Re: [PATCH v6] kernel: Add support for multiple kernel packages

[Haris Okanovic <haris.okanovic@ni.com>]

On 08/16/2017 11:00 AM, Wold, Saul wrote:
> On Mon, 2017-08-14 at 16:29 -0500, Haris Okanovic wrote:
>> Some distros may want to provide alternate kernel "flavors" via feeds
>> or
>> within bootable images. For example, readily available builds which
>> provide certain diagnostic features can enable developers and testers
>> to
>> more quickly resolve issues by avoiding lengthy kernel builds.
>>
>> This change allows for building multiple flavors of the kernel and
>> module packages by templatizing kernel package names via a new
>> KERNEL_PACKAGE_NAME variable in kernel.bbclass. It defaults to the
>> old
>> name of "kernel", but can be overridden by certain recipes providing
>> alternate kernel flavors.
>>
>> To maintain compatibility, recipes providing alternate kernel flavors
>> cannot be the "preferred provider" for virtual/kernel. This is
>> because
>> OE puts the preferred provider's build and source at
>> "tmp-glibc/work-shared/$MACHINE/kernel-build-artifacts/" and
>> "tmp-glibc/work-shared/$MACHINE/kernel-source/" instead of
>> "tmp-glibc/work/*/$PN/" like other recipes. Therefore, recipes using
>> the
>> default KERNEL_PACKAGE_NAME="kernel" follows the old semantics --
>> build
>> in the old location and may be preferred provider -- while recipes
>> using
>> all other KERNEL_PACKAGE_NAME's build from the normal WORKDIR and
>> don't
>> provide "virtual/kernel".
>>
>> Testing:
>>   1. Prepended `KERNEL_PACKAGE_NAME = "tiny-linux"` to
>>      linux-yocto-tiny_4.9.bb so that it may build alongside
>>      the main kernel.
>>   2. `bitbake linux-yocto linux-yocto-tiny` to build both kernel
>> flavors.
>>   3. Verified image and modules IPKs exist for both:
>>      tmp-glibc/deploy/ipk/qemux86/kernel-* for linux-yocto
>>      tmp-glibc/deploy/ipk/qemux86/tiny-linux* for linux-yocto-tiny
>>   4. Verified linux-yocto is the "preferred provider", and was built
>> in
>>      shared directory: tmp-glibc/work-shared/qemux86/kernel-*
>>   5. Appended `CORE_IMAGE_BASE_INSTALL += "tiny-linux"` to
>>      core-image-base.bb to include both kernel flavors.
>>   6. `bitbake core-image-base` to build an image.
>>   7. Verified image contains two bzImage's under /boot/, with
>>      "yocto-standard" selected to boot via symlink.
>>
>> Discussion threads:
>> https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.openembedded.org_pipermail_openembedded-2Dcore_2015-2DDecemb&d=DwIGaQ&c=I_0YwoKy7z5LMTVdyO6YCiE2uzI1jjZZuIPelcSjixA&r=8Bziuw3IaCGjyrSAphuGwHmVdHcVwza-srUYwL9U_Ms&m=0QcXD-YEVpGbAgVAWiuCmMnvCng6N5j5KrqqwqXHW2E&s=88YT5OEfyAkDMCqrZzRoGH6Z8DsSjP8nfCmrq4fronk&e=
>> er/thread.html#114122
>> https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.openembedded.org_pipermail_openembedded-2Dcore_2017-2DJuly_t&d=DwIGaQ&c=I_0YwoKy7z5LMTVdyO6YCiE2uzI1jjZZuIPelcSjixA&r=8Bziuw3IaCGjyrSAphuGwHmVdHcVwza-srUYwL9U_Ms&m=0QcXD-YEVpGbAgVAWiuCmMnvCng6N5j5KrqqwqXHW2E&s=2NjYYuy80NctfYU9vcnLPueVm9rALs-0nFjVd5cnY8w&e=
>> hread.html#139130
>>
>> Signed-off-by: Ioan-Adrian Ratiu <adrian.ratiu@ni.com>
>> Signed-off-by: Gratian Crisan <gratian.crisan@ni.com>
>> Signed-off-by: Haris Okanovic <haris.okanovic@ni.com>
>> Coauthored-by: Gratian Crisan <gratian.crisan@ni.com>
>> Coauthored-by: Haris Okanovic <haris.okanovic@ni.com>
>> Coauthored-by: Josh Hernstrom <josh.hernstrom@ni.com>
>> ---
>> [PATCH v2] Change STAGING_KERNEL_DIR and STAGING_KERNEL_BUILDDIR to
>> the
>> "work" directory in alternate kernel builds, instead of "work-
>> shared",
>> so
>> that the two builds don't clobber each other.
