Re: perf: rdpmc bug when viewing all procs on remote cpu

Vince Weaver
2019-01-10T20:00:18Z

On Thu, 10 Jan 2019, Vince Weaver wrote:

> On Thu, 10 Jan 2019, Vince Weaver wrote:
>
> > However if you create an all-process attached to CPU event:
> > perf_event_open(attr, -1, X, -1, 0);
> > the mmap event index is set as if this were a valid event and so the rdpmc
> > succeeds even though it shouldn't (we're trying to read an event value
> > on a remote cpu with a local rdpmc).
>
> For a test case, try the
> tests/rdpmc/rdpmc_attach_other_cpu
> test found in my perf_event_tests suite
> git clone https://github.com/deater/perf_event_tests

and that was a cut-and-paste error, I meant
tests/rdpmc/rdpmc_attach_global_cpu
and I was wrong, it does affect AMD machines too.

Vince