Re: [PATCH] kprobes: avoid crash when rmmod/insmod modules after ftrace_disabled

[Masami Hiramatsu (Google) <mhiramat@kernel.org>]

On Wed, 3 Dec 2025 10:37:05 +0800
yebin <yebin@huaweicloud.com> wrote:

> >>> diff --git a/kernel/kprobes.c b/kernel/kprobes.c
> >>> index ab8f9fc1f0d1..17d451553389 100644
> >>> --- a/kernel/kprobes.c
> >>> +++ b/kernel/kprobes.c
> >>> @@ -1104,6 +1104,10 @@ static int __disarm_kprobe_ftrace(struct kprobe *p, struct ftrace_ops *ops,
> >>>    	int ret;
> >>>
> >>>    	lockdep_assert_held(&kprobe_mutex);
> >>> +	if (unlikely(kprobe_ftrace_disabled)) {
> >>> +		/* Now ftrace is disabled forever, disarm is already done. */
> >>> +		return 0;
> >>> +	}
> >>>
> >>>    	if (*cnt == 1) {
> >>>    		ret = unregister_ftrace_function(ops);
> >>>
> >
> > This one, it should fix simply.
> >
> I tested it and it can solve the problem. This is indeed a good solution 
> that reuses the original code.
> Do you want me to send a new patch version according to your proposal?

OK, I'll send it with some tags which is required for this fix.
Please add your tested-by on that.

Thank you,

> > Thank you,
> >
> >>>
> >>
> >
> >
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>