On 2012-09-19 16:38, Avi Kivity wrote: > On 09/17/2012 10:36 PM, Dean Pucsek wrote: >> Hello, >> >> For my Masters thesis I am investigating the usage of Intel VT-x and branch >> tracing in the domain of malware analysis. Essentially what I'm aiming to >> do is trace the execution of a guest VM and then pass that trace on to some >> other tools. I've been playing KVM for a couple weeks now but from comments >> such as (in arch/x86/kvm/vmx.c): >> >> /* >> * Forward all other exceptions that are valid in real mode. >> * FIXME: Breaks guest debugging in real mode, needs to be fixed with >> * the required debugging infrastructure rework. >> */ >> >> And (from an email sent to the list in July 2008): >> >> Note that guest debugging in real mode is broken now. This has to be >> fixed by the scheduled debugging infrastructure rework (will be done >> once base patches for QEMU have been accepted). >> >> it is unclear to me how much support there is for guest debugging in KVM >> currently (I wasn't able to find any recent documentation on it) and what >> the debugging infrastructure referred to by these comments is. I am >> interested in becoming involved with the KVM project in this respect however >> some guidance and direction on the guest debugging facilities would be >> greatly appreciated. > > Guest debugging works (but not in real mode due to the issue above).
That doesn't apply to CPUs with "Unrestricted Guest" support, right? At least I didn't notice any limitations recently. [I did notice some other corner-case issue with guest debugging, still need to dig into that...] > You can set hardware and software breakpoints and kvm will forward them > to userspace, and from there to the debugger. I'll be happy to help, as > I'm sure Jan (as the author of most of the guest debugging code) will as > well. > This may help as a starter: http://chemnitzer.linux-tage.de/2012/vortraege/folien/1061-VirtualDebugging.pdf Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
