Arnaldo Carvalho de Melo <a...@kernel.org> writes: > Em Tue, Feb 14, 2017 at 03:24:16PM +0200, Alexander Shishkin escreveu: >> On systems where PT does not coexist with VMX, users get confused when >> PT turns up with no data because they forgot they're running a kvm >> session at the same time. >> >> This patch adds a preemptive check for any active VMX operations that >> will fail event creation. This does not provide any guarantees or >> protection against racing with a kvm starting in parallel, but is >> intended to serve as a hint for the user. If VMXON happens after an >> event had been created, the event will still produce an empty trace. >> >> Signed-off-by: Alexander Shishkin <alexander.shish...@linux.intel.com> >> Reported-by: Andi Kleen <a...@linux.intel.com> > > Yeah, I saw that as well, and Andi told me about this limitation, so, > for quite a while now, everytime I need to test PT on the only machine I > have with it, I have to stop my kvm sessions :-\ > > Thanks for working on this!
Well, we can't make the limitation go away. You'll still have to stop kvms to get any 'meaningful' PT data. Regards, -- Alex
