From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH] mm: add VM_STATIC flag to vmalloc and prevent from
 removing the areas
Date: Tue, 11 Apr 2017 23:02:18 -0700
Message-ID: <20170412060218.GA16170@infradead.org>
References: <1491973350-26816-1-git-send-email-hoeun.ryu@gmail.com>
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To: Hoeun Ryu <hoeun.ryu@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Andrey Ryabinin <aryabinin@virtuozzo.com>, Andreas Dilger <adilger@dilger.ca>, Vlastimil Babka <vbabka@suse.cz>, Michal Hocko <mhocko@suse.com>, Chris Wilson <chris@chris-wilson.co.uk>, Ingo Molnar <mingo@kernel.org>, zijun_hu <zijun_hu@htc.com>, Matthew Wilcox <mawilcox@microsoft.com>, Thomas Garnier <thgarnie@google.com>, "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org

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"?