Re: [PATCH v4] kernel: Add support for multiple kernel packages

["Wold, Saul" <saul.wold@intel.com>]

On Wed, 2017-07-05 at 12:33 -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 thread:
> http://lists.openembedded.org/pipermail/openembedded-core/2015-Decemb
> er/thread.html#114122
> 
> 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.

So I finally had a chance to get back to this and test build with it, I
saw the following WARNING, which lead to the ERROR:

WARNING: Variable key FILES_${PN}-dev (${includedir} ${FILES_SOLIBSDEV}
${libdir}/*.la ${libdir}/*.o ${libdir}/pkgconfig ${datadir}/pkgconfig
${datadir}/aclocal ${base_libdir}/*.o ${libdir}/${BPN}/*.la
${base_libdir}/*.la) replaces original key FILES_linux-yocto-dev
(/boot/System.map* /boot/Module.symvers* /boot/config*
${KERNEL_SRC_PATH}
${nonarch_base_libdir}/modules/${KERNEL_VERSION}/build).
ERROR: linux-yocto-4.10.17+gitAUTOINC+e92bd55409_6648a34e00-r0
do_package: QA Issue: linux-yocto: Files/directories were installed but
not shipped in any package:
  /boot/System.map-4.10.17-yocto-standard
  /boot/Module.symvers-4.10.17-yocto-standard
  /boot/config-4.10.17-yocto-standard
Please set FILES such that these items are packaged. Alternatively if
they are unneeded, avoid installing them or delete them within
do_install.
linux-yocto: 3 installed and not shipped files. [installed-vs-shipped]
ERROR: linux-yocto-4.10.17+gitAUTOINC+e92bd55409_6648a34e00-r0
do_package: Fatal QA errors found, failing task.
ERROR: linux-yocto-4.10.17+gitAUTOINC+e92bd55409_6648a34e00-r0
do_package: Function failed: do_package

Something seems to be causing the FILES_linux-yocto-dev info to be
overridden, I have not tracked down the culprit yet.

Sau!

> ---
>  meta/classes/kernel-module-split.bbclass  |  9 ++--
>  meta/classes/kernel.bbclass               | 85 ++++++++++++++++++---
> ----------
>  meta/conf/documentation.conf              |  1 +
>  meta/recipes-kernel/linux/linux-dtb.inc   |  2 +-
>  meta/recipes-kernel/linux/linux-yocto.inc |  2 +-
>  5 files changed, 59 insertions(+), 40 deletions(-)
> 
> diff --git a/meta/classes/kernel-module-split.bbclass
> b/meta/classes/kernel-module-split.bbclass
> index 1035525dac..9716c5937b 100644
> --- a/meta/classes/kernel-module-split.bbclass
> +++ b/meta/classes/kernel-module-split.bbclass
> @@ -30,7 +30,7 @@ do_install_append() {
>  
>  PACKAGESPLITFUNCS_prepend = "split_kernel_module_packages "
>  
> -KERNEL_MODULES_META_PACKAGE ?= "kernel-modules"
> +KERNEL_MODULES_META_PACKAGE ?= "${KERNEL_PACKAGE_NAME}-modules"
>  
>  KERNEL_MODULE_PACKAGE_PREFIX ?= ""
>  KERNEL_MODULE_PACKAGE_SUFFIX ?= "-${KERNEL_VERSION}"
> @@ -129,16 +129,19 @@ 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='${nonarch_base_libdir}/modules', file_regex=module_regex,
> output_pattern=module_pattern, description='%s kernel module',
> postinst=postinst, postrm=postrm, recursive=True, hook=frob_metadata,
> extra_depends='%s-%s' % (kernel_package_name, kernel_version))
>      if modules:
>          metapkg = d.getVar('KERNEL_MODULES_META_PACKAGE')
>          d.appendVar('RDEPENDS_' + metapkg, ' '+' '.join(modules))
> diff --git a/meta/classes/kernel.bbclass
> b/meta/classes/kernel.bbclass
> index 7670c7107a..7fa4509961 100644
> --- a/meta/classes/kernel.bbclass
> +++ b/meta/classes/kernel.bbclass
> @@ -1,6 +1,8 @@
>  inherit linux-kernel-base kernel-module-split
>  
> -PROVIDES += "virtual/kernel"
> +KERNEL_PACKAGE_NAME ??= "kernel"
> +
> +PROVIDES += "${@ "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"
>  
> @@ -33,10 +35,23 @@ KERNEL_VERSION_PKG_NAME[vardepvalue] =
> "${LINUX_VERSION}"
>  
>  python __anonymous () {
>  
> +    # 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 ${WORKDIR} in
> alternate
> +    # kernel recipes (I.e. where KERNEL_PACKAGE_NAME != kernel) so
> that they
> +    # may build in parallel with the default kernel without
> clobbering.
> +    if d.getVar("KERNEL_PACKAGE_NAME", True) != "kernel":
> +        workdir = d.getVar("WORKDIR", True)
> +        sourceDir = os.path.join(workdir, 'kernel-source')
> +        artifactsDir = os.path.join(workdir, 'kernel-build-
> artifacts')
> +        d.setVar("STAGING_KERNEL_DIR", sourceDir)
> +        d.setVar("STAGING_KERNEL_BUILDDIR", artifactsDir)
> +
>      # Merge KERNEL_IMAGETYPE and KERNEL_ALT_IMAGETYPE into
> KERNEL_IMAGETYPES
>      type = d.getVar('KERNEL_IMAGETYPE') or ""
>      alttype = d.getVar('KERNEL_ALT_IMAGETYPE') or ""
>      types = d.getVar('KERNEL_IMAGETYPES') or ""
> +    kname = d.getVar('KERNEL_PACKAGE_NAME', True) or "kernel"
>      if type not in types.split():
>          types = (type + ' ' + types).strip()
>      if alttype not in types.split():
> @@ -53,22 +68,22 @@ python __anonymous () {
>          typelower = type.lower()
>          imagedest = d.getVar('KERNEL_IMAGEDEST')
>  
> -        d.appendVar('PACKAGES', ' ' + 'kernel-image-' + typelower)
> +        d.appendVar('PACKAGES', ' %s-image-%s' % (kname, typelower))
>  
> -        d.setVar('FILES_kernel-image-' + typelower, '/' + imagedest
> + '/' + type + '-${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 +141,9 @@ 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 +386,9 @@ 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-${KERNEL_VERSION}
>  }
>  
>  PACKAGEFUNCS += "emit_depmod_pkgdata"
> @@ -388,7 +403,7 @@ do_shared_workdir () {
>  	# Store the kernel version in sysroots for module-
> base.bbclass
>  	#
>  
> -	echo "${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 +501,28 @@ 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 +536,7 @@ 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
> 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")))
>  }