The second OS for the fresh sun4v emulation under QEMU

... is HelenOS. Although I was not able to boot the official 0.4 and 0.6.0 releases due to known problems with SILO (or OBP/Hypervisor), the current version works just fine:

HelenOS 0.6.0 revision 2521 under QEMU/sun4v

Note the nice reddish prompt. No other OS bootable under sun4v QEMU sparc64 emulation has something similar out of the box!

More math bugs

 Why would one file system work, and another one - not?

Because the fs driver is buggy? Of course not! The ones who read this blog on a regular basis, know that inability to read the file has to do with a bug in a math emulation.

Thanks to Jakub's test case, I fixed two bugs with carry flag handling (yes, again). Now HelenOS/sparc64 boot looks like this:

My impressions of HelenOS - it's neat, the sources are good documented and easy readable. Also I needed just a few minutes to set up cross compiling under Linux/x86_64. So, if you need a small, micro-kernel(!) and multi-arch (amd64, arm32, ia32, ia64, mips32, ppc32, sparc64) OS to play with, HelenOS is definitely worth looking at.