Re: [PATCH 0/3] mm: Rework {enabled,defrag}_{show,store}

[Gavin Shan <gshan@redhat.com>]

On 1/30/20 8:46 PM, Vlastimil Babka wrote:
> On 1/30/20 8:49 AM, Michal Hocko wrote:
>> On Thu 30-01-20 13:24:38, Gavin Shan wrote:
>>> The inappropriate settings can be accepted by "enabled" and "defrag"
>>> interface, as the following example shows. This series reworks the
>>> related functions and fixes the issue by the way.
>>
>> Do we really care? This is a root only interface and we do expect root
>> to know how to use the interface.
> 
> Also I think David already solved even this case with sysfs_streq() that
> Andrew suggested:
> 
> https://lore.kernel.org/linux-mm/alpine.DEB.2.21.2001171411020.56385@chino.kir.corp.google.com/
> 

Thanks for the linker. I didn't notice there already have a patch to address
the issue. Also, I perhaps post patch to improve the extendibility on top of
David's patch if you agree. Otherwise, it can be ignored.

By the way, it's nice to know sysfs_streq().

Thanks,
Gavin

>>>     # cat /sys/kernel/mm/transparent_hugepage/enabled
>>>       always [madvise] never
>>>     # echo neveroff > /sys/kernel/mm/transparent_hugepage/enabled
>>>     # cat /sys/kernel/mm/transparent_hugepage/enabled
>>>       always madvise [never]
>>>
>>> Gavin Shan (3):
>>>    mm: Rework {enabled,defrag}_store()
>>>    mm: Rework {enabled,defrag}_show()
>>>    mm: Rework setup_transparent_hugepage()
>>>
>>>   mm/huge_memory.c | 216 +++++++++++++++++++++++++++--------------------
>>>   1 file changed, 125 insertions(+), 91 deletions(-)
>>>
>>> -- 
>>> 2.23.0
>>>
>>
>