Thanks a lot for the information. From what I see, the Atom P series are server-grade processors. Would you happen to know if any Desktop/Workstation processors (ex. 10th gen i9) also support this feature? Specifically, I'm referring to Comet Lake, here -- https://ark.intel.com/content/www/us/en/ark/products/codename/90354/comet-lake.html Aditya Aditya On Mon, Mar 1, 2021 at 8:16 PM Xu, Like <like.xu@xxxxxxxxx> wrote: > > On 2021/3/2 2:48, Aditya Basu wrote: > > Hi all, > > I am a PhD student at the Pennsylvania State University. For my > > current project, I am trying to run Intel Processor Trace (PT) inside > > a Guest VM. Specifically, I want to run KVM in the "Host-Guest mode" > > as stated in the following bug: > > https://bugzilla.kernel.org/show_bug.cgi?id=201565 > > > > However, I *cannot* find an Intel processor that supports this mode. I > > have tried using Intel's i7-7700 and i7-9700k processors. Based on my > > findings, the problem seems to be that bit 24 (PT_USE_GPA) of > > MSR_IA32_VMX_PROCBASED_CTLS2 (high) is reported as 0 by the processor. > > Hence, KVM seems to force pt_mode to 0 (or PT_MODE_HOST). > > You may try the Intel Atom® Processor P* Series. > > https://ark.intel.com/content/www/us/en/ark/products/series/29035/intel-atom-processor.html?wapkw=Atom#@Server > > > > > I would appreciate any pointers that someone might have regarding the > > above. Specifically, I want to find an Intel processor that supports > > running Intel PT in "Host-Guest mode". > > > > Regards, > > > > Aditya Basu > > PhD Student in CSE > > Pennsylvania State University > > https://www.adityabasu.me/ >
