> > In this circumstances CAP_SYS_PERFMON looks like smart balanced advancement that > > trade-offs between perf_events subsystem extensions, required level of control > > and configurability of perf_events, existing users adoption effort, and it brings > > security hardening benefits of decreasing attack surface for the existing users > > and use cases. > > I'm not 100% opposed to CAP_SYS_PERFMON. I am 100% opposed to new capabilities > that have a single use. Surely there are other CAP_SYS_ADMIN users that [cs]ould > be converted to CAP_SYS_PERFMON as well. If there is a class of system performance > privileged operations, say a dozen or so, you may have a viable argument. perf events is not a single use. It has a bazillion of sub functionalities, including hardware tracing, software tracing, pmu counters, software counters, uncore counters, break points and various other stuff in its PMU drivers. See it more as a whole quite heterogenous driver subsystem. I guess CAP_SYS_PERFMON is not a good name because perf is much more than just Perfmon. Perhaps call it CAP_SYS_PERF_EVENTS -Andi
