CELF Project Proposal/Improve kexecboot - Revision history

Jay7: /* Comments */ remove link to lost page

2011-04-19T21:46:39Z

‎Comments: remove link to lost page

Jay7: /* Comments */ Add status section

2011-04-19T21:45:57Z

‎Comments: Add status section

Jay7: /* Proposed improvements */ add final status

2011-04-19T21:44:20Z

‎Proposed improvements: add final status

Jay7: /* Links */ add link to kexecboot.org site

2011-04-19T21:42:35Z

‎Links: add link to kexecboot.org site

Jay7: /* Related works */ qi bootmenu url changed

2011-04-19T21:41:38Z

‎Related works: qi bootmenu url changed

Tim Bird: /* Related works */

2009-12-17T22:49:12Z

‎Related works

Tim Bird: /* Developers */

2009-12-17T22:48:46Z

‎Developers

Tim Bird: add project proposal

2009-12-17T22:48:20Z

add project proposal

New page

; Summary : Improve kexecboot

; Proposer : Yuri Bushmelev

== Description ==
Kexecboot is a C program able to scan the partitions on available devices,
offering a graphical framebuffer menu and allowing user to select from which
one to boot. Specifically, kexecboot creates the command line for kexec.

Typically kexecboot resides together with kexec in a small initramfs,
embedded in a custom-tailored kernel compiled with support for initramfs and
kexec system call.
Both binaries are built static, linked against klibc to optimize size.

Flashed on NAND and launched as first kernel by the original bootloader,
this solution gives following advantages:

* multi machine support: we build for many architectures using OpenEmbedded (tested on arm and x86/x86_64)
* zImage and uImage (for arm and sh) support
* easy customization: just add machine-specific workarounds (see Zaurus raw read of bootparams from NAND)
* small size: complete linux-kexecboot_2.6.x image (initramfs + kernel) is about 1Mb (less with lzma patches)
* easy boot choice: boot from SD/CF/NAND/... even if bootloader doesn't support it
* multiple fs detection: we support many filesystems e.g. ext2/3/4, jffs2, reiserfs, vfat and more (ubifs is work in progress)
* kernel upgrade: no need to flash the device (kernel is in /boot of removable media)
* rapid testing: different distributions can live in separate partitions on the same device

Thus, kexecboot is an interesting solution for embedded linux distributions,
which can just rely on kexecboot whithout having to consider what the real
bootloader can and cannot do.

About customization, initially the program has been developed for Sharp
Zaurus PDA (armv5te).
For the machines of that family there is specific code reading bootparams
directly from NAND, circumventing the obsolete bootloader which is
incompatible with modern 2.6.x kernels.

=== Proposed improvements ===
# Write user's and developer's guides.
# Extend architecture and filesystems support.
# Improve debugging ability. We should allow users to have ability to look for debugging information without special hardware (serial cable e.g.).
# Implement text-mode UI. We have already patches against one of old releases. This can be used later to use kexecboot UI over serial line or telnet/ssh connection.
# Improve GUI. Make GUI more clean and eye-candy (fonts and icons).
# Add ability to use multiple kernels on same partition. Current implementation allow to use only one kernel per partition.

== Developers ==
* Yuri Bushmelev (jay7) - lead developer
* Thomas Kunze (thesing) - author of first proof-of-concept, initial klibc
porting
* Andrea Adami (ant) - initial Zaurus mtdparts reading, kexecboot tester and
OpenEmbedded recipe maintainer
* Eric Weiss (pwgen) - initial evdev-based event processing, touchscreen
support and OpenMoko port
* Cortez (Omegamoon) - initial config file parser, text UI patch and zUbuntu
port
* Michael Casadevall (NCommander) - new configure options, kexecboot tester
on x86

== Links ==
* project http://projects.linuxtogo.org/projects/kexecboot
* git tree http://git.linuxtogo.org/?p=groups/kexecboot/kexecboot.git
* OpenEmbedded recipes: http://www.openembedded.org

== Related works ==
* kexec-tools http://www.kernel.org/pub/linux/kernel/people/horms/kexec-
tools/README.html
* kexec-loader http://www.solemnwarning.net/kexec-loader
* Qi Bootmenu http://n2.nabble.com/RFC-Qi-Bootmenu-tp3790792ef1958.html
* Ubuntu ARMSoftbootLoader specs
http://wiki.ubuntu.com/Specs/ARMSoftbootLoader

== Scope ==
This should take about 65 hours of work.

