From mboxrd@z Thu Jan  1 00:00:00 1970
From: Julien Grall <julien.grall@linaro.org>
Subject: Re: [PATCH for 4.5] xen/arm: Initialize the domain vgic
	lock
Date: Thu, 18 Dec 2014 12:05:36 +0000
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To: Ian Campbell <Ian.Campbell@citrix.com>
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Hi Ian,

On 18/12/2014 09:47, Ian Campbell wrote:
> On Wed, 2014-12-17 at 15:40 +0000, Julien Grall wrote:
>> The domain vgic lock is used uninitialized.
>>
>> Signed-off-by: Julien Grall <julien.grall@linaro.org>
>
> Acked-by: Ian Campbell <ian.campbell@citrix.com>
>
>> ---
>>      This is a bug fix for Xen 4.5 and Xen 4.4. The vgic lock is used
>>      unitialized. Luckily we only use the field "raw" which is reset to 0
>>      during the domain allocation.
>>
>>      There is no harm to apply for Xen 4.5 because it will correctly set
>>      the spin_lock structure for a later usage.
>
> By your above reasoning there is also no point, is there? That said, I
> think we should take this since as you say it is harmless and good
> practice to initialise spinlocks even if not strictly necessary.

It's necessary to initialize spinlocks, not all the field of the 
spinlock is using the value 0 at initialization time.

What I meant if the current usage is fine. But if we want to debug 
spinlock, it won't work.

Regards,

-- 
Julien Grall