From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marc Zyngier <marc.zyngier@arm.com>
Subject: Re: [PATCH] arm64: KVM: unregister notifiers in hyp mode teardown path
Date: Mon, 4 Apr 2016 15:33:41 +0100
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References: <1459777611-22592-1-git-send-email-sudeep.holla@arm.com>
 <5702726D.7000505@arm.com> <570278A4.9060600@arm.com>
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To: Sudeep Holla <sudeep.holla@arm.com>, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org
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On 04/04/16 15:22, Sudeep Holla wrote:
> 
> 
> On 04/04/16 14:55, Marc Zyngier wrote:
>> Hi Sudeep,
>>
>> On 04/04/16 14:46, Sudeep Holla wrote:
> 
> [...]
> 
>>> @@ -1270,12 +1279,7 @@ static int init_hyp_mode(void)
>>>   	free_boot_hyp_pgd();
>>>   #endif
>>>
>>> -	cpu_notifier_register_begin();
>>> -
>>> -	err = __register_cpu_notifier(&hyp_init_cpu_nb);
>>> -
>>> -	cpu_notifier_register_done();
>>> -
>>> +	err = register_cpu_notifier(&hyp_init_cpu_nb);
>>
>> We went from something like this to the cpu_notifier_register_begin/end
>> with 8146875de ("arm, kvm: Fix CPU hotplug callback registration").
>>
>> What makes it more acceptable now?
>>
> 
> Correct, but in the initial code even init_hyp_mode was protected under
> cpu_notifier_register_begin, but IIUC recent re-org eliminated the need
> for that and the above code exactly resembles what register_cpu_notifier
> does.
> 
> If that's not the case then we need to move cpu_notifier_register_begin
> further up and retain __register_cpu_notifier
> 
> I mainly changed it to keep it consistent with unregister call.

Right, thanks for the explanation. So FWIW:

Acked-by: Marc Zyngier <marc.zyngier@arm.com>

	M.
-- 
Jazz is not dead. It just smells funny...