diff mbox series

[v3] genericarm64 core-image-initramfs-boot: remove some kernel drivers

Message ID 20260413072715.20701-1-mikko.rapeli@linaro.org (mailing list archive)
State New
Headers show
Series [v3] genericarm64 core-image-initramfs-boot: remove some kernel drivers | expand

Commit Message

Mikko Rapeli April 13, 2026, 7:27 a.m. UTC 
genericarm64 supports a lot of HW and thus large collection of kernel
drivers are enabled and installed to images by default.
Subset of the kernel drivers are needed in initramfs to mount rootfs
from local mass storage devices. This increases initramfs size a lot
and with new kernel config updates even more. Thus remove kernel
drivers from initramfs image which are not needed for mounting
rootfs from local mass storage devices. GPU, Bluetooth, NFC,
sound, networking etc support is not needed in the initramfs.

According to buildhistory core-image-initramfs-boot size is reduced
from 118 to 83 Mb.

Signed-off-by: Mikko Rapeli <mikko.rapeli@linaro.org>
---
 .../images/core-image-initramfs-boot.bbappend | 28 +++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 meta-yocto-bsp/recipes-core/images/core-image-initramfs-boot.bbappend

v3: added PATHS_TO_REMOVE variable so that it can be customized
    as suggested by Jose Quaresma <quaresma.jose@gmail.com>

v2: https://lists.yoctoproject.org/g/poky/message/13894
diff mbox series

Patch

diff --git a/meta-yocto-bsp/recipes-core/images/core-image-initramfs-boot.bbappend b/meta-yocto-bsp/recipes-core/images/core-image-initramfs-boot.bbappend
new file mode 100644
index 000000000000..2298c2f94740
--- /dev/null
+++ b/meta-yocto-bsp/recipes-core/images/core-image-initramfs-boot.bbappend
@@ -0,0 +1,28 @@ 
+POSTFUNCS = ""
+POSTFUNCS:genericarm64 = "reduce_initrd_size"
+
+PATHS_TO_REMOVE = ""
+# these kernel modules are not needed for rootfs mount from local mass storage
+# and can be loaded from main rootfs by udev
+PATHS_TO_REMOVE:genericarm64 = "\
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/drivers/bluetooth \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/drivers/gpu \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/drivers/media \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/drivers/net \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/drivers/nfc \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/drivers/usb/gadget \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/fs/fuse \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/net/bluetooth \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/net/bridge \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/net/netfilter \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/net/nfc \
+    ${WORKDIR}/rootfs/${libdir}/modules/*/kernel/sound \
+"
+
+do_rootfs[postfuncs] += "${POSTFUNCS}"
+reduce_initrd_size () {
+    if [ -n "${PATHS_TO_REMOVE}" ]; then
+        rm -rf ${PATHS_TO_REMOVE}
+    fi
+}
+