Re: [PATCH] x86: fix cpu-hotplug regression

["Andreas Herrmann" <andreas.herrmann3@amd.com>]

On Fri, Nov 09, 2007 at 12:16:34PM -0800, Andrew Morton wrote:
> On Wed, 7 Nov 2007 23:15:38 +0900
> "Akinobu Mita" <akinobu.mita@gmail.com> wrote:
> 
> > > [PATCH] x86: fix cpu hotplug regression (don't call mce_create_device on CPU_UP_PREPARE)
> > >
> > > Fix regression introduced with d435d862baca3e25e5eec236762a43251b1e7ffc
> > > ("cpu hotplug: mce: fix cpu hotplug error handling").
> > >
> > > For CPUs not brought up during boot (using maxcpus and additional_cpus
> > > parameters) we don't know whether mce is supported or not at "CPU_UP_PREPARE"-time.
> > > Thus mce_cpu_callback should be called after the CPU is online.
> > 
> > Thank you for finding and fixing the problem.
> > I added two fixes to your patch:
> > 
> > - Avoid mce_remove_device() for the CPU that is not correctly initialized
> >   by mce_create_device() failure.
> > 
> > - make CPU_ONLINE callback always return NOTIFY_OK.
> >   Because CPU_ONLINE callback return value is always ignored.
> > 
> > > Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
> > 
> > [akinobu.mita@gmail.com: make CPU_ONLINE callback always return NOTIFY_OK]
> > [akinobu.mita@gmail.com: avoid mce_remove_device() for not initialized device]
> > 
> > Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> 
> Andreas, could you please review and preferably runtime-test this new
> version?

I'll test it today ...

> Assuming that all goes well could one of you please prepare a final patch
> with a complete changelog?

... and can send a final patch after successful testing.


Regards,

Andreas


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