[Buildroot] [PATCH] linux: add an option to install kernel headers into staging

[Buildroot] [PATCH] linux: add an option to install kernel headers into staging

[Nicolas Serafini]

The kernel headers are installed into /usr/src/linux-headers-version
of the staging folder.

These headers can be used, for example, by a post build script to
install or update some new headers from the kernel in /usr/include of
the staging.

Signed-off-by: Nicolas Serafini <nicolas.serafini@sensefly.com>
---
 linux/Config.in | 6 ++++++
 linux/linux.mk  | 9 +++++++++
 2 files changed, 15 insertions(+)

diff --git a/linux/Config.in b/linux/Config.in
index fa3232f..dd97211 100644
--- a/linux/Config.in
+++ b/linux/Config.in
@@ -354,6 +354,12 @@ config BR2_LINUX_KERNEL_INSTALL_TARGET
 	  /boot if DTBs have been generated by the kernel build
 	  process.
 
+config BR2_LINUX_KERNEL_INSTALL_HEADERS
+	bool "Install kernel headers to staging"
+	help
+	  Select this option to have the kernel headers installed to
+	  staging in /usr/src/linux-headers-version folder.
+
 # Linux extensions
 source "linux/Config.ext.in"
 
diff --git a/linux/linux.mk b/linux/linux.mk
index 5a0ba01..c7792d4 100644
--- a/linux/linux.mk
+++ b/linux/linux.mk
@@ -7,6 +7,9 @@
 LINUX_VERSION = $(call qstrip,$(BR2_LINUX_KERNEL_VERSION))
 LINUX_LICENSE = GPLv2
 LINUX_LICENSE_FILES = COPYING
+ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
+LINUX_INSTALL_STAGING=YES
+endif
 
 # Compute LINUX_SOURCE and LINUX_SITE from the configuration
 ifeq ($(BR2_LINUX_KERNEL_CUSTOM_TARBALL),y)
@@ -54,6 +57,7 @@ LINUX_MAKE_FLAGS = \
 	HOSTCFLAGS="$(HOSTCFLAGS)" \
 	ARCH=$(KERNEL_ARCH) \
 	INSTALL_MOD_PATH=$(TARGET_DIR) \
+	INSTALL_HDR_PATH="$(STAGING_DIR)/usr/src/linux-headers-$(LINUX_VERSION)" \
 	CROSS_COMPILE="$(CCACHE) $(TARGET_CROSS)" \
 	DEPMOD=$(HOST_DIR)/sbin/depmod
 
@@ -297,6 +301,11 @@ define LINUX_INSTALL_KERNEL_IMAGE_TO_TARGET
 endef
 endif
 
+ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
+define LINUX_INSTALL_STAGING_CMDS
+	$(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D) $(LINUX_TARGET_NAME) headers_install
+endef
+endif
 
 define LINUX_INSTALL_HOST_TOOLS
 	# Installing dtc (device tree compiler) as host tool, if selected
-- 
2.3.4

[Buildroot] [PATCH] linux: add an option to install kernel headers into staging

[Danomi Manchego]

