On 6/19/22 3:56 AM, chuang wrote:
On Sun, Jun 19, 2022 at 5:17 AM Jiri Olsa <olsajiri@xxxxxxxxx> wrote:
just curious.. is that because of ipmodify flag on ftrace_ops?
AFAICS that be a poblem just for kretprobes, cc-ing Masami
Yes, the core reason is caused by ipmodify flag (not only for kretprobes).
Before commit 0bc11ed5ab60 ("kprobes: Allow kprobes coexist with
livepatch"), it's very easy to trigger this problem.
The kprobe has other problems and is communicating with Masami.
With this fix, whenever an error is returned after
add_kprobe_event_legacy(), this guarantees cleanup of the kprobe
event.
The details from this follow-up conversation should definitely be part of
the commit description, please add them to a v2 as otherwise context is
missing if we look at the commit again in say few months from now. Also,
would be good if Masami could provide ack given 0bc11ed5ab60.
Thanks,
Daniel
