[patch 00/37] cpu/hotplug, x86: Reworked parallel CPU bringup

[Thomas Gleixner]

On Tue, Apr 18 2023 at 08:58, Thomas Gleixner wrote:
> On Mon, Apr 17 2023 at 19:40, Paul Menzel wrote:
>> Am 17.04.23 um 16:48 schrieb Thomas Gleixner:
>>
>>> On Mon, Apr 17 2023 at 13:19, Paul Menzel wrote:
>>>> Am 15.04.23 um 01:44 schrieb Thomas Gleixner:
>>>> [    0.258193] smpboot: CPU0: AMD A6-6400K APU with Radeon(tm) HD
>>>> Graphics (family: 0x15, model: 0x13, stepping: 0x1)
>>>> […]
>>>> [    0.259329] smp: Bringing up secondary CPUs ...
>>>> [    0.259527] x86: Booting SMP configuration:
>>>> [    0.259528] .... node  #0, CPUs:      #1
>>>> [    0.261007] After schedule_preempt_disabled
>>>> [   10.260990] CPU1 failed to report alive state
>>> 
>>> Weird. CPU1 fails to come up and report that it has reached the
>>> synchronization point.
>>> 
>>> Does it work when you add cpuhp.parallel=off on the kernel command line?
>>
>> Yes, the ten seconds delay is gone with `cpuhp.parallel=off`.
>>
>> There was a patch set in the past, that worked on that device. I think 
>> up to v4 it did *not* work at all and hung [1]. I need some days to 
>> collect the results again.
>
> Can you please apply the patch below on top of the pile remove the
> command line option again?

Bah. That patch does not make any sense at all. Not enough coffee.

Can you please provide the output of cpuid?

Thanks,

        tglx