Re: linux-next: manual merge of the bpf-next tree with the origin tree

[Alexei Starovoitov]

On Tue, Apr 14, 2026 at 5:18 AM Mark Brown <broonie@xxxxxxxxxx> wrote:
>
> Hi all,
>
> Today's linux-next merge of the bpf-next tree got a conflict in:
>
>   include/linux/rcupdate.h
>
> between commit:
>
>   ad6ef775cbeff ("rcu-tasks: Document that RCU Tasks Trace grace periods now imply RCU grace periods")
>
> from the origin tree and commit:
>
>   57b23c0f612dc ("bpf: Retire rcu_trace_implies_rcu_gp()")
>
> from the bpf-next tree.
>
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging.  You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
>
> diff --combined include/linux/rcupdate.h
> index 18a85c30fd4f3,bfa765132de85..0000000000000
> --- a/include/linux/rcupdate.h
> +++ b/include/linux/rcupdate.h
> @@@ -205,15 -205,6 +205,6 @@@ static inline void exit_tasks_rcu_start
>   static inline void exit_tasks_rcu_finish(void) { }
>   #endif /* #else #ifdef CONFIG_TASKS_RCU_GENERIC */
>
> - /**
> -  * rcu_trace_implies_rcu_gp - does an RCU Tasks Trace grace period imply an RCU grace period?
> -  *
> -  * Now that RCU Tasks Trace is implemented in terms of SRCU-fast, a
> -  * call to synchronize_rcu_tasks_trace() is guaranteed to imply at least
> -  * one call to synchronize_rcu().
> -  */
> - static inline bool rcu_trace_implies_rcu_gp(void) { return true; }
> -

Right. I mentioned it in my bpf-next PR.

But how come you're saying it was discovered "today" ?

Paul's commit ad6ef775cbeff was committed to rcu tree on Mar 30,
while Kumar's 57b23c0f612dc was committed to bpf-next on Apr 7.

"today" is April 14.

My only explanation is that rcu tree was not in linux-next until today?!