Re: nolibc patches, still possible for 6.5 ?

From: Paul E. McKenney
Date: Thu Jun 08 2023 - 12:42:13 EST


On Thu, Jun 08, 2023 at 10:21:57AM +0200, Willy Tarreau wrote:
> Hi Zhangjin,
>
> On Thu, Jun 08, 2023 at 04:13:37PM +0800, Zhangjin Wu wrote:
> > > I rebased the branch on top of 6.4-rc5 and got the same. I'm building
> > > with gcc-11.3.0 from kernel.org. I'm not sure whether this comes from
> > > my build environment or recent changes to the kernel, but I'm sure I
> > > haven't seen that error during 6.3-rc cycle. However, given that
> > > Zhangjin seems to have successfully built it for riscv, there might
> > > be something odd on my side.
> > >
> >
> > Sorry, The reason is that to speed up the kernel build+nolibc tests, a
> > local small config was customized for the first report,
>
> You don't have to be sorry for this! The more diversity in configs, the
> more bugs are discovered before they hit users.

And I couldn't agree more! Again, thank you both!

Thanx, Paul

> > it may not
> > trigger the above issue, in the later report about the v4 rv32 compile
> > support [1], I did test 'run' target with the default defconfig and
> > reported the same failure as bove, this is the note I pasted there:
> >
> > ---
> > Did compile test for aarch64, rv32 and rv64, include run-user and run.
> >
> > Note, this is required with the default config from the
> > 20230606-nolibc-rv32+stkp7a branch of [5]:
> >
> > diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
> > index ce02bb09651b..72bd8fe0cad6 100644
> > --- a/kernel/rcu/tasks.h
> > +++ b/kernel/rcu/tasks.h
> > @@ -1934,11 +1934,13 @@ void show_rcu_tasks_gp_kthreads(void)
> > }
> > #endif /* #ifndef CONFIG_TINY_RCU */
> >
> > +#ifdef CONFIG_TASKS_RCU
> > struct task_struct *get_rcu_tasks_gp_kthread(void)
> > {
> > return rcu_tasks.kthread_ptr;
> > }
> > EXPORT_SYMBOL_GPL(get_rcu_tasks_gp_kthread);
> > +#endif
> >
> > #ifdef CONFIG_PROVE_RCU
> > struct rcu_tasks_test_desc {
> > ---
>
> Indeed, I initially didn't make the connection regarding this, because
> you mentioned the fix but not the problem, so I didn't remember to take
> any particular care about this.
>
> > I have seen Paul have known the cause of the above issue in your later
> > discussion and you found a better solution to avoid such failures,
> > congrats!
>
> Yes apparently Paul is aware of it so that's all what I wanted to make
> sure of.
>
> Thanks!
> Willy
>
> PS: I'll hopefully check your other series later today