>>
>> [PATCH v3] An updated version of this change rebased onto the current
>> OE-core master. Changes:
>>   - Remove PREFERRED_PROVIDER check in linux-yocto.inc in alternate
>>     kernel builds, since alternate kernels aren't the
>>     PREFERRED_PROVIDER for virtual/kernel by definition.
>>   - Remove "virtual/kernel" from PROVIDES in alternate kernel builds.
>>
>> [PATCH v4] Another rebase onto master; no functional change.
>> Improved description and testing steps.
>>
>> [PATCH v5]
>>   - Warn when PN == KERNEL_PACKAGE_NAME (bug # 11905)
>>   - Add KERNEL_DEPLOYSUBDIR to avoid DEPLOYDIR collisions
>>
>> [PATCH v6] Add KERNEL_PACKAGE_NAME to kernel-module-split.bbclass for
>> module recipes; fixes lttng-modules build.
>>
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_harisokanovic_openembedded-2Dcore_tree_dev_hokanovi_&d=DwIGaQ&c=I_0YwoKy7z5LMTVdyO6YCiE2uzI1jjZZuIPelcSjixA&r=8Bziuw3IaCGjyrSAphuGwHmVdHcVwza-srUYwL9U_Ms&m=0QcXD-YEVpGbAgVAWiuCmMnvCng6N5j5KrqqwqXHW2E&s=HlNgsQzUBE7Qo-WEzXqkx8xf814iqTLQbr-EqAENFKs&e=
>> multi-kernel-packages-v6
>> ---
>>   meta/classes/kernel-module-split.bbclass  |  14 +++-
>>   meta/classes/kernel.bbclass               | 114 +++++++++++++++++++-
>> ----------
>>   meta/conf/documentation.conf              |   1 +
>>   meta/recipes-kernel/linux/linux-dtb.inc   |   2 +-
>>   meta/recipes-kernel/linux/linux-yocto.inc |   2 +-
>>   5 files changed, 86 insertions(+), 47 deletions(-)
>>
>> diff --git a/meta/classes/kernel-module-split.bbclass
>> b/meta/classes/kernel-module-split.bbclass
>> index 1035525dac..59f19f3de2 100644
>> --- a/meta/classes/kernel-module-split.bbclass
>> +++ b/meta/classes/kernel-module-split.bbclass
>> @@ -30,7 +30,12 @@ do_install_append() {
>>   
>>   PACKAGESPLITFUNCS_prepend = "split_kernel_module_packages "
>>   
>> -KERNEL_MODULES_META_PACKAGE ?= "kernel-modules"
>> +# Default KERNEL_PACKAGE_NAME should match kernel.bbclass
>> +# Redefined here since some recipes only build modules and therefore
>> +# don't consume kernel.bbclass to get this default.
>> +KERNEL_PACKAGE_NAME ??= "kernel"
>> +
>> +KERNEL_MODULES_META_PACKAGE ?= "${KERNEL_PACKAGE_NAME}-modules"
>>   
> Sorry, I missed that you sent this on Monday when I replied to your
> "thoughts?" question from V5.
> 
> I think we should really be checking if KERNEL_PACKAGE_NAME is set
> already when you use it and default to kernel if it does not exist
> rather than having 2 places where KERNEL_PACKAGE_NAME is ??= set.
> 
> Sorry about the timing.
> 

Np. I removed a second definition from kernel-module-split.bbclass and 
applied the default of "kernel" in the two places it's used. Clean 
rebuild of lttng-modules, linux-yocto-tiny, and linux-yocto still works!

