Commit 4b0297ef authored Aug 05, 2020 by Alexey Budankov Committed by Arnaldo Carvalho de Melo Aug 06, 2020

perf evsel: Extend message to mention CAP_SYS_PTRACE and perf security doc link

Adjust limited access message to mention CAP_SYS_PTRACE capability for
processes of unprivileged users. Add link to perf security document in
the end of the section about capabilities.

The change has been inspired by this discussion:
https://lore.kernel.org/lkml/20200722113007.GI77866@kernel.org/



Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/6f8a7425-6e7d-19aa-1605-e59836b9e2a6@linux.intel.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

parent 347a7389

tools/perf/util/evsel.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -2502,8 +2502,10 @@ int evsel__open_strerror(struct evsel evsel, struct target target,

		return scnprintf(msg + printed, size - printed,
		"Consider adjusting /proc/sys/kernel/perf_event_paranoid setting to open\n"
		"access to performance monitoring and observability operations for users\n"
		"without CAP_PERFMON or CAP_SYS_ADMIN Linux capability.\n"
		"access to performance monitoring and observability operations for processes\n"
		"without CAP_PERFMON, CAP_SYS_PTRACE or CAP_SYS_ADMIN Linux capability.\n"
		"More information can be found at 'Perf events and tool security' document:\n"
		"https://www.kernel.org/doc/html/latest/admin-guide/perf-security.html\n"
		"perf_event_paranoid setting is %d:\n"
		" -1: Allow use of (almost) all events by all users\n"
		" Ignore mlock limit after perf_event_mlock_kb without CAP_IPC_LOCK\n"

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