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authorAndrew Geissler <geissonator@yahoo.com>2021-06-25 22:25:14 +0300
committerBrad Bishop <bradleyb@fuzziesquirrel.com>2021-06-28 15:35:59 +0300
commit0903674e2d7bafcf89cf75adbcf34cac5ce4b938 (patch)
treec46ac7b80c4e559224df62f95931ed8a2ab51435 /poky/documentation/migration-guides/migration-2.5.rst
parenta1a6aefba3ae965f2447b102663b2a6a40aa968a (diff)
downloadopenbmc-0903674e2d7bafcf89cf75adbcf34cac5ce4b938.tar.xz
poky: subtree update:9d1b332292..2834c2f853
Alex Stewart (3): opkg-utils: upgrade to version 0.4.5 opkg: upgrade to version 0.4.5 opkg: add QA check for openssl feed verification Alexander Kanavin (37): virglrenderer: explicitly depend on libgbm elfutils: update 0.183 -> 0.185 libcap: update 2.49 -> 2.50 perl: split perl-cross into its own recipe perl-cross: 1.3.5 -> 1.3.6 perl: update 5.32.1 -> 5.34.0 libgcrypt: upgrade 1.9.2 -> 1.9.3 erofs-utils: correct upstream version check m4: correct ptest failures ovmf: update 2021.02 -> 2021.05 apt: update 2.2.3 -> 2.2.4 util-linux: update 2.36.2 -> 2.37 cross-canadian: correct the location of pkg-config files nettle: update 3.7.2 -> 3.7.3 glib-2.0: update 2.68.2 -> 2.68.3 meson: upgrade 0.58.0 -> 0.58.1 ell: upgrade 0.40 -> 0.41 erofs-utils: upgrade 1.2.1 -> 1.3 grub: upgrade 2.04+2.06~rc1 -> 2.06 gptfdisk: upgrade 1.0.7 -> 1.0.8 connman: update 1.39 -> 1.40 libksba: upgrade 1.5.1 -> 1.6.0 libnss-mdns: upgrade 0.15 -> 0.15.1 libwpe: upgrade 1.10.0 -> 1.10.1 puzzles: upgrade to latest revision rng-tools: upgrade 6.12 -> 6.13 stress-ng: upgrade 0.12.09 -> 0.12.10 python3-magic: upgrade 0.4.23 -> 0.4.24 sudo: upgrade 1.9.7 -> 1.9.7p1 wpebackend-fdo: upgrade 1.8.4 -> 1.10.0 xkeyboard-config: upgrade 2.32 -> 2.33 bitbake.conf: enable debuginfod in native/nativesdk gdb-cross: enable debuginfod util-linux: backport a patch to address mkswap hangs selftest: do not hardcode /tmp/sdk glibc: do not enable memory tagging on aarch64 just yet mesa: enable gallium intel drivers when building for x86 Alexandre Belloni (1): runqemu: time the copy to tmpfs Alexey Brodkin (3): gcc: Fixes for ARC gdb: Add native GDB support for ARC gcc: Apply multilib fix to ARC as well Alistair Francis (3): recipes-bsp/opensbi: Disable FW_PIC recipes-bsp/u-boot: Allow deploying the u-boot DTB recipes-bsp/opensbi: Add support for specifying a device tree Anders Wallin (1): coreutils: remove NOSTAT_LEAF_OPTIMIZATION Andrea Adami (1): kernel.bbclass: fix do_sizecheck() comparison Andreas Müller (19): mesa: upgrade 21.1.1 -> 21.1.2 systemd: Add more ugly casts to fix build with musl alsa-lib: upgrade 1.2.4 -> 1.2.5 alsa-plugins: upgrade 1.2.2 -> 1.2.5 alsa-tools: upgrade 1.2.2 -> 1.2.5 alsa-topology-conf: upgrade 1.2.4 -> 1.2.5 alsa-ucm-conf: upgrade 1.2.4 -> 1.2.5 alsa-utils(-scripts): upgrade 1.2.4 -> 1.2.5 libinput: upgrade 1.17.3 -> 1.18.0 xf86-input-libinput: upgrade 0.30.0 -> 1.0.1 epiphany: upgrade 40.1 -> 40.2 vala: upgrade 0.52.3 -> 0.52.4 p11-kit: upgrade 0.23.22 -> 0.23.24 xorgproto: upgrade 2021.4.99.1 -> 2021.4.99.2 mpg123: 1.27.2 -> 1.28.0 libx11: upgrade 1.7.1 -> 1.7.2 libx11: remove CPPFLAGS_FOR_BUILD += "-D_GNU_SOURCE" libpcap: upgrade 1.10.0 -> 1.10.1 mesa: upgrade 21.1.2 -> 21.1.3 Bruce Ashfield (10): linux-yocto/5.10: update to v5.10.42 linux-yocto/5.10: temporarily revert aufs linux-yocto-dev: base AUTOREV on specified version linux-yocto/5.4: update to v5.4.124 linux-yocto/5.10: restore aufs linux-yocto/5.10: update