Re: [RFC PATCH for 4.15 00/24] Restartable sequences and CPU op vector v11

[Paul Turner]

I have some comments that apply to many of the threads.
I've been fully occupied with a wedding and a security issue; but I'm
about to be free to spend the majority of my time on RSEQ things.
I was sorely hoping that day would be today.  But it's looking like
I'm still a day or two from being free for this.
Thank you for the extensive clean-ups and user-side development.  I
have some updates on these topics also.

- Paul

On Tue, Nov 14, 2017 at 1:15 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
> On Tue, Nov 14, 2017 at 1:08 PM, Linus Torvalds
> <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>> On Tue, Nov 14, 2017 at 12:03 PM, Mathieu Desnoyers
>> <mathieu.desnoyers@xxxxxxxxxxxx> wrote:
>>> Here is the last RFC round of the updated rseq patchset containing:
>>
>> Andy? You were the one with concerns here and said you'd have
>> something else ready for comparison.
>>
>
> I had a long discussion with Mathieu and KS and I think that this is a
> good compromise.  I haven't reviewed the series all that carefully,
> but I think the idea is sound.
>
> Basically, event_counter is gone (to be re-added in a later kernel if
> it really ends up being necessary, but it looks like it may primarily
> be a temptation to write subtly incorrect user code and to see
> scheduling details that shouldn't be readily exposed rather than a
> genuinely useful feature) and the versioning mechanism for the asm
> critical section bit is improved.  My crazy proposal should be doable
> on top of this if there's demand and if anyone wants to write the
> gnarly code involved.
>
> IOW no objection from me as long as those changes were made, which I
> *think* they were.  Mathieu?