Benefits of Kirkstone:

• There are 93 Security Fixes

  https://docs.yoctoproject.org/migration-guides/release-notes-4.0.html#security-fixes-in-4-0

• Components where security fixes are added :- binutils, curl, epiphany, expat, ffmpeg, gcc, glibc, gmp, go, grub2, gzip, libarchive, libxml2, libxslt, lighttpd, linux-yocto, amdgpu, lua, openssl, qemu , rpm , seatd , speex , squashfs-tools , systemd , tiff , unzip , vim , virglrenderer , webkitgtk , xz , zlib

• There are 318 opensource component version upgrades

https://docs.yoctoproject.org/migration-guides/release-notes-4.0.html#recipe-upgrades-in-4-0

• Major opensource upgrades (Dunfell → Kirkstone) are :- GCC (9.3 → 11.3) , glibc (2.31 → 2.35) , glib-2.0 (2.62.4 → 2.72.3), systemd (244.3 → 250.5) , busybox (1.31.1 → 1.35.0)

• Netflix upgrade, youtube

• GCC compiler

• Maintainability - Dunfell 4 years ; Kirkstone 2 years ; CVE Dunfell is sill open (Refer Yocto mailing list), Upstream dunfell 3.1.24 has open CVE

• Build time - reduce number of default dependency (make build faster in first/second time)

• meta-rust is in core

• software bill of material (security infrastructure)

• share state - c standard. faster sstsate performance due to decompression standard cstd (twice faster than xz)

• license management tool improvement (more accurate license compliance)

• Kirkstone need minimum 4.x kernel (refer systemd)

• linux_kernel_header does not mandate

      Reference :- https://docs.yoctoproject.org/migration-guides/release-notes-4.0.html 
      Reference :-https://code.rdkcentral.com/r/plugins/gitiles/manifests/+/refs/heads/kirkstone/oe-layers.xml (Kirkstone specific OE layers )
      

RPI4 Kirkstone build instructions

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