I'll post a v7 shortly.

-- Haris

> Sau!
> 
>>   KERNEL_MODULE_PACKAGE_PREFIX ?= ""
>>   KERNEL_MODULE_PACKAGE_SUFFIX ?= "-${KERNEL_VERSION}"
>> @@ -129,16 +134,19 @@ python split_kernel_module_packages () {
>>              postfix = format.split('%s')[1]
>>              d.setVar('RPROVIDES_' + pkg, pkg.replace(postfix, ''))
>>   
>> +    kernel_package_name = d.getVar("KERNEL_PACKAGE_NAME", True)
>> +    kernel_version = d.getVar("KERNEL_VERSION", True)
>> +
>>       module_regex = '^(.*)\.k?o$'
>>   
>>       module_pattern_prefix = d.getVar('KERNEL_MODULE_PACKAGE_PREFIX')
>>       module_pattern_suffix = d.getVar('KERNEL_MODULE_PACKAGE_SUFFIX')
>> -    module_pattern = module_pattern_prefix + 'kernel-module-%s' +
>> module_pattern_suffix
>> +    module_pattern = module_pattern_prefix + kernel_package_name +
>> '-module-%s' + module_pattern_suffix
>>   
>>       postinst = d.getVar('pkg_postinst_modules')
>>       postrm = d.getVar('pkg_postrm_modules')
>>   
>> -    modules = do_split_packages(d,
>> root='${nonarch_base_libdir}/modules', file_regex=module_regex,
>> output_pattern=module_pattern, description='%s kernel module',
>> postinst=postinst, postrm=postrm, recursive=True, hook=frob_metadata,
>> extra_depends='kernel-%s' % (d.getVar("KERNEL_VERSION")))
>> +    modules = do_split_packages(d,
>> root='${nonarch_base_libdir}/modules', file_regex=module_regex,
>> output_pattern=module_pattern, description='%s kernel module',
>> postinst=postinst, postrm=postrm, recursive=True, hook=frob_metadata,
>> extra_depends='%s-%s' % (kernel_package_name, kernel_version))
>>       if modules:
>>           metapkg = d.getVar('KERNEL_MODULES_META_PACKAGE')
>>           d.appendVar('RDEPENDS_' + metapkg, ' '+' '.join(modules))
>> diff --git a/meta/classes/kernel.bbclass
>> b/meta/classes/kernel.bbclass
>> index 7670c7107a..0760bfb2c9 100644
>> --- a/meta/classes/kernel.bbclass
>> +++ b/meta/classes/kernel.bbclass
>> @@ -1,6 +1,9 @@
>>   inherit linux-kernel-base kernel-module-split
>>   
>> -PROVIDES += "virtual/kernel"
>> +KERNEL_PACKAGE_NAME ??= "kernel"
>> +KERNEL_DEPLOYSUBDIR ??= "${@ "" if (d.getVar("KERNEL_PACKAGE_NAME",
>> True) == "kernel") else d.getVar("KERNEL_PACKAGE_NAME", True) }"
>> +
>> +PROVIDES += "${@ "virtual/kernel" if
>> (d.getVar("KERNEL_PACKAGE_NAME", True) == "kernel") else "" }"
>>   DEPENDS += "virtual/${TARGET_PREFIX}binutils
>> virtual/${TARGET_PREFIX}gcc kmod-native bc-native lzop-native"
>>   PACKAGE_WRITE_DEPS += "depmodwrapper-cross virtual/update-
>> alternatives-native"
>>   
>> @@ -32,11 +35,32 @@ KERNEL_VERSION_PKG_NAME = "${@legitimize_package_
>> name(d.getVar('KERNEL_VERSION')
>>   KERNEL_VERSION_PKG_NAME[vardepvalue] = "${LINUX_VERSION}"
>>   
>>   python __anonymous () {
>> +    pn = d.getVar("PN", True)
>> +    kpn = d.getVar("KERNEL_PACKAGE_NAME", True)
>> +
>> +    # XXX Remove this after bug 11905 is resolved
>> +    #  FILES_${KERNEL_PACKAGE_NAME}-dev doesn't expand correctly
>> +    if kpn == pn:
>> +        bb.warn("Some packages (E.g. *-dev) might be missing due to
>> "
>> +                "bug 11905 (variable KERNEL_PACKAGE_NAME == PN)")
>> +
>> +    # The default kernel recipe builds in a shared location defined
>> by
>> +    # bitbake/distro confs: STAGING_KERNEL_DIR and
>> STAGING_KERNEL_BUILDDIR.
