On Tue, Jun 13, 2006 at 09:24:34PM +0200, Michael Schierl wrote: > [please cc: me since I am not subscribed on the list] > > Hi, > > First, If this is the wrong list to discuss kexec, please tell me. It is > hard to find any homepage or documentation about kexec in the web. > > I am trying to use kexec to run some X86 real-mode code from Linux. I > tried to mimic a bzImage file, but although GRUB and ISOLINUX load it, > kexec (the userland program from kexec-tools) does not like to load the > image at all (I used the --real-mode switch but it did not help). > > [My aim is to to chainload another (non-free) OS by loading its boot > sector into memory and executing it. Just like chainloader in GRUB, but > from kexec.] > > Now I created a "hello world kernel" that just echoes "Hello world" > using Int 0x10 BIOS function. That one shows the same behaviour. Works > in GRUB, but not with kexec. > > I uploaded this "kernel" to > http://home.arcor.de/mschierlm/test/hello.tar.gz > if anyone wants to have a look at it. > > Is it just impossible to load real mode code with kexec? Or is another > kernel format than bzImage more appropriate? Where do I find > documentation for those other formats (if they may work better?)
Taking a wild stab in the tark, I suspect that your problem is that when a kernel is run by kexec it skips all the BIOS stuff. I have to confess that I really don't know what the is Int 0x10 BIOS function, but it sounds problemeatic in a kexec context to me. Other than that, I think that yes you should be able to use kexec to bootstrap into any kind of kernel (or code running in real mode). Certainly linux->xen is possible (and with patches I have posted to xen-devel, xen->xen and xen->linux, though thats not really relevant), so its not restricted to booting linux. -- Horms http://www.vergenet.net/~horms/ _______________________________________________ fastboot mailing list [email protected] https://lists.osdl.org/mailman/listinfo/fastboot