Nicolas,

On Tue, Mar 24, 2015 at 6:00 AM, Nicolas Serafini
<nicolas.serafini@sensefly.com> wrote:
> The kernel headers are installed into /usr/src/linux-headers-version
> of the staging folder.
>
> These headers can be used, for example, by a post build script to
> install or update some new headers from the kernel in /usr/include of
> the staging.
>
> Signed-off-by: Nicolas Serafini <nicolas.serafini@sensefly.com>
> ---
>  linux/Config.in | 6 ++++++
>  linux/linux.mk  | 9 +++++++++
>  2 files changed, 15 insertions(+)
>
> diff --git a/linux/Config.in b/linux/Config.in
> index fa3232f..dd97211 100644
> --- a/linux/Config.in
> +++ b/linux/Config.in
> @@ -354,6 +354,12 @@ config BR2_LINUX_KERNEL_INSTALL_TARGET
>           /boot if DTBs have been generated by the kernel build
>           process.
>
> +config BR2_LINUX_KERNEL_INSTALL_HEADERS
> +       bool "Install kernel headers to staging"
> +       help
> +         Select this option to have the kernel headers installed to
> +         staging in /usr/src/linux-headers-version folder.
> +
>  # Linux extensions
>  source "linux/Config.ext.in"
>
> diff --git a/linux/linux.mk b/linux/linux.mk
> index 5a0ba01..c7792d4 100644
> --- a/linux/linux.mk
> +++ b/linux/linux.mk
> @@ -7,6 +7,9 @@
>  LINUX_VERSION = $(call qstrip,$(BR2_LINUX_KERNEL_VERSION))
>  LINUX_LICENSE = GPLv2
>  LINUX_LICENSE_FILES = COPYING
> +ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
> +LINUX_INSTALL_STAGING=YES
> +endif
>
>  # Compute LINUX_SOURCE and LINUX_SITE from the configuration
>  ifeq ($(BR2_LINUX_KERNEL_CUSTOM_TARBALL),y)
> @@ -54,6 +57,7 @@ LINUX_MAKE_FLAGS = \
>         HOSTCFLAGS="$(HOSTCFLAGS)" \
>         ARCH=$(KERNEL_ARCH) \
>         INSTALL_MOD_PATH=$(TARGET_DIR) \
> +       INSTALL_HDR_PATH="$(STAGING_DIR)/usr/src/linux-headers-$(LINUX_VERSION)" \
>         CROSS_COMPILE="$(CCACHE) $(TARGET_CROSS)" \
>         DEPMOD=$(HOST_DIR)/sbin/depmod
>
> @@ -297,6 +301,11 @@ define LINUX_INSTALL_KERNEL_IMAGE_TO_TARGET
>  endef
>  endif
>
> +ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
> +define LINUX_INSTALL_STAGING_CMDS
> +       $(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D) $(LINUX_TARGET_NAME) headers_install
> +endef
> +endif

Adding this is as a linux staging command means that it could install
the header files after other stuff gets built and installed, no?  I'm
wondering if this will imply needing (or recommending) to add
dependency on "linux" to other packages that might use kernel headers.
Things which write to the fb devices, for example.

No objection here, I'm just thinking about the use case.

Danomi -


>  define LINUX_INSTALL_HOST_TOOLS
>         # Installing dtc (device tree compiler) as host tool, if selected
> --
> 2.3.4
>
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

[Buildroot] [PATCH] linux: add an option to install kernel headers into staging

[Yann E. MORIN]

Nicolas, All,

On 2015-03-24 11:00 +0100, Nicolas Serafini spake thusly:
> The kernel headers are installed into /usr/src/linux-headers-version
> of the staging folder.
> 
> These headers can be used, for example, by a post build script to
> install or update some new headers from the kernel in /usr/include of
> the staging.

No, no. The kernel headers in staging are those that come from the
toolchain.

When the toolchain has been compiled, parts of it (notably the C
library) have been configured according to whatever API/ABI the kernel
headers where exporting to userland. Those headers can *not* be changed
after the fact.

So, this is a big NAK from me, sorry.

Regards,
Yann E. MORIN.

> Signed-off-by: Nicolas Serafini <nicolas.serafini@sensefly.com>
> ---
>  linux/Config.in | 6 ++++++
>  linux/linux.mk  | 9 +++++++++
>  2 files changed, 15 insertions(+)
> 
> diff --git a/linux/Config.in b/linux/Config.in
> index fa3232f..dd97211 100644
> --- a/linux/Config.in
> +++ b/linux/Config.in
> @@ -354,6 +354,12 @@ config BR2_LINUX_KERNEL_INSTALL_TARGET
>  	  /boot if DTBs have been generated by the kernel build
>  	  process.
>  
> +config BR2_LINUX_KERNEL_INSTALL_HEADERS
> +	bool "Install kernel headers to staging"
> +	help
> +	  Select this option to have the kernel headers installed to
> +	  staging in /usr/src/linux-headers-version folder.
> +
>  # Linux extensions
>  source "linux/Config.ext.in"
>  
> diff --git a/linux/linux.mk b/linux/linux.mk
> index 5a0ba01..c7792d4 100644
> --- a/linux/linux.mk
> +++ b/linux/linux.mk
> @@ -7,6 +7,9 @@
>  LINUX_VERSION = $(call qstrip,$(BR2_LINUX_KERNEL_VERSION))
>  LINUX_LICENSE = GPLv2
>  LINUX_LICENSE_FILES = COPYING
> +ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
> +LINUX_INSTALL_STAGING=YES
> +endif
>  
>  # Compute LINUX_SOURCE and LINUX_SITE from the configuration
>  ifeq ($(BR2_LINUX_KERNEL_CUSTOM_TARBALL),y)
> @@ -54,6 +57,7 @@ LINUX_MAKE_FLAGS = \
>  	HOSTCFLAGS="$(HOSTCFLAGS)" \
>  	ARCH=$(KERNEL_ARCH) \
>  	INSTALL_MOD_PATH=$(TARGET_DIR) \
> +	INSTALL_HDR_PATH="$(STAGING_DIR)/usr/src/linux-headers-$(LINUX_VERSION)" \
>  	CROSS_COMPILE="$(CCACHE) $(TARGET_CROSS)" \
>  	DEPMOD=$(HOST_DIR)/sbin/depmod
>  
> @@ -297,6 +301,11 @@ define LINUX_INSTALL_KERNEL_IMAGE_TO_TARGET
>  endef
>  endif
>  
> +ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
> +define LINUX_INSTALL_STAGING_CMDS
> +	$(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D) $(LINUX_TARGET_NAME) headers_install
> +endef
> +endif
>  
>  define LINUX_INSTALL_HOST_TOOLS
>  	# Installing dtc (device tree compiler) as host tool, if selected
> -- 
> 2.3.4
> 
> _______________________________________________
> buildroot mailing list
> buildroot at busybox.net
> http://lists.busybox.net/mailman/listinfo/buildroot

