 07:24, Jan Kiszka wrote:
> On 13.05.24 06:17, Adriaan Schmidt wrote:
>> This achieves two things:
>>
>> * Module builds explicitly depend on linux-kbuild-* as build dependency.
>>   Previously we only had an implicit RDEPENDS in linux-custom, which is
>>   not sufficient. For linux-distro, this means we need to PROVIDE linux-kbuild.
>> * Remove the unconditional building of native kbuild when it is
>>   not needed, i.e. when we're not actually cross-building a module
>>
>> Signed-off-by: Adriaan Schmidt <adriaan.schmidt@siemens.com>
>> ---
>>  meta/recipes-kernel/linux-module/module.inc | 3 ++-
>>  meta/recipes-kernel/linux/linux-custom.inc  | 3 ---
>>  meta/recipes-kernel/linux/linux-distro.bb   | 1 +
>>  3 files changed, 3 insertions(+), 4 deletions(-)
>>
>> diff --git a/meta/recipes-kernel/linux-module/module.inc b/meta/recipes-kernel/linux-module/module.inc
>> index eddbf177..1cca9cfb 100644
>> --- a/meta/recipes-kernel/linux-module/module.inc
>> +++ b/meta/recipes-kernel/linux-module/module.inc
>> @@ -17,7 +17,8 @@ PN .= "-${KERNEL_NAME}"
>>  
>>  KERNEL_IMAGE_PKG ??= "linux-image-${KERNEL_NAME}"
>>  KERNEL_HEADERS_PKG ??= "linux-headers-${KERNEL_NAME}"
>> -DEPENDS += "${KERNEL_HEADERS_PKG}"
>> +KERNEL_KBUILD_PKG ??= "linux-kbuild-${KERNEL_NAME}"
>> +DEPENDS += "${KERNEL_HEADERS_PKG} ${KERNEL_KBUILD_PKG}-native"
>>  DEBIAN_BUILD_DEPENDS = "${KERNEL_HEADERS_PKG}"
>>  
>>  SIGNATURE_KEYFILE ??= ""
>> diff --git a/meta/recipes-kernel/linux/linux-custom.inc b/meta/recipes-kernel/linux/linux-custom.inc
>> index 0d222332..35c61187 100644
>> --- a/meta/recipes-kernel/linux/linux-custom.inc
>> +++ b/meta/recipes-kernel/linux/linux-custom.inc
>> @@ -148,9 +148,6 @@ PROVIDES += "${RECIPE_PROVIDES}"
>>  # Append build profiles
>>  DEB_BUILD_PROFILES += "${BUILD_PROFILES}"
>>  
>> -# Add dependency to build -kbuildtarget and -native automatically
>> -RDEPENDS:append:cross-profile = " ${BPN}-native"
>> -
>>  def get_kernel_arch(d):
>>      distro_arch = d.getVar("DISTRO_ARCH")
>>      if distro_arch in ["amd64", "i386"]:
>> diff --git a/meta/recipes-kernel/linux/linux-distro.bb b/meta/recipes-kernel/linux/linux-distro.bb
>> index bc43528c..13b8dc7e 100644
>> --- a/meta/recipes-kernel/linux/linux-distro.bb
>> +++ b/meta/recipes-kernel/linux/linux-distro.bb
>> @@ -10,6 +10,7 @@ python() {
>>      for kernel in distro_kernels.split():
>>          d.appendVar('PROVIDES', ' linux-image-' + kernel)
>>          d.appendVar('PROVIDES', ' linux-headers-' + kernel)
>> +        d.appendVar('PROVIDES', ' linux-kbuild-' + kernel)
>>      if d.getVar('KERNEL_IMAGE_PKG'):
>>          d.appendVar('PROVIDES', ' ' + d.getVar('KERNEL_IMAGE_PKG'))
>>      if d.getVar('KERNEL_HEADERS_PKG'):
> 
> There is another change coming with this: In order to install
> linux-headers into your target image, you now need to explicitly depend
> on linux-${KERNEL_NAME}-kbuildtarget in the image recipe.
> linux-headers-${KERNEL_NAME} will not pull the kbuildtarget, and the
> latter is not auto-built anymore.
> 
> I'm testing some idea (some may call it hack) to resolve that by moving
> the linux-headers provider to kbuildtarget and native and then let those
> two depend on the base recipe. Not straightforward, but it seems to work.
> 