to v5.10.43 linux-yocto/5.4: update to v5.4.125 linux-yocto/5.10: cgroup1: fix leaked context root causing sporadic NULL deref in LTP btrfs-tools: include linux/const.h to fix build with 5.12+ headers bsps/5.10: update to v5.10.43 Changqing Li (1): libjpeg-turbo: fix do_compile error on arm Chris Laplante (1): bitbake: build: warn on setting noexec/nostamp/fakeroot flag to any value besides '1' Daniel Wagenknecht (5): ref-manual: variables: update examples refering to DEPLOY_DIR_IMAGE ref-manual: variables: document IMGDEPLOYDIR ref-manual: migration-2.2: add note about IMGDEPLOYDIR ref-manual: variables: fixup example in IMAGE_CMD ref-manual: variables: fixup class reference in IMAGE_MANIFEST Joe Slater (1): tcf-agent: change license to EPL/EDL Joshua Watt (2): classes/buildhistory: Add option to strip path prefix classes/reproducible_build: Use atomic rename for SDE file Justin Bronder (1): populate_sdk_ext: copy BBMULTICONFIG files Kai Kang (1): valgrind: fix a typo Khem Raj (14): harfbuzz: Fix unused-variable warning arch-armv4: Allow -march=armv4 ffmpeg: Link in libatomic on riscv32 libssp-nonshared: Use a different implementation for __stack_chk_fail qemuriscv: Enable 4 core emulation gcompat: Add recipe musl: Do not package glibc loader musl: Set UPSTREAM_CHECK_COMMITS Revert "libgcc-initial: Do not build fp128 to decimal ppc functions" qemu: Provide float128 via hwcaps2 on ppc64le linuxloader: Be aware of riscv32 ldso linuxloader.bbclass: Add entry for ppc64 LE glibc loader gcompat: Create symlinks to glibc ldso locations sdk: Enable do_populate_sdk with multilibs Luca Boccassi (1): systemd: install new sysext tool via systemd-extra-utils Marcus Comstedt (1): conf/machine-sdk: Add ppc64 SDK machine Matt Spencer (1): systemd-conf: Prevent systemd-network from managing veth interfaces Michael Halstead (1): releases: update to include 3.1.8 Michael Opdenacker (12): bitbake: docs: Add BB_HASHSERVE definition to glossary bitbake: doc: bitbake-user-manual: fix erroneous statement in glossary intro manuals: fix epub export warnings ref-manual: move migration guides to separate document releases: clarify supported and outdated releases releases: put release number after "Release Series" sdk-manual: fix broken references migration guides: remove index reference to BB_SETSCENE_VERIFY_FUNCTION2 manuals: fix issues related to trailing dots sdk-manual: add missing quoting around "devtool upgrade" sdk-manual: fix wrong word sdk-manual: add missing index references Ming Liu (2): u-boot-tools: fix a mkimage signature issue uboot-sign.bbclass: fix some install commands Mingli Yu (2): sysstat: make the service start automatically boost: fix wrong type for mutex in regex v5 Nicolas Dechesne (3): index: remove the link/section to 'mega manual' from main page index: remove links to releases manual and index index: split releases manuals and indexes into two sections in the tree Paul Barker (2): bitbake: asyncrpc: Add ping method bitbake: asyncrpc: Reduce verbosity Quentin Schulz (6): docs: ref-manual: migration-3.0: remove reference to non-existing BB_SETSCENE_VERIFY_FUNCTION2 docs: ref-manual: variables: add missing links to terms glossary bitbake: doc: user-manual: remove mentions to BBVERSIONS bitbake: doc: user-manual: ref-manual: remove mentions to BB_SETSCENE_VERIFY_FUNCTION2 documentation: Makefile: turn warnings into errors by default docs: replace ``FOO`` by :term:`FOO` where possible Richard Purdie (11): lttng-tools: