Re: [PATCH 3/3] riscv: Allow to enable PREEMPT_RT.

[Palmer Dabbelt]

On Fri, 06 Sep 2024 11:48:03 PDT (-0700), Palmer Dabbelt wrote:
> On Fri, 06 Sep 2024 08:13:24 PDT (-0700), namcao@xxxxxxxxxxxxx wrote:
> > On Fri, Sep 06, 2024 at 12:59:06PM +0200, Sebastian Andrzej Siewior wrote:
> > > It is really time.
> > >
> > > riscv has all the required architecture related changes, that have been
> > > identified over time, in order to enable PREEMPT_RT. With the recent
> > > printk changes, the last known road block has been addressed.
> > >
> > > Allow to enable PREEMPT_RT on riscv.
> > >
> > > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
> >
> > With the printk patches applied:
> >
> > Tested-by: Nam Cao <namcao@xxxxxxxxxxxxx> # Visionfive 2
>
>
> Thanks.  LMK if you guys want me to take this through the RISC-V tree,
> but no big deal if you want it somewhere else -- and if there's some
> dependencies already going in through some sort of RT tree maybe that's
> just easier.  So
>
> Acked-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>
>
> I don't have a test setup yet, but I figure it's a new feature so I'll
> just flip it on as a config post-rc1.  Presumably this just works in the
> QEMU virt board, or is there some wizardry I'll need to copy?

and it breaks my boot test script.  Looks like it's actually working 
mostly fine, I'm just not getting the "reboot: System halted" message 
that I'm checking for to make sure the system actually went down 
cleanly.

I'm not sure if this is expected behavior in RT land, or if we've got 
some sort of bug.  It sort of smells like we're losing the last printk() 
line...

> > Best regards,
> > Nam