On Sun, Oct 9, 2022 at 3:00 PM Jiri Olsa <jolsa@xxxxxxxxxx> wrote:
>
> Currently ftrace_lookup_symbols iterates only over core symbols,
> adding module_kallsyms_on_each_symbol call to check on modules
> symbols as well.
>
> Also removing 'args.found == args.cnt' condition, because it's
> already checked in kallsyms_callback function.
>
> Also removing 'err < 0' check, because both *kallsyms_on_each_symbol
> functions do not return error.
>
> Reported-by: Martynas Pumputis <m@xxxxxxxxx>
> Signed-off-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Acked-by: Song Liu <song@xxxxxxxxxx>
> ---
> kernel/trace/ftrace.c | 11 ++++++-----
> 1 file changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 447d2e2a8549..6efdba4666f4 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -8292,17 +8292,18 @@ static int kallsyms_callback(void *data, const char *name,
> int ftrace_lookup_symbols(const char **sorted_syms, size_t cnt, unsigned long *addrs)
> {
> struct kallsyms_data args;
> - int err;
> + int found_all;
>
> memset(addrs, 0, sizeof(*addrs) * cnt);
> args.addrs = addrs;
> args.syms = sorted_syms;
> args.cnt = cnt;
> args.found = 0;
> - err = kallsyms_on_each_symbol(kallsyms_callback, &args);
> - if (err < 0)
> - return err;
> - return args.found == args.cnt ? 0 : -ESRCH;
> + found_all = kallsyms_on_each_symbol(kallsyms_callback, &args);
> + if (found_all)
> + return 0;
> + found_all = module_kallsyms_on_each_symbol(kallsyms_callback, &args);
> + return found_all ? 0 : -ESRCH;
We probably need some comments about kallsym_callback and
ftrace_lookup_symbols. It took me a while to confirm the logic for
found_all.
> }
>
> #ifdef CONFIG_SYSCTL
> --
> 2.37.3
>
