Re: [PATCH v4 2/9] perf/core: open access for CAP_SYS_PERFMON privileged process

Arnaldo Carvalho de Melo <[email protected]> Fri, 10 Jan 2020 13:45:31 -0300

Newsgroups	gmane.linux.ports.arm.kernel,gmane.linux.oprofile,gmane.comp.freedesktop.xorg.drivers.intel,gmane.linux.ports.parisc,gmane.linux.kernel,gmane.linux.kernel.perf.user,gmane.linux.kernel.lsm,gmane.linux.ports.ppc64.devel
Message-ID	<[email protected]>

Em Sat, Jan 11, 2020 at 12:52:13AM +0900, Masami Hiramatsu escreveu:
> On Fri, 10 Jan 2020 15:02:34 +0100 Peter Zijlstra <[email protected]> wrote:
> > Again, this only allows attaching to previously created kprobes, it does
> > not allow creating kprobes, right?

> > That is; I don't think CAP_SYS_PERFMON should be allowed to create
> > kprobes.

> > As might be clear; I don't actually know what the user-ABI is for
> > creating kprobes.

> There are 2 ABIs nowadays, ftrace and ebpf. perf-probe uses ftrace interface to
> define new kprobe events, and those events are treated as completely same as
> tracepoint events. On the other hand, ebpf tries to define new probe event
> via perf_event interface. Above one is that interface. IOW, it creates new kprobe.

Masami, any plans to make 'perf probe' use the perf_event_open()
interface for creating kprobes/uprobes?

- Arnaldo