Ah. we certainly misunderstand each other.
On 08/29, Jiri Olsa wrote:
>
> On Thu, Aug 29, 2024 at 05:20:33PM +0200, Oleg Nesterov wrote:
>
> SNIP
SNIP
> right.. if the event is not added by perf_trace_add on this cpu
> it won't go pass this point, so no problem for perf
Yes, and this is what I tried to verify. In your previous email you said
and I think the same will happen for perf record in this case where
instead of
running the program we will execute perf_tp_event
and I tried verify this can't happen. So no problem for perf ;)
> but the issue is with bpf program triggered earlier by return uprobe
Well, the issue with bpf program (with the bpf_prog_array_valid(call) code
in __uprobe_perf_func) was clear from the very beginning, no questions.
> and [1] patch seems to fix that
I'd say this patch fixes the symptoms, and it doesn't fix all the problems.
But I can't suggest anything better for bpf code, so I won't really argue.
However the changelog and even the subject is wrong.
> I sent out the bpf selftest that triggers the issue [2]
Thanks, I'll try take a look tomorrow.
Oleg.