== Comments ==
See http://projects.linuxtogo.org/mediawiki/index.php/Kexecboot:CELF

[[Category:Project proposals]]

@@ Line 59: / Line 59: @@
 * kexec-tools - http://www.kernel.org/pub/linux/kernel/people/horms/kexec-tools/README.html
 * kexec-loader - http://www.solemnwarning.net/kexec-loader
-* Qi Bootmenu - http://n2.nabble.com/RFC-Qi-Bootmenu-tp3790792ef1958.html
+* Qi Bootmenu - http://www.brain-dump.org/projects/qi-bootmenu/
 * Ubuntu ARMSoftbootLoader specs - http://wiki.ubuntu.com/Specs/ARMSoftbootLoader

@@ Line 65: / Line 65: @@
 == Scope ==
 This should take about 65 hours of work.
 == Status ==

@@ Line 68: / Line 68: @@
 == Comments ==
 See http://projects.linuxtogo.org/mediawiki/index.php/Kexecboot:CELF
 [[Category:Project proposals]]

@@ Line 36: / Line 36: @@
 === Proposed improvements ===
-# Write user's and developer's guides.
+# Write user's and developer's guides. '''Done'''
-# Extend architecture and filesystems support.
+# Extend architecture and filesystems support. '''Kexecboot was tested on MIPS (Ben NanoNote). UBIFS support was not done.'''
-# Improve debugging ability. We should allow users to have ability to look for debugging information without special hardware (serial cable e.g.).
+# Improve debugging ability. We should allow users to have ability to look for debugging information without special hardware (serial cable e.g.). '''Done'''
-# Implement text-mode UI. We have already patches against one of old releases. This can be used later to use kexecboot UI over serial line or telnet/ssh connection.
+# Implement text-mode UI. We have already patches against one of old releases. This can be used later to use kexecboot UI over serial line or telnet/ssh connection. '''Done'''
-# Improve GUI. Make GUI more clean and eye-candy (fonts and icons).
+# Improve GUI. Make GUI more clean and eye-candy (fonts and icons). '''Done'''
-# Add ability to use multiple kernels on same partition. Current implementation allow to use only one kernel per partition.
+# Add ability to use multiple kernels on same partition. Current implementation allow to use only one kernel per partition. '''Done'''
 == Developers ==

@@ Line 52: / Line 52: @@
 == Links ==
 * project http://projects.linuxtogo.org/projects/kexecboot
 * git tree http://git.linuxtogo.org/?p=groups/kexecboot/kexecboot.git

@@ Line 45: / Line 45: @@
 == Developers ==
 * Yuri Bushmelev (jay7) - lead developer
-* Thomas Kunze (thesing) - author of first proof-of-concept, initial klibc
+* Thomas Kunze (thesing) - author of first proof-of-concept, initial klibc porting
-porting
+* Andrea Adami (ant) - initial Zaurus mtdparts reading, kexecboot tester and OpenEmbedded recipe maintainer
-* Andrea Adami (ant) - initial Zaurus mtdparts reading, kexecboot tester and
+* Eric Weiss (pwgen) - initial evdev-based event processing, touchscreen support and OpenMoko port
-OpenEmbedded recipe maintainer
+* Cortez (Omegamoon) - initial config file parser, text UI patch and zUbuntu port
-* Eric Weiss (pwgen) - initial evdev-based event processing, touchscreen
+* Michael Casadevall (NCommander) - new configure options, kexecboot tester on x86
 support and OpenMoko port
 * Cortez (Omegamoon) - initial config file parser, text UI patch and zUbuntu
 port
 * Michael Casadevall (NCommander) - new configure options, kexecboot tester
 on x86
 == Links ==