>> +    # Set these variables to directories under ${WORKDIR} in
>> alternate
>> +    # kernel recipes (I.e. where KERNEL_PACKAGE_NAME != kernel) so
>> that they
>> +    # may build in parallel with the default kernel without
>> clobbering.
>> +    if kpn != "kernel":
>> +        workdir = d.getVar("WORKDIR", True)
>> +        sourceDir = os.path.join(workdir, 'kernel-source')
>> +        artifactsDir = os.path.join(workdir, 'kernel-build-
>> artifacts')
>> +        d.setVar("STAGING_KERNEL_DIR", sourceDir)
>> +        d.setVar("STAGING_KERNEL_BUILDDIR", artifactsDir)
>>   
>>       # Merge KERNEL_IMAGETYPE and KERNEL_ALT_IMAGETYPE into
>> KERNEL_IMAGETYPES
>>       type = d.getVar('KERNEL_IMAGETYPE') or ""
>>       alttype = d.getVar('KERNEL_ALT_IMAGETYPE') or ""
>>       types = d.getVar('KERNEL_IMAGETYPES') or ""
>> +    kname = d.getVar('KERNEL_PACKAGE_NAME', True) or "kernel"
>>       if type not in types.split():
>>           types = (type + ' ' + types).strip()
>>       if alttype not in types.split():
>> @@ -53,22 +77,22 @@ python __anonymous () {
>>           typelower = type.lower()
>>           imagedest = d.getVar('KERNEL_IMAGEDEST')
>>   
>> -        d.appendVar('PACKAGES', ' ' + 'kernel-image-' + typelower)
>> +        d.appendVar('PACKAGES', ' %s-image-%s' % (kname, typelower))
>>   
>> -        d.setVar('FILES_kernel-image-' + typelower, '/' + imagedest
>> + '/' + type + '-${KERNEL_VERSION_NAME}')
>> +        d.setVar('FILES_' + kname + '-image-' + typelower, '/' +
>> imagedest + '/' + type + '-${KERNEL_VERSION_NAME}')
>>   
>> -        d.appendVar('RDEPENDS_kernel-image', ' ' + 'kernel-image-' +
>> typelower)
>> +        d.appendVar('RDEPENDS_%s-image' % kname, ' %s-image-%s' %
>> (kname, typelower))
>>   
>> -        d.setVar('PKG_kernel-image-' + typelower, 'kernel-image-' +
>> typelower + '-${KERNEL_VERSION_PKG_NAME}')
>> +        d.setVar('PKG_%s-image-%s' % (kname,typelower), '%s-image-
>> %s-${KERNEL_VERSION_PKG_NAME}' % (kname, typelower))
>>   
>> -        d.setVar('ALLOW_EMPTY_kernel-image-' + typelower, '1')
>> +        d.setVar('ALLOW_EMPTY_%s-image-%s' % (kname, typelower),
>> '1')
>>   
>>           priority = d.getVar('KERNEL_PRIORITY')
>>           postinst = '#!/bin/sh\n' + 'update-alternatives --install /'
>> + imagedest + '/' + type + ' ' + type + ' ' + type + '-
>> ${KERNEL_VERSION_NAME} ' + priority + ' || true' + '\n'
>> -        d.setVar('pkg_postinst_kernel-image-' + typelower, postinst)
>> +        d.setVar('pkg_postinst_' + kname + '-image-' + typelower,