upgrade 2.12.3 -> 2.12.4 qemurunner: Try to ensure mmap'd libs are paged in qemurunner: Increase startup timeout 120 -> 300 build-appliance-image: Update to master head revision test-manual: add initial reproducible builds documentation test-manual: Add initial YP Compatible documentation README: Tweak as the website isn't really new now README: Move to using markdown as the format perf: Use python3targetconfig to ensure we use target libraries ltp: Reinstate 'hanging' tests for evaluation README.poky: Formatting and content cleanup Richard Weinberger (1): Document erofs filesystem targets Robert P. J. Day (2): ref-manual: add SRCTREECOVEREDTASKS to variable glossary ref-manual: add glossary entry for NON_MULTILIB_RECIPES Ross Burton (11): mx: remove from Openembedded Core core-image-weston: remove Clutter examples Remove Clutter and Cogl oeqa: remove Clutter usage meta-poky: remove clutter references Remove Clutter references gcc: enable branch protection by standard image_types: add zsync conversions avahi: apply fix for CVE-2021-3468 qemu: fix virtio vhost-user-gpu CVEs gcc: replace gdb helper install revert with the upstream fix Sakib Sajal (3): oeqa/core/target/qemu.py: display contents of dumped files oe-time-dd-test.sh: improve output formatting oe-time-dd-test.sh: add iostat command Saul Wold (1): qemurunner: add second qmp port Scott Weaver (1): bitbake: fetch2: add check for empty SRC_URI hash string Tim Orling (8): maintainers.inc: update email address python3-scons: upgrade 3.1.2 -> 4.1.0; simplify python3-hypothesis: upgrade 6.13.7 -> 6.13.14 at-spi2-core: upgrade 2.40.1 -> 2.40.2 python3-importlib-metadata: upgrade 4.4.0 -> 4.5.0 python3-manifest: add statistics subpackage python3-hypothesis: upgrade 6.13.14 -> 6.14.0 python3: skip tests requiring tools-sdk Tony Battersby (1): glibc: fix path to place zdump in the tzcode package Tony Tascioglu (3): valgrind: Improve non-deterministic ptest reliability valgrind: remove buggy ptest from arm64 valgrind: Actually install list of non-deterministic ptests hongxu (1): nativesdk-libdnf: fix installed and not shipped files wangmy (21): cmake: upgrade 3.20.2 -> 3.20.3 mtools: upgrade 4.0.27 -> 4.0.29 python3-magic: upgrade 0.4.22 -> 0.4.23 less: upgrade 586 -> 589 python3-libarchive-c: upgrade 3.0 -> 3.1 diffoscope: upgrade 175 -> 177 dtc: upgrade 1.6.0 -> 1.6.1 git: upgrade 2.31.1 -> 2.32.0 gnutls: upgrade 3.7.1 -> 3.7.2 go: upgrade 1.16.4 -> 1.16.5 less: upgrade 589 -> 590 ethtool: upgrade 5.10 -> 5.12 m4: upgrade 1.4.18 -> 1.4.19 alsa-lib: upgrade 1.2.5 -> 1.2.5.1 alsa-utils: upgrade 1.2.5 -> 1.2.5.1 alsa-topology-conf: upgrade 1.2.5 -> 1.2.5.1 alsa-ucm-conf: upgrade 1.2.5 -> 1.2.5.1 blktrace: upgrade 1.2.0 -> 1.3.0 enchant2: upgrade 2.2.15 -> 2.3.0 librepo: upgrade 1.14.0 -> 1.14.1 createrepo-c: upgrade 0.17.2 -> 0.17.3 zangrc (1): python3-pycairo: upgrade 1.20.0 -> 1.20.1 zhengruoqin (6): python3-importlib-metadata: upgrade 4.3.0 -> 4.4.0 libogg: upgrade 1.3.4 -> 1.3.5 liburcu: upgrade 0.12.2 -> 0.13.0 libcomps: upgrade 0.1.16 -> 0.1.17 python3-dbusmock: upgrade 0.23.0 -> 0.23.1 nfs-utils: upgrade 2.5.3 -> 2.5.4 Signed-off-by: Andrew Geissler <geissonator@yahoo.com> Change-Id: Iac124e214336beb9cab7fb3b67a6968d4e34d06f
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+Release 2.5 (sumo)
+==================
+
+This section provides migration information for moving to the Yocto
+Project 2.5 Release (codename "sumo") from the prior release.
