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Subject: Re: [PATCH] mm: add VM_STATIC flag to vmalloc and prevent from
 removing the areas
From: Ho-Eun Ryu <hoeun.ryu@gmail.com>
In-Reply-To: <20170412173151.GA23054@infradead.org>
Date: Thu, 13 Apr 2017 10:03:14 +0900
Cc: Andrew Morton <akpm@linux-foundation.org>,
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To: Christoph Hellwig <hch@infradead.org>
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> On 13 Apr 2017, at 2:31 AM, Christoph Hellwig <hch@infradead.org> wrote:
> 
> On Wed, Apr 12, 2017 at 08:42:08PM +0900, Hoeun Ryu wrote:
>> 
>>> On Apr 12, 2017, at 3:02 PM, Christoph Hellwig <hch@infradead.org> wrote:
>>> 
>>>> On Wed, Apr 12, 2017 at 02:01:59PM +0900, Hoeun Ryu wrote:
>>>> vm_area_add_early/vm_area_register_early() are used to reserve vmalloc area
>>>> during boot process and those virtually mapped areas are never unmapped.
>>>> So `OR` VM_STATIC flag to the areas in vmalloc_init() when importing
>>>> existing vmlist entries and prevent those areas from being removed from the
>>>> rbtree by accident.
>>> 
>>> How would they be removed "by accident"?
>> 
>> I don't mean actual use-cases, but I just want to make it robust against like programming errors.
> 
> Oh, ok.  The patch makes sense then, although the changelog could use
> a little update.

OK, I will.
Any other suggestions for code itself ?