>> postinst)
>>   
>>           postrm = '#!/bin/sh\n' + 'update-alternatives --remove' + '
>> ' + type + ' ' + type + '-${KERNEL_VERSION_NAME} || true' + '\n'
>> -        d.setVar('pkg_postrm_kernel-image-' + typelower, postrm)
>> +        d.setVar('pkg_postrm_%s-image-%s' % (kname, typelower),
>> postrm)
>>   
>>       image = d.getVar('INITRAMFS_IMAGE')
>>       if image:
>> @@ -126,9 +150,9 @@ base_do_unpack_append () {
>>   
>>   inherit kernel-arch deploy
>>   
>> -PACKAGES_DYNAMIC += "^kernel-module-.*"
>> -PACKAGES_DYNAMIC += "^kernel-image-.*"
>> -PACKAGES_DYNAMIC += "^kernel-firmware-.*"
>> +PACKAGES_DYNAMIC += "^${KERNEL_PACKAGE_NAME}-module-.*"
>> +PACKAGES_DYNAMIC += "^${KERNEL_PACKAGE_NAME}-image-.*"
>> +PACKAGES_DYNAMIC += "^${KERNEL_PACKAGE_NAME}-firmware-.*"
>>   
>>   export OS = "${TARGET_OS}"
>>   export CROSS_COMPILE = "${TARGET_PREFIX}"
>> @@ -371,9 +395,9 @@ do_shared_workdir_setscene () {
>>   
>>   emit_depmod_pkgdata() {
>>   	# Stash data for depmod
>> -	install -d ${PKGDESTWORK}/kernel-depmod/
>> -	echo "${KERNEL_VERSION}" > ${PKGDESTWORK}/kernel-
>> depmod/kernel-abiversion
>> -	cp ${B}/System.map ${PKGDESTWORK}/kernel-depmod/System.map-
>> ${KERNEL_VERSION}
>> +	install -d ${PKGDESTWORK}/${KERNEL_PACKAGE_NAME}-depmod/
>> +	echo "${KERNEL_VERSION}" >
>> ${PKGDESTWORK}/${KERNEL_PACKAGE_NAME}-depmod/${KERNEL_PACKAGE_NAME}-
>> abiversion
>> +	cp ${B}/System.map ${PKGDESTWORK}/${KERNEL_PACKAGE_NAME}-
>> depmod/System.map-${KERNEL_VERSION}
>>   }
>>   
>>   PACKAGEFUNCS += "emit_depmod_pkgdata"
>> @@ -388,7 +412,7 @@ do_shared_workdir () {
>>   	# Store the kernel version in sysroots for module-
>> base.bbclass
>>   	#
>>   
>> -	echo "${KERNEL_VERSION}" > $kerneldir/kernel-abiversion
>> +	echo "${KERNEL_VERSION}" >
>> $kerneldir/${KERNEL_PACKAGE_NAME}-abiversion
>>   
>>   	# Copy files required for module builds
>>   	cp System.map $kerneldir/System.map-${KERNEL_VERSION}
>> @@ -486,28 +510,28 @@ EXPORT_FUNCTIONS do_compile do_install
>> do_configure
>>   
>>   # kernel-base becomes kernel-${KERNEL_VERSION}
>>   # kernel-image becomes kernel-image-${KERNEL_VERSION}
>> -PACKAGES = "kernel kernel-base kernel-vmlinux kernel-image kernel-
>> dev kernel-modules"
>> +PACKAGES = "${KERNEL_PACKAGE_NAME} ${KERNEL_PACKAGE_NAME}-base
>> ${KERNEL_PACKAGE_NAME}-vmlinux ${KERNEL_PACKAGE_NAME}-image
>> ${KERNEL_PACKAGE_NAME}-dev ${KERNEL_PACKAGE_NAME}-modules"
>>   FILES_${PN} = ""
>> -FILES_kernel-base =
>> "${nonarch_base_libdir}/modules/${KERNEL_VERSION}/modules.order