+
+.. _migration-2.5-packaging-changes:
+
+Packaging Changes
+-----------------
+
+This section provides information about packaging changes that have
+occurred:
+
+- ``bind-libs``: The libraries packaged by the bind recipe are in a
+ separate ``bind-libs`` package.
+
+- ``libfm-gtk``: The ``libfm`` GTK+ bindings are split into a
+ separate ``libfm-gtk`` package.
+
+- ``flex-libfl``: The flex recipe splits out libfl into a separate
+ ``flex-libfl`` package to avoid too many dependencies being pulled in
+ where only the library is needed.
+
+- ``grub-efi``: The ``grub-efi`` configuration is split into a
+ separate ``grub-bootconf`` recipe. However, the dependency
+ relationship from ``grub-efi`` is through a virtual/grub-bootconf
+ provider making it possible to have your own recipe provide the
+ dependency. Alternatively, you can use a BitBake append file to bring
+ the configuration back into the ``grub-efi`` recipe.
+
+- *armv7a Legacy Package Feed Support:* Legacy support is removed for
+ transitioning from ``armv7a`` to ``armv7a-vfp-neon`` in package
+ feeds, which was previously enabled by setting
+ ``PKGARCHCOMPAT_ARMV7A``. This transition occurred in 2011 and active
+ package feeds should by now be updated to the new naming.
+
+.. _migration-2.5-removed-recipes:
+
+Removed Recipes
+---------------
+
+The following recipes have been removed:
+
+- ``gcc``: The version 6.4 recipes are replaced by 7.x.
+
+- ``gst-player``: Renamed to ``gst-examples`` as per upstream.
+
+- ``hostap-utils``: This software package is obsolete.
+
+- ``latencytop``: This recipe is no longer maintained upstream. The
+ last release was in 2009.
+
+- ``libpfm4``: The only file that requires this recipe is
+ ``oprofile``, which has been removed.
+
+- ``linux-yocto``: The version 4.4, 4.9, and 4.10 recipes have been
+ removed. Versions 4.12, 4.14, and 4.15 remain.
+
+- ``man``: This recipe has been replaced by modern ``man-db``
+
+- ``mkelfimage``: This tool has been removed in the upstream coreboot
+ project, and is no longer needed with the removal of the ELF image
+ type.
+
+- ``nativesdk-postinst-intercept``: This recipe is not maintained.
+
+- ``neon``: This software package is no longer maintained upstream
+ and is no longer needed by anything in OpenEmbedded-Core.
+
+- ``oprofile``: The functionality of this recipe is replaced by
+ ``perf`` and keeping compatibility on an ongoing basis with ``musl``
+ is difficult.
+
+- ``pax``: This software package is obsolete.
+
+- ``stat``: This software package is not maintained upstream.
+ ``coreutils`` provides a modern stat binary.
+
+- ``zisofs-tools-native``: This recipe is no longer needed because
+ the compressed ISO image feature has been removed.
+
+.. _migration-2.5-scripts-and-tools-changes:
+
+Scripts and Tools Changes
+-------------------------
+
+The following are changes to scripts and tools:
+
+- ``yocto-bsp``, ``yocto-kernel``, and ``yocto-layer``: The
+ ``yocto-bsp``, ``yocto-kernel``, and ``yocto-layer`` scripts
+ previously shipped with poky but not in OpenEmbedded-Core have been
+ removed. These scripts are not maintained and are outdated. In many
+ cases, they are also limited in scope. The
+ ``bitbake-layers create-layer`` command is a direct replacement for
+ ``yocto-layer``. See the documentation to create a BSP or kernel
+ recipe in the ":ref:`bsp-guide/bsp:bsp kernel recipe example`" section.
+
+- ``devtool finish``: ``devtool finish`` now exits with an error if
+ there are uncommitted changes or a rebase/am in progress in the
+ recipe's source repository. If this error occurs, there might be
+ uncommitted changes that will not be included in updates to the
+ patches applied by the recipe. A -f/--force option is provided for
+ situations that the uncommitted changes are inconsequential and you
+ want to proceed regardless.
+
+- ``scripts/oe-setup-rpmrepo`` script: The functionality of
+ ``scripts/oe-setup-rpmrepo`` is replaced by
+ ``bitbake package-index``.
+
+- ``scripts/test-dependencies.sh`` script: The script is largely made
+ obsolete by the recipe-specific sysroots functionality introduced in
+ the previous release.