-- 
.-----------------.--------------------.------------------.--------------------.
|  Yann E. MORIN  | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: |
| +33 662 376 056 | Software  Designer | \ / CAMPAIGN     |  ___               |
| +33 223 225 172 `------------.-------:  X  AGAINST      |  \e/  There is no  |
| http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL    |   v   conspiracy.  |
'------------------------------^-------^------------------^--------------------'

[Buildroot] [PATCH] linux: add an option to install kernel headers into staging

[Thomas Petazzoni]

Dear Nicolas Serafini,

On Tue, 24 Mar 2015 11:00:30 +0100, Nicolas Serafini wrote:
> The kernel headers are installed into /usr/src/linux-headers-version
> of the staging folder.
> 
> These headers can be used, for example, by a post build script to
> install or update some new headers from the kernel in /usr/include of
> the staging.

Can you give some more details and background about the issue you're
trying to solve? You're only explaining what your solution is, but not
what the original problem is.

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

[Buildroot] [PATCH] linux: add an option to install kernel headers into staging

[Nicolas Serafini]

Danomi, All,

On Tue, 24 Mar 2015 15:45:40 -0400
Danomi Manchego <danomimanchego123@gmail.com> wrote:

> Nicolas,
> 
> On Tue, Mar 24, 2015 at 6:00 AM, Nicolas Serafini
> <nicolas.serafini@sensefly.com> wrote:
> > The kernel headers are installed into /usr/src/linux-headers-version
> > of the staging folder.
> >
> > These headers can be used, for example, by a post build script to
> > install or update some new headers from the kernel in /usr/include
> > of the staging.
> >
> > Signed-off-by: Nicolas Serafini <nicolas.serafini@sensefly.com>
> > ---
> >  linux/Config.in | 6 ++++++
> >  linux/linux.mk  | 9 +++++++++
> >  2 files changed, 15 insertions(+)
> >
> > diff --git a/linux/Config.in b/linux/Config.in
> > index fa3232f..dd97211 100644
> > --- a/linux/Config.in
> > +++ b/linux/Config.in
> > @@ -354,6 +354,12 @@ config BR2_LINUX_KERNEL_INSTALL_TARGET
> >           /boot if DTBs have been generated by the kernel build
> >           process.
> >
> > +config BR2_LINUX_KERNEL_INSTALL_HEADERS
> > +       bool "Install kernel headers to staging"
> > +       help
> > +         Select this option to have the kernel headers installed to
> > +         staging in /usr/src/linux-headers-version folder.
> > +
> >  # Linux extensions
> >  source "linux/Config.ext.in"
> >
> > diff --git a/linux/linux.mk b/linux/linux.mk
> > index 5a0ba01..c7792d4 100644
> > --- a/linux/linux.mk
> > +++ b/linux/linux.mk
> > @@ -7,6 +7,9 @@
> >  LINUX_VERSION = $(call qstrip,$(BR2_LINUX_KERNEL_VERSION))
> >  LINUX_LICENSE = GPLv2
> >  LINUX_LICENSE_FILES = COPYING
> > +ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
> > +LINUX_INSTALL_STAGING=YES
> > +endif
> >
> >  # Compute LINUX_SOURCE and LINUX_SITE from the configuration
> >  ifeq ($(BR2_LINUX_KERNEL_CUSTOM_TARBALL),y)
> > @@ -54,6 +57,7 @@ LINUX_MAKE_FLAGS = \
> >         HOSTCFLAGS="$(HOSTCFLAGS)" \
> >         ARCH=$(KERNEL_ARCH) \
> >         INSTALL_MOD_PATH=$(TARGET_DIR) \
> > +
> > INSTALL_HDR_PATH="$(STAGING_DIR)/usr/src/linux-headers-$(LINUX_VERSION)"
> > \ CROSS_COMPILE="$(CCACHE) $(TARGET_CROSS)" \
