On Wed, Nov 06, 2024 at 11:03:10AM -0500, Liang, Kan wrote:
> > +static unsigned long common_misc_flags(struct pt_regs *regs)
> > +{
> > + if (regs->flags & PERF_EFLAGS_EXACT)
> > + return PERF_RECORD_MISC_EXACT_IP;
> > +
> > + return 0;
> > +}
> > +
> > +unsigned long perf_arch_guest_misc_flags(struct pt_regs *regs)
> > +{
> > + unsigned long guest_state = perf_guest_state();
> > + unsigned long flags = common_misc_flags(regs);
> > +
> > + if (guest_state & PERF_GUEST_USER)
> > + flags |= PERF_RECORD_MISC_GUEST_USER;
> > + else if (guest_state & PERF_GUEST_ACTIVE)
> > + flags |= PERF_RECORD_MISC_GUEST_KERNEL;
> > +
>
> The logic of setting the GUEST_KERNEL flag is implicitly changed here.
>
> For the current code, the GUEST_KERNEL flag is set for !PERF_GUEST_USER,
> which include both guest_in_kernel and guest_in_NMI.
Where is the "guest_in_NMI" state coming from? KVM only reports user v.
kernel mode.
--
Thanks
Oliver