>> ${nonarch_base_libdir}/modules/${KERNEL_VERSION}/modules.builtin"
>> -FILES_kernel-image = ""
>> -FILES_kernel-dev = "/boot/System.map* /boot/Module.symvers*
>> /boot/config* ${KERNEL_SRC_PATH}
>> ${nonarch_base_libdir}/modules/${KERNEL_VERSION}/build"
>> -FILES_kernel-vmlinux = "/boot/vmlinux-${KERNEL_VERSION_NAME}"
>> -FILES_kernel-modules = ""
>> -RDEPENDS_kernel = "kernel-base"
>> +FILES_${KERNEL_PACKAGE_NAME}-base =
>> "${nonarch_base_libdir}/modules/${KERNEL_VERSION}/modules.order
>> ${nonarch_base_libdir}/modules/${KERNEL_VERSION}/modules.builtin"
>> +FILES_${KERNEL_PACKAGE_NAME}-image = ""
>> +FILES_${KERNEL_PACKAGE_NAME}-dev = "/boot/System.map*
>> /boot/Module.symvers* /boot/config* ${KERNEL_SRC_PATH}
>> ${nonarch_base_libdir}/modules/${KERNEL_VERSION}/build"
>> +FILES_${KERNEL_PACKAGE_NAME}-vmlinux = "/boot/vmlinux-
>> ${KERNEL_VERSION_NAME}"
>> +FILES_${KERNEL_PACKAGE_NAME}-modules = ""
>> +RDEPENDS_${KERNEL_PACKAGE_NAME} = "${KERNEL_PACKAGE_NAME}-base"
>>   # Allow machines to override this dependency if kernel image files
>> are
>>   # not wanted in images as standard
>> -RDEPENDS_kernel-base ?= "kernel-image"
>> -PKG_kernel-image = "kernel-image-${@legitimize_package_name('${KERNE
>> L_VERSION}')}"
>> -RDEPENDS_kernel-image += "${@base_conditional('KERNEL_IMAGETYPE',
>> 'vmlinux', 'kernel-vmlinux', '', d)}"
>> -PKG_kernel-base = "kernel-${@legitimize_package_name('${KERNEL_VERSI
>> ON}')}"
>> -RPROVIDES_kernel-base += "kernel-${KERNEL_VERSION}"
>> -ALLOW_EMPTY_kernel = "1"
>> -ALLOW_EMPTY_kernel-base = "1"
>> -ALLOW_EMPTY_kernel-image = "1"
>> -ALLOW_EMPTY_kernel-modules = "1"
>> -DESCRIPTION_kernel-modules = "Kernel modules meta package"
>> -
>> -pkg_postinst_kernel-base () {
>> +RDEPENDS_${KERNEL_PACKAGE_NAME}-base ?= "${KERNEL_PACKAGE_NAME}-
>> image"
>> +PKG_${KERNEL_PACKAGE_NAME}-image = "${KERNEL_PACKAGE_NAME}-image-${@
>> legitimize_package_name('${KERNEL_VERSION}')}"
>> +RDEPENDS_${KERNEL_PACKAGE_NAME}-image += "${@base_conditional('KERNE
>> L_IMAGETYPE', 'vmlinux', '${KERNEL_PACKAGE_NAME}-vmlinux', '', d)}"
>> +PKG_${KERNEL_PACKAGE_NAME}-base = "${KERNEL_PACKAGE_NAME}-${@legitim
>> ize_package_name('${KERNEL_VERSION}')}"
>> +RPROVIDES_${KERNEL_PACKAGE_NAME}-base += "${KERNEL_PACKAGE_NAME}-
>> ${KERNEL_VERSION}"
>> +ALLOW_EMPTY_${KERNEL_PACKAGE_NAME} = "1"
>> +ALLOW_EMPTY_${KERNEL_PACKAGE_NAME}-base = "1"
>> +ALLOW_EMPTY_${KERNEL_PACKAGE_NAME}-image = "1"
>> +ALLOW_EMPTY_${KERNEL_PACKAGE_NAME}-modules = "1"