> > DEPMOD=$(HOST_DIR)/sbin/depmod
> >
> > @@ -297,6 +301,11 @@ define LINUX_INSTALL_KERNEL_IMAGE_TO_TARGET
> >  endef
> >  endif
> >
> > +ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
> > +define LINUX_INSTALL_STAGING_CMDS
> > +       $(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D)
> > $(LINUX_TARGET_NAME) headers_install +endef
> > +endif
> 
> Adding this is as a linux staging command means that it could install
> the header files after other stuff gets built and installed, no?  I'm
> wondering if this will imply needing (or recommending) to add
> dependency on "linux" to other packages that might use kernel headers.
> Things which write to the fb devices, for example.

You do not need dependency on these staging headers because kernel
headers are already installed by the toolchain and are parts of the C
library.

Regards,
Nicolas

> 
> No objection here, I'm just thinking about the use case.
> 
> Danomi -
> 
> 
> >  define LINUX_INSTALL_HOST_TOOLS
> >         # Installing dtc (device tree compiler) as host tool, if
> > selected --
> > 2.3.4
> >
> > _______________________________________________
> > buildroot mailing list
> > buildroot at busybox.net
> > http://lists.busybox.net/mailman/listinfo/buildroot



-- 
Nicolas Serafini
R&D Embedded Software Engineer

www.sensefly.com
Route de Gen?ve 38
1033 Cheseaux-Lausanne
Switzerland

[Buildroot] [PATCH] linux: add an option to install kernel headers into staging

[Nicolas Serafini]

Thomas, all,

On Wed, 25 Mar 2015 00:57:55 +0100
Thomas Petazzoni <thomas.petazzoni@free-electrons.com> wrote:

> Dear Nicolas Serafini,
> 
> On Tue, 24 Mar 2015 11:00:30 +0100, Nicolas Serafini wrote:
> > The kernel headers are installed into /usr/src/linux-headers-version
> > of the staging folder.
> > 
> > These headers can be used, for example, by a post build script to
> > install or update some new headers from the kernel in /usr/include
> > of the staging.
> 
> Can you give some more details and background about the issue you're
> trying to solve? You're only explaining what your solution is, but not
> what the original problem is.

I have explain my problem in the mail response to Yann.

Regards,
Nicolas

> 
> Best regards,
> 
> Thomas



-- 
Nicolas Serafini
R&D Embedded Software Engineer

www.sensefly.com
Route de Gen?ve 38
1033 Cheseaux-Lausanne
Switzerland

[Buildroot] [PATCH] linux: add an option to install kernel headers into staging

[Nicolas Serafini]

Yann, All,

On Tue, 24 Mar 2015 21:57:09 +0100
"Yann E. MORIN" <yann.morin.1998@free.fr> wrote:

> Nicolas, All,
> 
> On 2015-03-24 11:00 +0100, Nicolas Serafini spake thusly:
> > The kernel headers are installed into /usr/src/linux-headers-version
> > of the staging folder.
> > 
> > These headers can be used, for example, by a post build script to
> > install or update some new headers from the kernel in /usr/include
> > of the staging.
> 
> No, no. The kernel headers in staging are those that come from the
> toolchain.

Yes I'm ok with that.

> 
> When the toolchain has been compiled, parts of it (notably the C
> library) have been configured according to whatever API/ABI the kernel
> headers where exporting to userland. Those headers can *not* be
> changed after the fact.
> 
> So, this is a big NAK from me, sorry.