+
+.. _migration-2.5-bitbake-changes:
+
+BitBake Changes
+---------------
+
+The following are BitBake changes:
+
+- The ``--runall`` option has changed. There are two different
+ behaviors people might want:
+
+ - *Behavior A:* For a given target (or set of targets) look through
+ the task graph and run task X only if it is present and will be
+ built.
+
+ - *Behavior B:* For a given target (or set of targets) look through
+ the task graph and run task X if any recipe in the taskgraph has
+ such a target, even if it is not in the original task graph.
+
+ The ``--runall`` option now performs "Behavior B". Previously
+ ``--runall`` behaved like "Behavior A". A ``--runonly`` option has
+ been added to retain the ability to perform "Behavior A".
+
+- Several explicit "run this task for all recipes in the dependency
+ tree" tasks have been removed (e.g. ``fetchall``, ``checkuriall``,
+ and the ``*all`` tasks provided by the ``distrodata`` and
+ ``archiver`` classes). There is a BitBake option to complete this for
+ any arbitrary task. For example::
+
+ bitbake <target> -c fetchall
+
+ should now be replaced with::
+
+ bitbake <target> --runall=fetch
+
+.. _migration-2.5-python-and-python3-changes:
+
+Python and Python 3 Changes
+---------------------------
+
+The following are auto-packaging changes to Python and Python 3:
+
+The script-managed ``python-*-manifest.inc`` files that were previously
+used to generate Python and Python 3 packages have been replaced with a
+JSON-based file that is easier to read and maintain. A new task is
+available for maintainers of the Python recipes to update the JSON file
+when upgrading to new Python versions. You can now edit the file
+directly instead of having to edit a script and run it to update the
+file.
+
+One particular change to note is that the Python recipes no longer have
+build-time provides for their packages. This assumes ``python-foo`` is
+one of the packages provided by the Python recipe. You can no longer run
+``bitbake python-foo`` or have a
+:term:`DEPENDS` on ``python-foo``,
+but doing either of the following causes the package to work as
+expected::
+
+ IMAGE_INSTALL_append = " python-foo"
+
+or ::
+
+ RDEPENDS_${PN} = "python-foo"
+
+The earlier build-time provides behavior was a quirk of the
+way the Python manifest file was created. For more information on this
+change please see :yocto_git:`this commit
+</poky/commit/?id=8d94b9db221d1def42f091b991903faa2d1651ce>`.
+
+.. _migration-2.5-miscellaneous-changes:
+
+Miscellaneous Changes
+---------------------
+
+The following are additional changes:
+
+- The ``kernel`` class supports building packages for multiple kernels.
+ If your kernel recipe or ``.bbappend`` file mentions packaging at
+ all, you should replace references to the kernel in package names
+ with ``${KERNEL_PACKAGE_NAME}``. For example, if you disable
+ automatic installation of the kernel image using
+ ``RDEPENDS_kernel-base = ""`` you can avoid warnings using
+ ``RDEPENDS_${KERNEL_PACKAGE_NAME}-base = ""`` instead.
+
+- The ``buildhistory`` class commits changes to the repository by
+ default so you no longer need to set ``BUILDHISTORY_COMMIT = "1"``.
+ If you want to disable commits you need to set
+ ``BUILDHISTORY_COMMIT = "0"`` in your configuration.
+
+- The ``beaglebone`` reference machine has been renamed to
+ ``beaglebone-yocto``. The ``beaglebone-yocto`` BSP is a reference
+ implementation using only mainline components available in
+ OpenEmbedded-Core and ``meta-yocto-bsp``, whereas Texas Instruments
+ maintains a full-featured BSP in the ``meta-ti`` layer. This rename
+ avoids the previous name clash that existed between the two BSPs.
+
+- The ``update-alternatives`` class no longer works with SysV ``init``
+ scripts because this usage has been problematic. Also, the
+ ``sysklogd`` recipe no longer uses ``update-alternatives`` because it
+ is incompatible with other implementations.
+
+- By default, the :ref:`cmake <ref-classes-cmake>` class uses
+ ``ninja`` instead of ``make`` for building. This improves build
+ performance. If a recipe is broken with ``ninja``, then the recipe
+ can set ``OECMAKE_GENERATOR = "Unix Makefiles"`` to change back to
+ ``make``.
