Re: [PATCH] nvdimm: constify device_type structures

[Dan Williams]

On Tue, Jan 24, 2017 at 6:37 PM, Joe Perches <joe@xxxxxxxxxxx> wrote:
> On Wed, 2017-01-25 at 00:54 +0530, Bhumika Goyal wrote:
>> Declare device_type structure as const as it is only stored in the
>> type field of a device structure. This field is of type const, so add
>> const to declaration of device_type structure.
>>
>> File size before:
>>   text           data     bss     dec     hex filename
>>   19278          3199      16   22493    57dd nvdimm/namespace_devs.o
>>
>> File size after:
>>   text           data     bss     dec     hex filename
>>   19929          3160      16   23105    5a41 nvdimm/namespace_devs.o
>
> Fine, but are you sure about the sizes?
>
> It seems odd the text went up 651 bytes
> while the data went down just 39 bytes.
>

Right, the size data wasn't why I applied it. It was the general rule
of "make function pointer data read-only whenever possible to
eliminate a kernel attack vector".  Bhumika, you might want to mention
this as the motivating reason to apply the patch if you do more of
these changes.