Re: [PATCH 5/4] update ksm userspace interfaces

Izik Eidus
2009-04-03T10:54:46Z

Gerd Hoffmann wrote:
> Izik Eidus wrote:
>
>> The main problem that ksm will face when removing the fd interface is:
>> right now when you register memory into ksm, you open fd, and then ksm
>> do get_task_mm(), we will do mmput when the file will be closed
>>
>
> Did you test whenever it really cleans up in case you "kill -9 qemu"?
>
> I recently did something simliar with the result that the extra
> reference hold on mm_struct prevented the process memory from being
> zapped ...
>
> cheers,
> Gerd
>
Did you use mmput() after you called get_task_mm() ???
get_task_mm() do nothing beside atomic_inc(&mm->mm_users);

and mmput() do nothing beside dec this counter and check if no reference
are available to this....

Am i missing anything?