This is the backport for 4.19. -- Steve ------------------ original commit in Linus's tree ------------------ >From ab8384442ee512fc0fc72deeb036110843d0e7ff Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx> Date: Sat, 20 Aug 2022 09:43:21 -0400 Subject: [PATCH] tracing/probes: Have kprobes and uprobes use $COMM too Both $comm and $COMM can be used to get current->comm in eprobes and the filtering and histogram logic. Make kprobes and uprobes consistent in this regard and allow both $comm and $COMM as well. Currently kprobes and uprobes only handle $comm, which is inconsistent with the other utilities, and can be confusing to users. Link: https://lkml.kernel.org/r/20220820134401.317014913@xxxxxxxxxxx Link: https://lore.kernel.org/all/20220820220442.776e1ddaf8836e82edb34d01@xxxxxxxxxx/ Cc: stable@xxxxxxxxxxxxxxx Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Tzvetomir Stoyanov <tz.stoyanov@xxxxxxxxx> Cc: Tom Zanussi <zanussi@xxxxxxxxxx> Fixes: 533059281ee5 ("tracing: probeevent: Introduce new argument fetching code") Suggested-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx> --- kernel/trace/trace_probe.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) Index: linux-test.git/kernel/trace/trace_probe.c =================================================================== --- linux-test.git.orig/kernel/trace/trace_probe.c 2022-08-22 12:13:58.964843406 -0400 +++ linux-test.git/kernel/trace/trace_probe.c 2022-08-22 12:15:44.808843824 -0400 @@ -361,7 +361,7 @@ static int parse_probe_vars(char *arg, c } } else ret = -EINVAL; - } else if (strcmp(arg, "comm") == 0) { + } else if (strcmp(arg, "comm") == 0 || strcmp(arg, "COMM") == 0) { if (strcmp(t->name, "string") != 0 && strcmp(t->name, "string_size") != 0) return -EINVAL; @@ -544,7 +544,7 @@ int traceprobe_parse_probe_arg(char *arg * The default type of $comm should be "string", and it can't be * dereferenced. */ - if (!t && strcmp(arg, "$comm") == 0) + if (!t && (strcmp(arg, "$comm") == 0 || strcmp(arg, "$COMM") == 0)) t = "string"; parg->type = find_fetch_type(t, ftbl); if (!parg->type) {
