84bf4efc11
In ISO live, if the size of efi.img > 32MB, and copy EFI application
(bootx64.efi) to efi.img behind of kernel and initrd, UEFI system
could not find EFI application bootx64.efi
Using QEMU+OVMF to boot ISO live image, press ESC to enter UEFI shell:
...
Shell> ls FS0:\
Directory of: FS0:\
04/05/2011 23:00 12,985,344 bzImage
04/05/2011 23:00 <DIR> 2,048 EFI
04/05/2011 23:00 20,494,696 initrd
04/05/2011 23:00 26 startup.nsh
3 File(s) 33,480,066 bytes
1 Dir(s)
Shell> ls FS0:\EFI
Directory of: FS0:\EFI
0 File(s) 0 bytes
0 Dir(s)
...
In following case, add 64MB extra space to bootable image efi.img,
and the partition table of EFI is truncated to 26.3M
$ echo 'IMAGE_FSTYPES:pn-core-image-minimal = " live"' >> conf/local.conf
$ echo 'MACHINE_FEATURES:append = " efi pcbios"' >> conf/local.conf
$ echo '# 64MB extra space to bootable image efi.img' >> conf/local.conf
$ echo 'BOOTIMG_EXTRA_SPACE = "65535"' >> conf/local.conf
$ bitbake core-image-minimal
$ fdisk -l tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.rootfs.iso
...
Device Boot Start End Sectors Size Id Type
tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.rootfs.iso1 * 0 376831 376832 184M 0 Empty
tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.rootfs.iso2 120 54079 53960 26.3M ef EFI (FAT-12/16/32)
According to page 11: `Figure 5 - Section Entry' in El Torito Bootable
CD-ROM Format Specification [1]. The sector count takes 2 byte which
means max sector count is 0xffff (65535), for 512-byte sector, the
size of bootable image is no more than 32MB (65536 * 512 / 1024 / 1024)
This commit truncate to 32MB if image size larger than 32MB, and
report a warning, then save the extra image sector count to
vendor unique selection criteria
After apply this commit, the partition table of EFI is truncated to 32M
$ fdisk -l tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.rootfs.iso
...
Device Boot Start End Sectors Size Id Type
tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.rootfs.iso1 * 0 376831 376832 184M 0 Empty
tmp/deploy/images/qemux86-64/core-image-minimal-qemux86-64.rootfs.iso2 120 65654 65535 32M ef EFI (FAT-12/16/32)
[1]https://pdos.csail.mit.edu/6.828/2017/readings/boot-cdrom.pdf
(From OE-Core rev: 259bb8907d8bfe1217e88a3b6935c160e5a92f8d)
(From OE-Core rev: d184f119c26983c2f15b47a25204049d0525c871)
Signed-off-by: Hongxu Jia <hongxu.jia@windriver.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Steve Sakoman <steve@sakoman.com>
Poky
Poky is an integration of various components to form a pre-packaged build system and development environment which is used as a development and validation tool by the Yocto Project. It features support for building customised embedded style device images and custom containers. There are reference demo images ranging from X11/GTK+ to Weston, commandline and more. The system supports cross-architecture application development using QEMU emulation and a standalone toolchain and SDK suitable for IDE integration.
Additional information on the specifics of hardware that Poky supports is available in README.hardware. Further hardware support can easily be added in the form of BSP layers which extend the systems capabilities in a modular way. Many layers are available and can be found through the layer index.
As an integration layer Poky consists of several upstream projects such as BitBake, OpenEmbedded-Core, Yocto documentation, the 'meta-yocto' layer which has configuration and hardware support components. These components are all part of the Yocto Project and OpenEmbedded ecosystems.
The Yocto Project has extensive documentation about the system including a reference manual which can be found at https://docs.yoctoproject.org/
OpenEmbedded is the build architecture used by Poky and the Yocto project. For information about OpenEmbedded, see the OpenEmbedded website.
Contribution Guidelines
Please refer to our contributor guide here: https://docs.yoctoproject.org/dev/contributor-guide/ for full details on how to submit changes.
Where to Send Patches
As Poky is an integration repository (built using a tool called combo-layer), patches against the various components should be sent to their respective upstreams:
OpenEmbedded-Core (files in meta/, meta-selftest/, meta-skeleton/, scripts/):
- Git repository: https://git.openembedded.org/openembedded-core/
- Mailing list: openembedded-core@lists.openembedded.org
BitBake (files in bitbake/):
- Git repository: https://git.openembedded.org/bitbake/
- Mailing list: bitbake-devel@lists.openembedded.org
Documentation (files in documentation/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/yocto-docs/
- Mailing list: docs@lists.yoctoproject.org
meta-yocto (files in meta-poky/, meta-yocto-bsp/):
- Git repository: https://git.yoctoproject.org/cgit/cgit.cgi/meta-yocto
- Mailing list: poky@lists.yoctoproject.org
If in doubt, check the openembedded-core git repository for the content you intend to modify as most files are from there unless clearly one of the above categories. Before sending, be sure the patches apply cleanly to the current git repository branch in question.