The following changes on top of the this patch is apparently working 
fine, and you can simply do

IMAGE_INSTALL += "linux-headers-${KERNEL_NAME}"

again.

diff --git a/meta/recipes-kernel/linux-module/module.inc b/meta/recipes-kernel/linux-module/module.inc
index 1cca9cfb..229e6a5c 100644
--- a/meta/recipes-kernel/linux-module/module.inc
+++ b/meta/recipes-kernel/linux-module/module.inc
@@ -17,8 +17,7 @@ PN .= "-${KERNEL_NAME}"
 
 KERNEL_IMAGE_PKG ??= "linux-image-${KERNEL_NAME}"
 KERNEL_HEADERS_PKG ??= "linux-headers-${KERNEL_NAME}"
-KERNEL_KBUILD_PKG ??= "linux-kbuild-${KERNEL_NAME}"
-DEPENDS += "${KERNEL_HEADERS_PKG} ${KERNEL_KBUILD_PKG}-native"
+DEPENDS += "${KERNEL_HEADERS_PKG}-native"
 DEBIAN_BUILD_DEPENDS = "${KERNEL_HEADERS_PKG}"
 
 SIGNATURE_KEYFILE ??= ""
diff --git a/meta/recipes-kernel/linux/linux-custom.inc b/meta/recipes-kernel/linux/linux-custom.inc
index af3504dd..00b169bc 100644
--- a/meta/recipes-kernel/linux/linux-custom.inc
+++ b/meta/recipes-kernel/linux/linux-custom.inc
@@ -113,11 +113,19 @@ BUILD_PROFILES:cross-profile = "kernel"
 
 # -native: kbuild package for host
 BUILD_PROFILES:class-native = "kbuild"
-RECIPE_PROVIDES:class-native = "linux-kbuild-${KERNEL_NAME_PROVIDED}-native"
+RECIPE_PROVIDES:class-native = " \
+    linux-headers-${KERNEL_NAME_PROVIDED}-native \
+    linux-kbuild-${KERNEL_NAME_PROVIDED}-native"
+# Use pseudo target. We cannot use ${BPN} because it will be auto-extended
+# with -native by multiarch.bbclass.
+RDEPENDS:class-native = "${BPN}-pseudo-native"
 
 # -kbuildtarget: kbuild package for target, enforcing non-cross-build
 BUILD_PROFILES:class-kbuildtarget = "kbuild"
-RECIPE_PROVIDES:class-kbuildtarget = "linux-kbuild-${KERNEL_NAME_PROVIDED}"
+RECIPE_PROVIDES:class-kbuildtarget = " \
+    linux-headers-${KERNEL_NAME_PROVIDED} \
+    linux-kbuild-${KERNEL_NAME_PROVIDED}"
+RDEPENDS:class-kbuildtarget = "${BPN}"
 ISAR_CROSS_COMPILE:class-kbuildtarget = "0"
 
 # Make bitbake know we will be producing linux-image and linux-headers packages
@@ -125,15 +133,21 @@ ISAR_CROSS_COMPILE:class-kbuildtarget = "0"
 RECIPE_PROVIDES = " \
     linux-image-${KERNEL_NAME_PROVIDED} \
     linux-headers-${KERNEL_NAME_PROVIDED} \
+    linux-headers-${KERNEL_NAME_PROVIDED}-native \
     linux-libc-dev \
     linux-libc-dev-${DISTRO_ARCH}-cross \
     linux-image-${KERNEL_NAME_PROVIDED}-dbg \
     linux-kbuild-${KERNEL_NAME_PROVIDED} \
+    ${BPN}-pseudo-native \
 "
 # When cross-profile is active:
-# kbuild package is provided by -native or -kbuildtarget variant
-# Otherwise it's provided by the default variant
-RECIPE_PROVIDES:remove:cross-profile = "linux-kbuild-${KERNEL_NAME_PROVIDED}"
+# kbuild package is provided by -native or -kbuildtarget variant. Also headers
+# provisioning moves over to ensure those variants are pulled, although the
+# package itself is still built by the base recipe.
+RECIPE_PROVIDES:remove:cross-profile = " \
+    linux-headers-${KERNEL_NAME_PROVIDED} \
+    linux-headers-${KERNEL_NAME_PROVIDED}-native \
+    linux-kbuild-${KERNEL_NAME_PROVIDED}"
 
