From 1a5efc9e13f357abc396dbf445b25d08914c8060 Mon Sep 17 00:00:00 2001 From: Aditya Gupta Date: Wed, 4 Sep 2024 11:48:30 +0530 Subject: libsubcmd: Don't free the usage string Currently, commands which depend on 'parse_options_subcommand()' don't show the usage string, and instead show '(null)' $ ./perf sched Usage: (null) -D, --dump-raw-trace dump raw trace in ASCII -f, --force don't complain, do it -i, --input input file name -v, --verbose be more verbose (show symbol address, etc) 'parse_options_subcommand()' is generally expected to initialise the usage string, with information in the passed 'subcommands[]' array This behaviour was changed in: 230a7a71f92212e7 ("libsubcmd: Fix parse-options memory leak") Where the generated usage string is deallocated, and usage[0] string is reassigned as NULL. As discussed in [1], free the allocated usage string in the main function itself, and don't reset usage string to NULL in parse_options_subcommand With this change, the behaviour is restored. $ ./perf sched Usage: perf sched [] {record|latency|map|replay|script|timehist} -D, --dump-raw-trace dump raw trace in ASCII -f, --force don't complain, do it -i, --input input file name -v, --verbose be more verbose (show symbol address, etc) [1]: https://lore.kernel.org/linux-perf-users/htq5vhx6piet4nuq2mmhk7fs2bhfykv52dbppwxmo3s7du2odf@styd27tioc6e/ Fixes: 230a7a71f92212e7 ("libsubcmd: Fix parse-options memory leak") Suggested-by: Namhyung Kim Signed-off-by: Aditya Gupta Acked-by: Namhyung Kim Tested-by: Arnaldo Carvalho de Melo Cc: Athira Rajeev Cc: Disha Goel Cc: Ian Rogers Cc: Jiri Olsa Cc: Kajol Jain Cc: Madhavan Srinivasan Cc: Namhyung Kim Link: https://lore.kernel.org/r/20240904061836.55873-2-adityag@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-kvm.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'tools/perf/builtin-kvm.c') diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c index 692267b1b7e8..55ea17c5ff02 100644 --- a/tools/perf/builtin-kvm.c +++ b/tools/perf/builtin-kvm.c @@ -2184,5 +2184,8 @@ int cmd_kvm(int argc, const char **argv) else usage_with_options(kvm_usage, kvm_options); + /* free usage string allocated by parse_options_subcommand */ + free((void *)kvm_usage[0]); + return 0; } -- cgit v1.2.3