mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

tracing/probes: Fix tracepoint event with $arg* to fetch correct argument 

To hide the first dummy 'data' argument on the tracepoint probe events,
the BTF argument array was modified (skip the first argument for tracepoint),
but the '$arg*' meta argument parser missed that.

Fix to increment the argument index if it is tracepoint probe. And decrement
the index when searching the type of the argument.

Link: https://lore.kernel.org/all/168657113778.3038017.12245893750241701312.stgit@mhiramat.roam.corp.google.com/

Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
This commit is contained in:
Masami Hiramatsu (Google) 2023-06-12 20:58:57 +09:00
parent a2bd0c08a4
commit 53431798f4
1 changed files with 8 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
kernel/trace/trace_probe.c
View File

@ -456,7 +456,10 @@ static int parse_btf_arg(const char *varname, struct fetch_insn *code,
if (name && !strcmp(name, varname)) {
code->op = FETCH_OP_ARG;
code->param = i;
if (ctx->flags & TPARG_FL_TPOINT)
code->param = i + 1;
else
code->param = i;
return 0;
}
}
@ -470,8 +473,11 @@ static const struct fetch_type *parse_btf_arg_type(int arg_idx,
struct btf *btf = traceprobe_get_btf();
const char *typestr = NULL;
if (btf && ctx->params)
if (btf && ctx->params) {
if (ctx->flags & TPARG_FL_TPOINT)
arg_idx--;
typestr = type_from_btf_id(btf, ctx->params[arg_idx].type);
}
return find_fetch_type(typestr, ctx->flags);
}