Re: [PATCH] tracing: fprobe: Fix to init fprobe_ip_table earlier

From: Menglong Dong
Date: Thu Oct 02 2025 - 06:00:46 EST


On Thu, Oct 2, 2025 at 4:39 PM Masami Hiramatsu (Google)
<mhiramat@xxxxxxxxxx> wrote:
>
> From: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
>
> Since the fprobe_ip_table is used from module unloading in
> the failure path of load_module(), it must be initialized in
> the earlier timing than late_initcall(). Unless that, the
> fprobe_module_callback() will use an uninitialized spinlock of
> fprobe_ip_table.
>
> Initialize fprobe_ip_table in core_initcall which is the same
> timing as ftrace.
>
> Reported-by: kernel test robot <oliver.sang@xxxxxxxxx>
> Closes: https://lore.kernel.org/oe-lkp/202509301440.be4b3631-lkp@xxxxxxxxx

Don't we need a Fixes tag here?

The other part of this patch is LGTM.

Reviewed-by: Menglong Dong <menglong8.dong@xxxxxxxxx>

Thanks!
Menglong Dong

> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
> ---
> kernel/trace/fprobe.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c
> index 95e43814b85b..99d83c08b9e2 100644
> --- a/kernel/trace/fprobe.c
> +++ b/kernel/trace/fprobe.c
> @@ -847,4 +847,4 @@ static int __init fprobe_initcall(void)
> rhltable_init(&fprobe_ip_table, &fprobe_rht_params);
> return 0;
> }
> -late_initcall(fprobe_initcall);
> +core_initcall(fprobe_initcall);
>