James Jacobsson wrote: > I've gotten a fair bit on my device emulation code. The linux kernel > is actually booting all the way to mounting the root FS right now. >
Very impressive. I keep saying how kvm isn't tied to qemu, but I never thought someone would go and actually do it. > Currently I'm working on sorting out some bugs in the ATA irq > handling, so there's definitely some progress. > Thanks for your help, Avi and Dor. I wouldn't gotten this far this > fast without your help. > > However, I'm currently "cheating" by loading 32 bit ELF binaries and > executing them, instead of doing a complete boot sequence starting > with a BIOS. This will of course stop me dead in the tracks if I > wanted to launch anything but OSS *NIX systems. > > So, my question is: > What's needed to get the x86_emulate.c code in a better state (the > TODO page says something needs to be done), and how would I go about > starting KVM in real-mode? > Will it do everything right if I just set cr0 to indicate that we're > not executing in 32bit more? > The vcpu creation ioctl() creates a vcpu just after a reset - that is, ready to run the first bios instruction. You will need to load your bios to physical address 0xf0000, but that's it. > Will KVM spit out some kind of debug information when it encounters an > instruction it cannot handle ? > > It will say 'emulation failed but !something' and the instruction opcodes. x86_emulate.c does need an overhaul. It can boot Windows and some Linuces but some boot loaders confuse it. The following needs to be done: - get rid of the dependency on cr2. I did most of this work by adding mod r/m decoding, however a bit more needs to be done for absolute address references. - add support for reg/reg instructions. For example, mov reg, mem is supported but mov reg, reg is not. - add support for more instructions - branches, stack operations, etc. I see that Xen has been doing much the same for their x86_emulate.c, so we can probably pick up some of the changes from them. -- error compiling committee.c: too many arguments to function ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
