Re: [PATCH 1/3 RESEND] sched: Remove __rcu annotation from cred pointer

From: Richard Guy Briggs
Date: Mon May 25 2020 - 09:18:09 EST


On 2020-05-24 13:41, Amol Grover wrote:
> On Thu, Apr 02, 2020 at 11:26:38AM +0530, Amol Grover wrote:
> > task_struct::cred (subjective credentials) is *always* used
> > task-synchronously, hence, does not require RCU semantics.
> >
> > task_struct::real_cred (objective credentials) can be used in
> > RCU context and its __rcu annotation is retained.
> >
> > However, task_struct::cred and task_struct::real_cred *may*
> > point to the same object, hence, the object pointed to by
> > task_struct::cred *may* have RCU delayed freeing.
> >
> > Suggested-by: Jann Horn <jannh@xxxxxxxxxx>
> > Co-developed-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
> > Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
> > Signed-off-by: Amol Grover <frextrite@xxxxxxxxx>
>
> Hello everyone,
>
> Could you please go through patches 1/3 and 2/3 and if deemed OK, give
> your acks. I sent the original patch in beginning of February (~4 months
> back) and resent the patches again in beginning of April due to lack of
> traffic. Paul Moore was kind enough to ack twice - the 3/3 and its
> resend patch. However these 2 patches still remain. I'd really
> appreciate if someone reviewed them.

I asked on April 3 which upstream tree you expect this patchset to go
through and I did not see a reply. Do you have a specific target or is
the large addressee list assuming someone else is taking this set? All
we have seen is that it is not intended to go through the audit tree.

> Thanks
> Amol

- RGB

--
Richard Guy Briggs <rgb@xxxxxxxxxx>
Sr. S/W Engineer, Kernel Security, Base Operating Systems
Remote, Ottawa, Red Hat Canada
IRC: rgb, SunRaycer
Voice: +1.647.777.2635, Internal: (81) 32635