NetCube-Systems-Austria/kumquat-buildroot
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

package/linux-headers: add option to use same sources as the kernel

Browse Source 
Some heavily (and most often improperly) modified Linux kernels may export
new APIs to userland, so as to speak to custom hardware or custom kernel
facilities.

However, we currently have no easy way to use such kernels as a source
for the linux-headers package, which precludes having those userland
headers intalled for userland applications to use them.

We do have a way for the kernel to use the same version as for the
headers, but that is definitely not enough, as the linux-headers package
has a version choice that is far less versatile and capable than that of
the linux package.

Add a new option for the linux-headers package, for the user to specify
that the version (really, the sources) of the kernel be used to install
the headers from.

We do that by making linux-headers patch-depend on the linux package.

We can't have linux-header simply depend on linux, because the simple
dependency means the the dependee will be configured, built and installed
before the dependent is configured. And since linux is a target package,
it depends on the toolchain, which internally dependes on linux-headers,
which would depend on linux, and we'd get a circular dependency.

Using patch-depend will ensure that linux is extracted and patched
before linux-headers is extracted, which is really all we need.

Then, we install the headers from the linux source tree, rather than
from linux-headers' source tree (as there's nothing in there!).

Since we need to install a private set for uClibc (see cde947f, uclibc:
prevent rebuilding after installation to staging), we explicitly set
INSTALL_HDR_PATH when calling the kernel' install-headers rule in
LINUX_HEADERS_CONFIGURE_CMDS, so that the headers are installed in
linux-headers' $(@D) instead of linux' $(@D).

Finally, as there is no way to know the kernel version in this case, we
must still prompt the user for the kernel series the headers are from
(like we do for a custom version) and check for consistency at build
time.

Note however that this still leaves users that want to built their
such-kernel outside of Buildroot out in the cold.

[Peter: drop comment as suggested by Thomas]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Karoly Kasza <kaszak@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Peter Korsgaard <jacmet@uclibc.org>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
This commit is contained in:
Yann E. MORIN 2016-01-20 19:34:28 +01:00 committed by Peter Korsgaard
parent c823c6ee6a
commit 63abfb7210
3 changed files with 29 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
linux/Config.in
View File

@ -31,6 +31,7 @@ config BR2_LINUX_KERNEL_LATEST_VERSION
config BR2_LINUX_KERNEL_SAME_AS_HEADERS
bool "Same as toolchain kernel headers"
depends on !BR2_KERNEL_HEADERS_AS_KERNEL
depends on BR2_TOOLCHAIN_BUILDROOT
help
This option will re-use the same kernel sources as the one

7
package/linux-headers/Config.in.host
View File

@ -5,12 +5,17 @@ comment "Kernel Header Options"
choice
prompt "Kernel Headers"
default BR2_KERNEL_HEADERS_AS_KERNEL if BR2_LINUX_KERNEL
default BR2_KERNEL_HEADERS_4_4
help
Select the version of kernel header files you wish to use.
You must select the correct set of header files to match
the kernel you intend to use on your target system.
config BR2_KERNEL_HEADERS_AS_KERNEL
bool "Same as kernel"
depends on BR2_LINUX_KERNEL
config BR2_KERNEL_HEADERS_3_2
bool "Linux 3.2.x kernel headers"
depends on !BR2_arc && !BR2_nios2
@ -87,7 +92,7 @@ config BR2_DEFAULT_KERNEL_VERSION
choice
bool "Custom kernel headers series"
depends on BR2_KERNEL_HEADERS_VERSION
depends on BR2_KERNEL_HEADERS_VERSION || BR2_KERNEL_HEADERS_AS_KERNEL
default BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_REALLY_OLD
help
Set to the kernel headers series you manually set above.

25
package/linux-headers/linux-headers.mk
View File

@ -7,6 +7,19 @@
# This package is used to provide Linux kernel headers for the
# internal toolchain backend.
ifeq ($(BR2_KERNEL_HEADERS_AS_KERNEL),y)
LINUX_HEADERS_VERSION = none
LINUX_HEADERS_SOURCE =
LINUX_HEADERS_LICENSE = $(LINUX_LICENSE)
LINUX_HEADERS_LICENSE_FILES = $(LINUX_LICENSE_FILES)
LINUX_HEADERS_PATCH_DEPENDENCIES = linux
LINUX_HEADERS_REAL_DIR = $(LINUX_DIR)
else # ! BR2_KERNEL_HEADERS_AS_KERNEL
LINUX_HEADERS_VERSION = $(call qstrip,$(BR2_DEFAULT_KERNEL_HEADERS))
ifeq ($(findstring x2.6.,x$(LINUX_HEADERS_VERSION)),x2.6.)
LINUX_HEADERS_SITE = $(BR2_KERNEL_MIRROR)/linux/kernel/v2.6
@ -16,9 +29,14 @@ else ifeq ($(findstring x4.,x$(LINUX_HEADERS_VERSION)),x4.)
LINUX_HEADERS_SITE = $(BR2_KERNEL_MIRROR)/linux/kernel/v4.x
endif
LINUX_HEADERS_SOURCE = linux-$(LINUX_HEADERS_VERSION).tar.xz
LINUX_HEADERS_LICENSE = GPLv2
LINUX_HEADERS_LICENSE_FILES = COPYING
LINUX_HEADERS_REAL_DIR = $(@D)
endif # ! BR2_KERNEL_HEADERS_AS_KERNEL
LINUX_HEADERS_INSTALL_STAGING = YES
# linux-headers is part of the toolchain so disable the toolchain dependency
@ -35,17 +53,18 @@ LINUX_HEADERS_ADD_TOOLCHAIN_DEPENDENCY = NO
# uClibc building. This way uClibc doesn't modify linux headers on installation
# of "its" headers
define LINUX_HEADERS_CONFIGURE_CMDS
(cd $(@D); \
(cd $(LINUX_HEADERS_REAL_DIR); \
$(TARGET_MAKE_ENV) $(MAKE) \
ARCH=$(KERNEL_ARCH) \
HOSTCC="$(HOSTCC)" \
HOSTCFLAGS="$(HOSTCFLAGS)" \
HOSTCXX="$(HOSTCXX)" \
INSTALL_HDR_PATH=$(@D)/usr \
headers_install)
endef
define LINUX_HEADERS_INSTALL_STAGING_CMDS
(cd $(@D); \
(cd $(LINUX_HEADERS_REAL_DIR); \
$(TARGET_MAKE_ENV) $(MAKE) \
ARCH=$(KERNEL_ARCH) \
HOSTCC="$(HOSTCC)" \
@ -55,7 +74,7 @@ define LINUX_HEADERS_INSTALL_STAGING_CMDS
headers_install)
endef
ifeq ($(BR2_KERNEL_HEADERS_VERSION),y)
ifeq ($(BR2_KERNEL_HEADERS_VERSION)$(BR2_KERNEL_HEADERS_AS_KERNEL),y)
define LINUX_HEADERS_CHECK_VERSION
$(call check_kernel_headers_version,\
$(STAGING_DIR),\