It's possible my example is not good. I'm ok with the fact that
headers can not be changed after but if you have a custom kernel with
new custom API and you want to build userspace software that use theses
API you need to have new headers into staging.

I'm going to explain my case. For me Buildroot is a part of a biggest
build system. Buildroot is used to build/generate the bootloader, the
kernel and the rootfs. After that, the global build system use the
output of buildroot to build our own software.

I have a custom kernel with new API that are used by some userspace
software and this patch give only a way to retrieve these cleaned
headers (#ifdef KERNEL removed) correctly exported by the kernel
instead of taking headers directly into the kernel source.
It's why theses headers are into /usr/src/linux-headers-version instead
of /usr/include

Regards,

Nicolas



> 
> Regards,
> Yann E. MORIN.
> 
> > Signed-off-by: Nicolas Serafini <nicolas.serafini@sensefly.com>
> > ---
> >  linux/Config.in | 6 ++++++
> >  linux/linux.mk  | 9 +++++++++
> >  2 files changed, 15 insertions(+)
> > 
> > diff --git a/linux/Config.in b/linux/Config.in
> > index fa3232f..dd97211 100644
> > --- a/linux/Config.in
> > +++ b/linux/Config.in
> > @@ -354,6 +354,12 @@ config BR2_LINUX_KERNEL_INSTALL_TARGET
> >  	  /boot if DTBs have been generated by the kernel build
> >  	  process.
> >  
> > +config BR2_LINUX_KERNEL_INSTALL_HEADERS
> > +	bool "Install kernel headers to staging"
> > +	help
> > +	  Select this option to have the kernel headers installed
> > to
> > +	  staging in /usr/src/linux-headers-version folder.
> > +
> >  # Linux extensions
> >  source "linux/Config.ext.in"
> >  
> > diff --git a/linux/linux.mk b/linux/linux.mk
> > index 5a0ba01..c7792d4 100644
> > --- a/linux/linux.mk
> > +++ b/linux/linux.mk
> > @@ -7,6 +7,9 @@
> >  LINUX_VERSION = $(call qstrip,$(BR2_LINUX_KERNEL_VERSION))
> >  LINUX_LICENSE = GPLv2
> >  LINUX_LICENSE_FILES = COPYING
> > +ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
> > +LINUX_INSTALL_STAGING=YES
> > +endif
> >  
> >  # Compute LINUX_SOURCE and LINUX_SITE from the configuration
> >  ifeq ($(BR2_LINUX_KERNEL_CUSTOM_TARBALL),y)
> > @@ -54,6 +57,7 @@ LINUX_MAKE_FLAGS = \
> >  	HOSTCFLAGS="$(HOSTCFLAGS)" \
> >  	ARCH=$(KERNEL_ARCH) \
> >  	INSTALL_MOD_PATH=$(TARGET_DIR) \
> > +
> > INSTALL_HDR_PATH="$(STAGING_DIR)/usr/src/linux-headers-$(LINUX_VERSION)"
> > \ CROSS_COMPILE="$(CCACHE) $(TARGET_CROSS)" \
> > DEPMOD=$(HOST_DIR)/sbin/depmod 
> > @@ -297,6 +301,11 @@ define LINUX_INSTALL_KERNEL_IMAGE_TO_TARGET
> >  endef
> >  endif
> >  
> > +ifeq ($(BR2_LINUX_KERNEL_INSTALL_HEADERS),y)
> > +define LINUX_INSTALL_STAGING_CMDS
> > +	$(LINUX_MAKE_ENV) $(MAKE) $(LINUX_MAKE_FLAGS) -C $(@D)
> > $(LINUX_TARGET_NAME) headers_install +endef
> > +endif
> >  
> >  define LINUX_INSTALL_HOST_TOOLS
> >  	# Installing dtc (device tree compiler) as host tool, if
> > selected -- 
> > 2.3.4
> > 
> > _______________________________________________
> > buildroot mailing list
> > buildroot at busybox.net
> > http://lists.busybox.net/mailman/listinfo/buildroot
> 



-- 
Nicolas Serafini
R&D Embedded Software Engineer

www.sensefly.com
Route de Gen?ve 38
1033 Cheseaux-Lausanne
Switzerland