Re: [PATCH] mm: add VM_STATIC flag to vmalloc and prevent from removing the areas

From: Hoeun Ryu
Date: Wed Apr 12 2017 - 07:42:34 EST



> On Apr 12, 2017, at 3:02 PM, Christoph Hellwig <hch@xxxxxxxxxxxxx> 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.