 # Append headers depends
 HEADERS_DEPENDS = ", linux-kbuild-${KERNEL_NAME_PROVIDED} | linux-kbuild-${KERNEL_NAME_PROVIDED}-${DISTRO_ARCH}-cross"


Jan

-- 
Siemens AG, Technology
Linux Expert Center

Re: [PATCH v3 2/3] linux-custom: use to_boolean when checking ISAR_CROSS_COMPILE

[Koch, Stefan]

This is already included in:
[PATCH] linux-module: Support emulated module build with cross-compiled
kernel

On Mon, 2024-05-13 at 06:17 +0200, Adriaan Schmidt wrote:
> we've changed style/convention in Isar sometime during the review of
> the
> kbuild series, and this was missed.
> 
> Signed-off-by: Adriaan Schmidt <adriaan.schmidt@siemens.com>
> ---
>  meta/recipes-kernel/linux/linux-custom.inc | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/meta/recipes-kernel/linux/linux-custom.inc
> b/meta/recipes-kernel/linux/linux-custom.inc
> index 35c61187..53516ef3 100644
> --- a/meta/recipes-kernel/linux/linux-custom.inc
> +++ b/meta/recipes-kernel/linux/linux-custom.inc
> @@ -97,7 +97,7 @@ KERNEL_NAME_PROVIDED ?= "${@
> d.getVar('BPN').partition('linux-')[2]}"
>  
>  # Determine cross-profile override
>  python() {
> -    if d.getVar("DISTRO_ARCH") != d.getVar("HOST_ARCH") and
> d.getVar("ISAR_CROSS_COMPILE", True) == "1" and "class-native" not in
> d.getVar("OVERRIDES", True).split(":"):
> +    if d.getVar("DISTRO_ARCH") != d.getVar("HOST_ARCH") and
> bb.utils.to_boolean(d.getVar("ISAR_CROSS_COMPILE")) and "class-
> native" not in d.getVar("OVERRIDES", True).split(":"):
>          d.appendVar("OVERRIDES", ":cross-profile")
>  }
>  

-- 
Stefan Koch
Siemens AG
www.siemens.com

Re: [PATCH v3 2/3] linux-custom: use to_boolean when checking ISAR_CROSS_COMPILE

[Koch, Stefan]

Good improvement, when this similar cross-profile OVERRIDE is not
needed anymore for module.inc

On Mon, 2024-05-13 at 06:17 +0200, Adriaan Schmidt wrote:
> we've changed style/convention in Isar sometime during the review of
> the
> kbuild series, and this was missed.
> 
> Signed-off-by: Adriaan Schmidt <adriaan.schmidt@siemens.com>
> ---
>  meta/recipes-kernel/linux/linux-custom.inc | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/meta/recipes-kernel/linux/linux-custom.inc
> b/meta/recipes-kernel/linux/linux-custom.inc
> index 35c61187..53516ef3 100644
> --- a/meta/recipes-kernel/linux/linux-custom.inc
> +++ b/meta/recipes-kernel/linux/linux-custom.inc
> @@ -97,7 +97,7 @@ KERNEL_NAME_PROVIDED ?= "${@
> d.getVar('BPN').partition('linux-')[2]}"
>  
>  # Determine cross-profile override
>  python() {
> -    if d.getVar("DISTRO_ARCH") != d.getVar("HOST_ARCH") and
> d.getVar("ISAR_CROSS_COMPILE", True) == "1" and "class-native" not in
> d.getVar("OVERRIDES", True).split(":"):
> +    if d.getVar("DISTRO_ARCH") != d.getVar("HOST_ARCH") and
> bb.utils.to_boolean(d.getVar("ISAR_CROSS_COMPILE")) and "class-
> native" not in d.getVar("OVERRIDES", True).split(":"):
>          d.appendVar("OVERRIDES", ":cross-profile")
>  }
>  

-- 
Stefan Koch
Siemens AG
www.siemens.com