From: Konstantin Khlebnikov <[email protected]> Fix misprint CAP_IOC_LOCK -> CAP_IPC_LOCK. This capability have nothing to do with raw tracepoints. This part is about bypassing mlock limits.
Sysctl kernel.perf_event_paranoid = -1 allows raw and ftrace function tracepoints without CAP_SYS_ADMIN. Signed-off-by: Konstantin Khlebnikov <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Peter Zijlstra <[email protected]> Link: http://lkml.kernel.org/r/150322916080.129746.11285255474738558340.stgit@buzz Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> --- Documentation/sysctl/kernel.txt | 13 ++++++++++++- tools/perf/util/evsel.c | 4 +++- 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index bac23c198360..ce61d1fe08ca 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -61,6 +61,7 @@ show up in /proc/sys/kernel: - perf_cpu_time_max_percent - perf_event_paranoid - perf_event_max_stack +- perf_event_mlock_kb - perf_event_max_contexts_per_stack - pid_max - powersave-nap [ PPC only ] @@ -654,7 +655,9 @@ Controls use of the performance events system by unprivileged users (without CAP_SYS_ADMIN). The default value is 2. -1: Allow use of (almost) all events by all users ->=0: Disallow raw tracepoint access by users without CAP_IOC_LOCK + Ignore mlock limit after perf_event_mlock_kb without CAP_IPC_LOCK +>=0: Disallow ftrace function tracepoint by users without CAP_SYS_ADMIN + Disallow raw tracepoint access by users without CAP_SYS_ADMIN >=1: Disallow CPU event access by users without CAP_SYS_ADMIN >=2: Disallow kernel profiling by users without CAP_SYS_ADMIN @@ -673,6 +676,14 @@ The default value is 127. ============================================================== +perf_event_mlock_kb: + +Control size of per-cpu ring buffer not counted agains mlock limit. + +The default value is 512 + 1 page + +============================================================== + perf_event_max_contexts_per_stack: Controls maximum number of stack frame context entries for diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 5dfb8bc4db89..a5888c704e01 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -2674,7 +2674,9 @@ int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target, "unprivileged users (without CAP_SYS_ADMIN).\n\n" "The current value is %d:\n\n" " -1: Allow use of (almost) all events by all users\n" - ">= 0: Disallow raw tracepoint access by users without CAP_IOC_LOCK\n" + " Ignore mlock limit after perf_event_mlock_kb without CAP_IPC_LOCK\n" + ">= 0: Disallow ftrace function tracepoint by users without CAP_SYS_ADMIN\n" + " Disallow raw tracepoint access by users without CAP_SYS_ADMIN\n" ">= 1: Disallow CPU event access by users without CAP_SYS_ADMIN\n" ">= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN\n\n" "To make this setting permanent, edit /etc/sysctl.conf too, e.g.:\n\n" -- 2.13.5