>> +DESCRIPTION_${KERNEL_PACKAGE_NAME}-modules = "Kernel modules meta
>> package"
>> +
>> +pkg_postinst_${KERNEL_PACKAGE_NAME}-base () {
>>   	if [ ! -e "$D/lib/modules/${KERNEL_VERSION}" ]; then
>>   		mkdir -p $D/lib/modules/${KERNEL_VERSION}
>>   	fi
>> @@ -521,7 +545,7 @@ pkg_postinst_kernel-base () {
>>   PACKAGESPLITFUNCS_prepend = "split_kernel_packages "
>>   
>>   python split_kernel_packages () {
>> -    do_split_packages(d, root='${nonarch_base_libdir}/firmware',
>> file_regex='^(.*)\.(bin|fw|cis|csp|dsp)$', output_pattern='kernel-
>> firmware-%s', description='Firmware for %s', recursive=True,
>> extra_depends='')
>> +    do_split_packages(d, root='${nonarch_base_libdir}/firmware',
>> file_regex='^(.*)\.(bin|fw|cis|csp|dsp)$',
>> output_pattern='${KERNEL_PACKAGE_NAME}-firmware-%s',
>> description='Firmware for %s', recursive=True, extra_depends='')
>>   }
>>   
>>   # Many scripts want to look in arch/$arch/boot for the bootable
>> @@ -604,21 +628,27 @@ MODULE_TARBALL_SYMLINK_NAME ?= "modules-
>> ${MACHINE}.tgz"
>>   MODULE_TARBALL_DEPLOY ?= "1"
>>   
>>   kernel_do_deploy() {
>> +	deployDir="${DEPLOYDIR}"
>> +	if [ -n "${KERNEL_DEPLOYSUBDIR}" ]; then
>> +		deployDir="${DEPLOYDIR}/${KERNEL_DEPLOYSUBDIR}"
>> +		mkdir "$deployDir"
>> +	fi
>> +
>>   	for type in ${KERNEL_IMAGETYPES} ; do
>>   		base_name=${type}-${KERNEL_IMAGE_BASE_NAME}
>> -		install -m 0644 ${KERNEL_OUTPUT_DIR}/${type}
>> ${DEPLOYDIR}/${base_name}.bin
>> +		install -m 0644 ${KERNEL_OUTPUT_DIR}/${type}
>> $deployDir/${base_name}.bin
>>   	done
>>   	if [ ${MODULE_TARBALL_DEPLOY} = "1" ] && (grep -q -i -e
>> '^CONFIG_MODULES=y$' .config); then
>>   		mkdir -p ${D}/lib
>> -		tar -cvzf ${DEPLOYDIR}/${MODULE_TARBALL_BASE_NAME}
>> -C ${D} lib
>> -		ln -sf ${MODULE_TARBALL_BASE_NAME}
>> ${DEPLOYDIR}/${MODULE_TARBALL_SYMLINK_NAME}
>> +		tar -cvzf $deployDir/${MODULE_TARBALL_BASE_NAME} -C
>> ${D} lib
>> +		ln -sf ${MODULE_TARBALL_BASE_NAME}
>> $deployDir/${MODULE_TARBALL_SYMLINK_NAME}
>>   	fi
>>   
>>   	for type in ${KERNEL_IMAGETYPES} ; do
>>   		base_name=${type}-${KERNEL_IMAGE_BASE_NAME}
>>   		symlink_name=${type}-${KERNEL_IMAGE_SYMLINK_NAME}
>> -		ln -sf ${base_name}.bin
>> ${DEPLOYDIR}/${symlink_name}.bin
>> -		ln -sf ${base_name}.bin ${DEPLOYDIR}/${type}
>> +		ln -sf ${base_name}.bin
>> $deployDir/${symlink_name}.bin
>> +		ln -sf ${base_name}.bin $deployDir/${type}
>>   	done
>>   
>>   	cd ${B}
>> @@ -628,8 +658,8 @@ kernel_do_deploy() {
>>   			echo "Copying deploy ${type} kernel-
>> initramfs image and setting up links..."
