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Subject: Re: [PATCH 1/5] mm/vmalloc.c: correct a few logic error for
 __insert_vmap_area()
To: David Rientjes <rientjes@google.com>
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Cc: zijun_hu@htc.com, Andrew Morton <akpm@linux-foundation.org>,
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From: zijun_hu <zijun_hu@zoho.com>
Message-ID: <c408c7df-3d1f-8985-a524-c6752e7809ba@zoho.com>
Date: Thu, 22 Sep 2016 07:55:26 +0800
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On 2016/9/22 7:15, David Rientjes wrote:
> On Thu, 22 Sep 2016, zijun_hu wrote:
> 
>>> We don't support inserting when va->va_start == tmp_va->va_end, plain and 
>>> simple.  There's no reason to do so.  NACK to the patch.
>>>
>> i am sorry i disagree with you because
>> 1) in almost all context of vmalloc, original logic treat the special case as normal
>>    for example, __find_vmap_area() or alloc_vmap_area()
> 
> The ranges are [start, end) like everywhere else.  __find_vmap_area() is 
> implemented as such for the passed address.  The address is aligned in 
> alloc_vmap_area(), there's no surprise here.  The logic is correct in 
> __insert_vmap_area().
> 
1) is the desire behavior of __insert_vmap_area() conform with that mentioned
   in my comments?
2) which way of code implementation can present the desire purpose more clear
   and more understandable?