====== Daniel Verkamp: COMBOOT Support ====== ===== Journal ===== ==== Week 6 ==== ---- === 30 June 2008 === * Discussed (with hpa and mcb30) implementation of newer Run kernel image function and Get configuration filename function; learned that menu.c32 and friends take an optional command line parameter to specify the configuration filename, so for now I will avoid implementing the configuration filename function until I'm sure how to do it to ensure the best compatibility with SYSLINUX/PXELINUX. Added parsing of kernel command line to get initrd= parameter and load it, but unfinished, as I am not sure of the best way to load the initrd myself (building a command to pass to system(), exposing some of the hci functionality internally, etc.) === 01 July 2008 === * Finished initial implementation of "Run kernel image" function; testing it with the standard gtest.gpxe/tomsrtbt images, it fails in the middle of loading the bzimage (qemu reports a jump outside of memory); worked on trying to debug this for a while, but DEBUG=bzimage didn't print any messages, so it seems to be before the bzimage image type even gets involved. More debugging tomorrow, and maybe the GDB stub will help... === 02 July 2008 === * Still more debugging; no real progress yet in determining the problem with menu bzimage loading. === 03 July 2008 === * Seems to be dying during the HTTP download, judging by DEBUG=http. Tracing deeper... === 04 July 2008 === * Thanks to invaluable help from Stefan, we've determined that the problem is due to the memory used for the com32 stack not being marked as used and therefore being overwritten; Stefan noted that he was working on a umalloc patch to allow multiple heaps, which could help solve this problem. Also noticed that com32 wasn't calling image_unregister like comboot; adding this, menu.c32 does work correctly on a real hardware test machine (probably by luck, noting the memory overwrites mentioned above) to boot tomsrtbt and a 16-bit COMBOOT program. However, it does not correctly boot another instance of menu.c32; more investigation to follow once the memory allocation issue is solved.