Messages in this thread |  | | Date | Tue, 11 Sep 2018 15:36:32 +0900 | From | Masami Hiramatsu <> | Subject | Re: [PATCH -tip 5/5] kprobes: Don't call BUG_ON if there is a kprobe in use on free list |
| |
On Mon, 10 Sep 2018 14:23:56 +0200 Ingo Molnar <mingo@kernel.org> wrote:
> > * Masami Hiramatsu <mhiramat@kernel.org> wrote: > > > Instead of calling BUG_ON, if we find a kprobe in use on free kprobe > > list, just remove it from the list and keep it on kprobe hash list > > as same as other in-use kprobes. > > > > Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> > > --- > > kernel/kprobes.c | 8 +++++++- > > 1 file changed, 7 insertions(+), 1 deletion(-) > > > > diff --git a/kernel/kprobes.c b/kernel/kprobes.c > > index 63c342e5e6c3..e3420364b415 100644 > > --- a/kernel/kprobes.c > > +++ b/kernel/kprobes.c > > @@ -546,8 +546,14 @@ static void do_free_cleaned_kprobes(void) > > struct optimized_kprobe *op, *tmp; > > > > list_for_each_entry_safe(op, tmp, &freeing_list, list) { > > - BUG_ON(!kprobe_unused(&op->kp)); > > list_del_init(&op->list); > > + if (!kprobe_unused(&op->kp)) { > > + /* > > + * This must not happen, but if there is a kprobe > > + * still in use, keep it on kprobes hash list. > > + */ > > + continue; > > If this is an 'impossible' code path then I think it would make sense to add a WARN_ON_ONCE() > here.
I agree. This means something goes wrong. That is enough reason to warn user.
Thank you!
> > Thanks, > > Ingo
-- Masami Hiramatsu <mhiramat@kernel.org>
|  |