On 08/07, Andrii Nakryiko wrote: > > Yes, I was waiting for more of Peter's comments, but I guess I'll just > send a v2 today. OK, > I'll probably include the SRCU+timeout logic for > return_instances, and maybe lockless VMA parts as well. Well, feel free to do what you think right, but perhaps it would be better to push this series first? at least 1-4. As for lockless VMA. To me this needs more discussions. I didn't read your conversation with Peter and Suren carefully, but I too have some concerns. Most probably I am wrong, and until I saw this thread I didn't even know that vm_area_free() uses call_rcu() if CONFIG_PER_VMA_LOCK, but still. > > As for 8/8 - I leave it to you and Peter. I'd prefer SRCU though ;) > > Honestly curious, why the preference? Well, you can safely ignore me, but since you have asked ;) I understand what SRCU does, and years ago I even understood (I hope) the implementation. More or less the same for rcu_tasks. But as for the _trace flavour, I simply fail to understand its semantics. > BTW, while you are here :) What can you say about > current->sighand->siglock use in handle_singlestep()? It should die, and this looks simple. I disagree with the patches from Liao, see the https://lore.kernel.org/all/20240801082407.1618451-1-liaochang1@xxxxxxxxxx/ thread, but I agree with the intent. IMO, we need a simple "bool restore_sigpending" in uprobe_task, it will make the necessary changes really simple. (To clarify. In fact I think that a new TIF_ or even PF_ flag makes more sense, afaics it can have more users. But I don't think that uprobes can provide enough justification for that right now) Oleg.
