Re: [PATCH v9 0/8] Parallel CPU bringup for x86_64

[Oleksandr Natalenko]

Hello.

On 20.02.2023 21:31, David Woodhouse wrote:
> On Mon, 2023-02-20 at 17:40 +0100, Oleksandr Natalenko wrote:
> > On pondělí 20. února 2023 17:20:13 CET David Woodhouse wrote:
> > > On Mon, 2023-02-20 at 17:08 +0100, Oleksandr Natalenko wrote:
> > > >
> > > > I've applied this to the v6.2 kernel, and suspend/resume broke on
> > > > my
> > > > Ryzen 5950X desktop. The machine suspends just fine, but on
> > > > resume
> > > > the screen stays blank, and there's no visible disk I/O.
> > > >
> > > > Reverting the series brings suspend/resume back to working state.
> > >
> > > Hm, thanks. What if you add 'no_parallel_bringup' on the command
> > > line?
> >
> > If the `no_parallel_bringup` param is added, the suspend/resume
> > works.
>
> Thanks for the testing. Can I ask you to do one further test: apply the
> series only as far as patch 6/8 'x86/smpboot: Support parallel startup
> of secondary CPUs'.
>
> That will do the new startup asm sequence where each CPU finds its own
> per-cpu data so it *could* work in parallel, but doesn't actually do
> the bringup in parallel yet.

With patches 1 to 6 (including) applied and no extra cmdline params 
added the resume doesn't work.

> Does your box have a proper serial port?

No, sorry. I know it'd help with getting logs, and I do have a 
serial-to-USB cable that I use for another machine, but in this one the 
port is not routed to outside. I think I can put a header there as the 
motherboard does have pins, but I'd have to buy one first. In theory, I 
can do that, but that won't happen within the next few weeks.

P.S. Piotr Gorski (in Cc) also reported this: "My friend from CachyOS 
can confirm bugs with smpboot patches. AMD FX 6300 only shows 1 core 
when using smp boot patchset". Probably, he can reply to this thread and 
provide more details.

--
  Oleksandr Natalenko (post-factum)