[yocto] [poky] Initramfs not appended to kernel image

[Wouter van Rooy]

Hello,

For the last week or so I have been struggling to build a kernel image with an embedded initramfs using the mechanisms provided by Poky Daisy. In local.conf I have set INITRAMFS_IMAGE_BUNDLE to "1" and INITRAMFS_IMAGE to the name of my image recipe. When I try to build virtual/kernel no errors are shown, but the resulting kernel image does not contain an initramfs either.

I have traced this issue to the passing of the $use_alternate_initrd variable in kernel.bbclass. The run.do_bundle_initramfs log contains the following snippets:

Lines 103..120:

do_bundle_initramfs() {
        if [ ! -z "sytxg1-bootmode-image" -a x"1" = x1 ]; then
                echo "Creating a kernel image with a bundled initramfs..."
                copy_initramfs
                if [ -e arch/powerpc/boot/uImage ] ; then
                        mv -f arch/powerpc/boot/uImage arch/powerpc/boot/uImage.bak
                fi
                use_alternate_initrd=CONFIG_INITRAMFS_SOURCE=/home/wouter/Source/Product/sytxg1-boot/tmp/work/sytxg1-oe-linux/linux-axon/3.10-9/linux-3.10.9/usr/sytxg1-bootmode-image-sytxg1.cpio
                kernel_do_compile
                mv -f arch/powerpc/boot/uImage arch/powerpc/boot/uImage.initramfs
                mv -f arch/powerpc/boot/uImage.bak arch/powerpc/boot/uImage
                # Update install area
                echo "There is kernel image bundled with initramfs: /home/wouter/Source/Product/sytxg1-boot/tmp/work/sytxg1-oe-linux/linux-axon/3.10-9/linux-3.10.9/arch/powerpc/boot/uImage.initramfs"
                install -m 0644 /home/wouter/Source/Product/sytxg1-boot/tmp/work/sytxg1-oe-linux/linux-axon/3.10-9/linux-3.10.9/arch/powerpc/boot/uImage.initramfs /home/wouter/Source/Product/sytxg1-boot/tmp/work/sytxg1-oe-linux/linux-axon/3.10-9/image/boot/uImage-initramfs-sytxg1.bin
                echo "/home/wouter/Source/Product/sytxg1-boot/tmp/work/sytxg1-oe-linux/linux-axon/3.10-9/linux-3.10.9/arch/powerpc/boot/uImage.initramfs"
        fi
 
}

Lines 164..171:

kernel_do_compile() {
        unset CFLAGS CPPFLAGS CXXFLAGS LDFLAGS MACHINE
        oe_runmake uImage  CC="powerpc-oe-linux-gcc " LD="powerpc-oe-linux-ld.bfd "
        if test "uImage.gz" = "uImage"; then
                gzip -9c < "uImage" > "arch/powerpc/boot/uImage"
        fi
 
}

So, it seems that although do_bundle_initramfs() sets the $use_alternate_initrd to the correct value it is not passed in the oe_runmake call in kernel_do_compile(). Judging from the contents of kernel.bbclass I would expect it to be appended after the LD="..." statement. For now I have found a workaround by copying the relevant oe_runmake call to do_bundle_initramfs(). The patch is included below.

I cannot imagine this is the intended way to make things work. Could anyone please shed some light on what I am doing wrong in this matter?

Kind regards,

Wouter van Rooy


diff --git a/meta/classes/kernel.bbclass b/meta/classes/kernel.bbclass
index 19b159b..224e01e 100644
--- a/meta/classes/kernel.bbclass
+++ b/meta/classes/kernel.bbclass
@@ -131,8 +131,11 @@ do_bundle_initramfs () {
 		if [ -e ${KERNEL_OUTPUT} ] ; then
 			mv -f ${KERNEL_OUTPUT} ${KERNEL_OUTPUT}.bak
 		fi
-		use_alternate_initrd=CONFIG_INITRAMFS_SOURCE=${B}/usr/${INITRAMFS_IMAGE}-${MACHINE}.cpio
-		kernel_do_compile
+		unset CFLAGS CPPFLAGS CXXFLAGS LDFLAGS MACHINE
+		oe_runmake ${KERNEL_IMAGETYPE_FOR_MAKE} ${KERNEL_ALT_IMAGETYPE} CC="${KERNEL_CC}" LD="${KERNEL_LD}" ${KERNEL_EXTRA_ARGS} CONFIG_INITRAMFS_SOURCE=${B}/usr/${INITRAMFS_IMAGE}-${MACHINE}.cpio
+		if test "${KERNEL_IMAGETYPE_FOR_MAKE}.gz" = "${KERNEL_IMAGETYPE}"; then
+			gzip -9c < "${KERNEL_IMAGETYPE_FOR_MAKE}" > "${KERNEL_OUTPUT}"
+		fi
 		mv -f ${KERNEL_OUTPUT} ${KERNEL_OUTPUT}.initramfs
 		mv -f ${KERNEL_OUTPUT}.bak ${KERNEL_OUTPUT}
 		# Update install area
@@ -150,20 +153,7 @@ addtask bundle_initramfs after do_install before do_deploy
 
 kernel_do_compile() {
 	unset CFLAGS CPPFLAGS CXXFLAGS LDFLAGS MACHINE
-	# The $use_alternate_initrd is only set from
-	# do_bundle_initramfs() This variable is specifically for the
-	# case where we are making a second pass at the kernel
-	# compilation and we want to force the kernel build to use a
-	# different initramfs image.  The way to do that in the kernel
-	# is to specify:
-	# make ...args... CONFIG_INITRAMFS_SOURCE=some_other_initramfs.cpio
-	if [ "$use_alternate_initrd" = "" ] && [ "${INITRAMFS_TASK}" != "" ] ; then
-		# The old style way of copying an prebuilt image and building it
-		# is turned on via INTIRAMFS_TASK != ""
-		copy_initramfs
-		use_alternate_initrd=CONFIG_INITRAMFS_SOURCE=${B}/usr/${INITRAMFS_IMAGE}-${MACHINE}.cpio
-	fi
-	oe_runmake ${KERNEL_IMAGETYPE_FOR_MAKE} ${KERNEL_ALT_IMAGETYPE} CC="${KERNEL_CC}" LD="${KERNEL_LD}" ${KERNEL_EXTRA_ARGS} $use_alternate_initrd
+	oe_runmake ${KERNEL_IMAGETYPE_FOR_MAKE} ${KERNEL_ALT_IMAGETYPE} CC="${KERNEL_CC}" LD="${KERNEL_LD}" ${KERNEL_EXTRA_ARGS}
 	if test "${KERNEL_IMAGETYPE_FOR_MAKE}.gz" = "${KERNEL_IMAGETYPE}"; then
 		gzip -9c < "${KERNEL_IMAGETYPE_FOR_MAKE}" > "${KERNEL_OUTPUT}"
 	fi