This is a note to let you know that I've just added the patch titled perf debug: Set debug_peo_args and redirect_to_stderr variable to correct values in perf_quiet_option() to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: perf-debug-set-debug_peo_args-and-redirect_to_stderr.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 89c993022aa6a6726562fff7cb6f6bb78acd2520 Author: Yang Jihong <yangjihong1@xxxxxxxxxx> Date: Tue Dec 20 11:57:00 2022 +0800 perf debug: Set debug_peo_args and redirect_to_stderr variable to correct values in perf_quiet_option() [ Upstream commit 188ac720d364035008a54d249cf47b4cc100f819 ] When perf uses quiet mode, perf_quiet_option() sets the 'debug_peo_args' variable to -1, and display_attr() incorrectly determines the value of 'debug_peo_args'. As a result, unexpected information is displayed. Before: # perf record --quiet -- ls > /dev/null ------------------------------------------------------------ perf_event_attr: size 128 { sample_period, sample_freq } 4000 sample_type IP|TID|TIME|PERIOD read_format ID|LOST disabled 1 inherit 1 mmap 1 comm 1 freq 1 enable_on_exec 1 task 1 precise_ip 3 sample_id_all 1 exclude_guest 1 mmap2 1 comm_exec 1 ksymbol 1 bpf_event 1 ------------------------------------------------------------ ... After: # perf record --quiet -- ls > /dev/null # redirect_to_stderr is a similar problem. Fixes: f78eaef0e0493f60 ("perf tools: Allow to force redirect pr_debug to stderr.") Fixes: ccd26741f5e6bdf2 ("perf tool: Provide an option to print perf_event_open args and return value") Suggested-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> Reviewed-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> Signed-off-by: Yang Jihong <yangjihong1@xxxxxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Carsten Haitzler <carsten.haitzler@xxxxxxx> Cc: Ian Rogers <irogers@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Leo Yan <leo.yan@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: martin.lau@xxxxxxxxxx Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Ravi Bangoria <ravi.bangoria@xxxxxxx> Cc: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20221220035702.188413-2-yangjihong1@xxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/tools/perf/util/debug.c b/tools/perf/util/debug.c index 682146d04379..112cb85f6086 100644 --- a/tools/perf/util/debug.c +++ b/tools/perf/util/debug.c @@ -232,6 +232,10 @@ int perf_quiet_option(void) var++; } + /* For debug variables that are used as bool types, set to 0. */ + redirect_to_stderr = 0; + debug_peo_args = 0; + return 0; }