Re: [Xen-devel] Last Branch Record (LBR) in Xen

["Jan Beulich" <JBeulich@xxxxxxxxxx>]

>>> Abhinav Srivastava <abhinavs_iitkgp@xxxxxxxxxxx> 26.06.09 15:50 >>>
>As far as I understand (please correct me if I am wrong), you meant that HVM 
>guests have to enable the LBR recording, and
>this action cannot be initiated/controlled by Xen. I was thinking like other 
>kind of actions, such as single stepping on instruction,
>single stepping on branch etc. that can be controlled from the hypervisor and 
>guests behave accordingly, the LBR feature can
>also be set/reset from the hypervisor. And, if that is not the case then I 
>think any malicious programs can turn off this feature
>inside HVM guests and can bypass the debugger. Moreover, I assumed anything 
>that a guest can do, can also be done from
>the hypervisor by setting guest MSR registers or bitmap from the hypervisor.

Oh, of course this can be done from the hypervisor, but that wasn't the purpose 
of the patch. You'd have to code this for yourself.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel