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Date: Mon, 07 Dec 2009 10:20:36 -0600
From: Anthony Liguori <anthony@codemonkey.ws>
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Subject: Re: [Qemu-devel] [PATCH] Permit zero-sized qemu_malloc() & friends
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To: Avi Kivity <avi@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Paul Brook <paul@codesourcery.com>, Markus Armbruster <armbru@redhat.com>, qemu-devel@nongnu.org

Avi Kivity wrote:
>> Covering every qemu_malloc instance this close to the GA is too 
>> risky.  I agree that having separate behavior is less than ideal but 
>> I think it's the only sane way forward.
>>
>
> I don't understand why.  What's so insane about Markus' patch?  
> Allowing size=0 for both developer and production builds?

There is a bug here.  Callers are calling qemu_malloc incorrectly.

There is an open discussion about how to address it--fix all callers of 
qemu_malloc() or allow size=0.  Since there isn't agreement, a 
compromise of sticking to the current behavior for the development tree, 
and using the later for production since we can't guarantee the former 
seems reasonable.

> It seems like the least risky, least change approach to me.  Exactly 
> what we want for 0.12.

The risk is that everyone will agree to this approach in the next two 
weeks.  I'm fairly certain no amount of discussion on qemu-devel is 
going to lead to that.

>>> In addition, Markus' patch should be applied to master to avoid 
>>> regressions while the code is converted.
>>
>> Let's separate that discussion as it's an independent consideration.
>>
>
> I've asked for qemu-malloc-discuss@vger.kernel.org to be created for 
> this purpose.

:-)

Regards,

Anthony Liguori