From: Tvrtko Ursulin <[email protected]> To allow system administrators finer-grained control over security settings, we add an optional pmu->is_privileged(pmu, event) callback which is consulted when unprivileged system-wide uncore event collection is disabled.
Signed-off-by: Tvrtko Ursulin <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: [email protected] Cc: Dmitry Rogozhkin <[email protected]> Cc: Chris Wilson <[email protected]> --- include/linux/perf_event.h | 6 ++++++ kernel/events/core.c | 12 +++++++++++- 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 8e22f24ded6a..a93630cad6b9 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -446,6 +446,12 @@ struct pmu { * Filter events for PMU-specific reasons. */ int (*filter_match) (struct perf_event *event); /* optional */ + + /* + * Returns true if the event needs CAP_SYS_ADMIN privilege in system- + * wide mode. + */ + bool (*is_privileged) (struct perf_event *event); /* optional */ }; /** diff --git a/kernel/events/core.c b/kernel/events/core.c index 1811dd5aa2e2..adec28c879e8 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3847,6 +3847,16 @@ find_lively_task_by_vpid(pid_t vpid) return task; } +static bool cpu_is_privileged(struct pmu *pmu, struct perf_event *event) +{ + bool privileged = perf_paranoid_cpu(); + + if (privileged && pmu->is_privileged) + privileged = pmu->is_privileged(event); + + return privileged; +} + /* * Returns a matching context with refcount and pincount. */ @@ -3863,7 +3873,7 @@ find_get_context(struct pmu *pmu, struct task_struct *task, if (!task) { /* Must be root to operate on a CPU event: */ - if (perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN)) + if (cpu_is_privileged(pmu, event) && !capable(CAP_SYS_ADMIN)) return ERR_PTR(-EACCES); cpuctx = per_cpu_ptr(pmu->pmu_cpu_context, cpu); -- 2.14.1 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