+
+- The previously deprecated ``base_*`` functions have been removed in
+ favor of their replacements in ``meta/lib/oe`` and
+ ``bitbake/lib/bb``. These are typically used from recipes and
+ classes. Any references to the old functions must be updated. The
+ following table shows the removed functions and their replacements:
+
+ +------------------------------+----------------------------------------------------------+
+ | *Removed* | *Replacement* |
+ +==============================+==========================================================+
+ | base_path_join() | oe.path.join() |
+ +------------------------------+----------------------------------------------------------+
+ | base_path_relative() | oe.path.relative() |
+ +------------------------------+----------------------------------------------------------+
+ | base_path_out() | oe.path.format_display() |
+ +------------------------------+----------------------------------------------------------+
+ | base_read_file() | oe.utils.read_file() |
+ +------------------------------+----------------------------------------------------------+
+ | base_ifelse() | oe.utils.ifelse() |
+ +------------------------------+----------------------------------------------------------+
+ | base_conditional() | oe.utils.conditional() |
+ +------------------------------+----------------------------------------------------------+
+ | base_less_or_equal() | oe.utils.less_or_equal() |
+ +------------------------------+----------------------------------------------------------+
+ | base_version_less_or_equal() | oe.utils.version_less_or_equal() |
+ +------------------------------+----------------------------------------------------------+
+ | base_contains() | bb.utils.contains() |
+ +------------------------------+----------------------------------------------------------+
+ | base_both_contain() | oe.utils.both_contain() |
+ +------------------------------+----------------------------------------------------------+
+ | base_prune_suffix() | oe.utils.prune_suffix() |
+ +------------------------------+----------------------------------------------------------+
+ | oe_filter() | oe.utils.str_filter() |
+ +------------------------------+----------------------------------------------------------+
+ | oe_filter_out() | oe.utils.str_filter_out() (or use the \_remove operator) |
+ +------------------------------+----------------------------------------------------------+
+
+- Using ``exit 1`` to explicitly defer a postinstall script until first
+ boot is now deprecated since it is not an obvious mechanism and can
+ mask actual errors. If you want to explicitly defer a postinstall to
+ first boot on the target rather than at ``rootfs`` creation time, use
+ ``pkg_postinst_ontarget()`` or call
+ ``postinst_intercept delay_to_first_boot`` from ``pkg_postinst()``.
+ Any failure of a ``pkg_postinst()`` script (including ``exit 1``)
+ will trigger a warning during ``do_rootfs``.
+
+ For more information, see the
+ ":ref:`dev-manual/common-tasks:post-installation scripts`"
+ section in the Yocto Project Development Tasks Manual.
+
+- The ``elf`` image type has been removed. This image type was removed
+ because the ``mkelfimage`` tool that was required to create it is no
+ longer provided by coreboot upstream and required updating every time
+ ``binutils`` updated.
+
+- Support for .iso image compression (previously enabled through
+ ``COMPRESSISO = "1"``) has been removed. The userspace tools
+ (``zisofs-tools``) are unmaintained and ``squashfs`` provides better
+ performance and compression. In order to build a live image with
+ squashfs+lz4 compression enabled you should now set
+ ``LIVE_ROOTFS_TYPE = "squashfs-lz4"`` and ensure that ``live`` is in
+ ``IMAGE_FSTYPES``.
+
+- Recipes with an unconditional dependency on ``libpam`` are only
+ buildable with ``pam`` in :term:`DISTRO_FEATURES`. If the dependency is
+ truly optional then it is recommended that the dependency be
+ conditional upon ``pam`` being in ``DISTRO_FEATURES``.
+
+- For EFI-based machines, the bootloader (``grub-efi`` by default) is
+ installed into the image at /boot. Wic can be used to split the
+ bootloader into separate boot and rootfs partitions if necessary.
+
+- Patches whose context does not match exactly (i.e. where patch
+ reports "fuzz" when applying) will generate a warning. For an example
+ of this see :yocto_git:`this commit
+ </poky/commit/?id=cc97bc08125b63821ce3f616771830f77c456f57>`.
+
+- Layers are expected to set ``LAYERSERIES_COMPAT_layername`` to match
+ the version(s) of OpenEmbedded-Core they are compatible with. This is
+ specified as codenames using spaces to separate multiple values (e.g.
+ "rocko sumo"). If a layer does not set
+ ``LAYERSERIES_COMPAT_layername``, a warning will is shown. If a layer
+ sets a value that does not include the current version ("sumo" for
+ the 2.5 release), then an error will be produced.
+
+- The ``TZ`` environment variable is set to "UTC" within the build
+ environment in order to fix reproducibility problems in some recipes.
+
+