>>   			initramfs_base_name=${type}-
>> ${INITRAMFS_BASE_NAME}
>>   			initramfs_symlink_name=${type}-initramfs-
>> ${MACHINE}
>> -			install -m 0644
>> ${KERNEL_OUTPUT_DIR}/${type}.initramfs
>> ${DEPLOYDIR}/${initramfs_base_name}.bin
>> -			ln -sf ${initramfs_base_name}.bin
>> ${DEPLOYDIR}/${initramfs_symlink_name}.bin
>> +			install -m 0644
>> ${KERNEL_OUTPUT_DIR}/${type}.initramfs
>> $deployDir/${initramfs_base_name}.bin
>> +			ln -sf ${initramfs_base_name}.bin
>> $deployDir/${initramfs_symlink_name}.bin
>>   		fi
>>   	done
>>   }
>> diff --git a/meta/conf/documentation.conf
>> b/meta/conf/documentation.conf
>> index 35b9103b4a..e061b98de3 100644
>> --- a/meta/conf/documentation.conf
>> +++ b/meta/conf/documentation.conf
>> @@ -248,6 +248,7 @@ KERNEL_IMAGETYPE[doc] = "The type of kernel to
>> build for a device, usually set b
>>   KERNEL_IMAGETYPES[doc] = "The list of types of kernel to build for a
>> device, usually set by the machine configuration files and defaults
>> to KERNEL_IMAGETYPE."
>>   KERNEL_MODULE_AUTOLOAD[doc] = "Lists kernel modules that need to be
>> auto-loaded during boot"
>>   KERNEL_MODULE_PROBECONF[doc] = "Lists kernel modules for which the
>> build system expects to find module_conf_* values that specify
>> configuration for each of the modules"
>> +KERNEL_PACKAGE_NAME[doc] = "Name prefix for kernel packages.
>> Defaults to 'kernel'."
>>   KERNEL_PATH[doc] = "The location of the kernel sources. This
>> variable is set to the value of the STAGING_KERNEL_DIR within the
>> module class (module.bbclass)."
>>   KERNEL_SRC[doc] = "The location of the kernel sources. This variable
>> is set to the value of the STAGING_KERNEL_DIR within the module class
>> (module.bbclass)."
>>   KFEATURE_DESCRIPTION[doc] = "Provides a short description of a
>> configuration fragment. You use this variable in the .scc file that
>> describes a configuration fragment file."
>> diff --git a/meta/recipes-kernel/linux/linux-dtb.inc b/meta/recipes-
>> kernel/linux/linux-dtb.inc
>> index 0174c80d85..da6467bf9f 100644
>> --- a/meta/recipes-kernel/linux/linux-dtb.inc
>> +++ b/meta/recipes-kernel/linux/linux-dtb.inc
>> @@ -4,7 +4,7 @@ FILES_kernel-devicetree =
>> "/${KERNEL_IMAGEDEST}/devicetree*"
>>   PACKAGE_WRITE_DEPS += "virtual/update-alternatives-native"
>>   
>>   python __anonymous () {
>> -    d.appendVar("PACKAGES", " kernel-devicetree")
>> +    d.appendVar("PACKAGES", " ${KERNEL_PACKAGE_NAME}-devicetree")
>>   }
>>   
>>   normalize_dtb () {
>> diff --git a/meta/recipes-kernel/linux/linux-yocto.inc
>> b/meta/recipes-kernel/linux/linux-yocto.inc
>> index 637506a2a8..4e0ce029da 100644
>> --- a/meta/recipes-kernel/linux/linux-yocto.inc
>> +++ b/meta/recipes-kernel/linux/linux-yocto.inc
>> @@ -12,7 +12,7 @@ INC_PR = "r4"
>>   # PREFERRED_PROVIDER for virtual/kernel. This avoids network access
>> required
>>   # by the use of AUTOREV SRCREVs, which are the default for this
>> recipe.
>>   python () {
>> -    if d.getVar("PREFERRED_PROVIDER_virtual/kernel") !=
>> d.getVar("PN"):
>> +    if d.getVar("KERNEL_PACKAGE_NAME", True) == "kernel" and
>> d.getVar("PREFERRED_PROVIDER_virtual/kernel", True) != d.getVar("PN",
>> True):
>>           d.delVar("BB_DONT_CACHE")
>>           raise bb.parse.SkipPackage("Set
>> PREFERRED_PROVIDER_virtual/kernel to %s to enable it" %
>> (d.getVar("PN")))
>>   }