It is not easy to cause a VMEXIT on execution of SYSCALL. The reads of the
SYSCALL MSRs which the processor must internally execute as part of this
instruction are not interceptable like normal RDMSR instructions.
-- Keir
On 3/9/08 19:29, "Emre Can Sezer" <ecsezer@ncsu.edu> wrote:
> Hi, I''ve set up a 64-bit HVM guest and was wondering if there is
anyway I
> can determine when the privilege level escalates to 0. My goal is to
> determine when execution jumps to the guest kernel. This includes
> external interrupts as well as internal ones like system calls.
>
> I''ve read through the source code especially vmx.c, vmcs.c and
exit.S as
> well as the intel documentation on vmx, yet I couldn''t figure out
if I can
> set the bitmap so that system calls cause a VMEXIT.
>
> Is there a way I can capture whenever execution jumps into kernel?
I''ve
> enabled MSR read/writes to cause VMEXIT''s but even then I
don''t see a read
> from VMX_SYSENTER_CS/EIP/ESP. I don''t know if setting the
MSR_GS_BASE or
> MSR_FS_BASE is any indication.
>
> I''m thinking about setting the debug registers in the VM so that
the
> system call entry points trap into the VMM.
>
> I appreciate any help or advice on the matter.
>
> Thanks in advance,
>
> John
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xensource.com
http://lists.xensource.com/xen-devel