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Date: Tue, 28 Nov 2023 14:51:52 +0000
From: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
To: "Russell King (Oracle)" <linux@armlinux.org.uk>
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Subject: Re: [PATCH RFC 08/22] drivers: base: Implement weak
 arch_unregister_cpu()
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> > +
> > +#ifdef CONFIG_HOTPLUG_CPU
> > +void __weak arch_unregister_cpu(int num)
> > +{
> > +	unregister_cpu(&per_cpu(cpu_devices, num));
> > +}
> > +#endif /* CONFIG_HOTPLUG_CPU */  
> 
> I have previously asked the question whether we should provide a
> stub weak function for the !HOTPLUG_CPU case for this, which would
> alleviate the concerns around if (IS_ENABLED()) in some of the later
> hotplug vCPU patches... which failed to get _any_ responses.
> 
> So, I'm now going to deem the comment I received about if (IS_ENABLED())
> potentially causing issues to be unimportant, and thus there's no
> need for a stub weak function. If we start getting compile errors,
> then we can address the issue at that point. So far, however, the
> kernel build bot has not identified that this as an issue... and it's
> been chewing on this entire patch set for well over a month now.
> 

Make sense to fix this only if it's a real problem. 
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>