Re: [patch v2] mremap.2: Add description of old_size == 0 functionality

[Michal Hocko]

On Wed 20-09-17 09:25:42, Michael Kerrisk wrote:
[...]
>     BUGS
>        Before Linux 4.14, if old_size was zero and the  mapping  referred
>        to  by  old_address  was  a private mapping (mmap(2) MAP_PRIVATE),
>        mremap() created a new private mapping unrelated to  the  original
>        mapping.   This behavior was unintended and probably unexpected in
>        user-space applications (since the intention  of  mremap()  is  to
>        create  a new mapping based on the original mapping).  Since Linux
>        4.14, mremap() fails with the error EINVAL in this scenario.
> 
> Does that seem okay?

sorry to be late but yes this wording makes perfect sense to me.
-- 
Michal Hocko
SUSE Labs