Re: [PATCH] selftests/vm: Set mmap()'s fd as -1 for MAP_ANONYMOUS flag

From: Andrew Morton
Date: Tue Mar 28 2017 - 19:43:35 EST


On Fri, 24 Mar 2017 10:47:55 -0600 Shuah Khan <shuah@xxxxxxxxxx> wrote:

> > On Wed, Mar 15, 2017 at 10:19 PM, SeongJae Park <sj38.park@xxxxxxxxx> wrote:
> >> Man page of mmap() says that portable applications should ensure fd
> >> argument to be -1 if MAP_ANONYMOUS flag is set as below:
> >> ```
> >> The mapping is not backed by any file; its contents are initialized to
> >> zero. The fd and offset arguments are ignored; however, some
> >> implementations require fd to be -1 if MAP_ANONYMOUS (or
> >> MAP_ANON) is specified, and portable applications
> >> should ensure this.
> >> ```
> >>
> >> However, few mmap() calls under selftests/vm/ uses 0 as fd though they
> >> use MAP_ANONYMOUS flag. This commit changes the argument to be -1 as
> >> recommended.
>
> Hi Andrew,
>
> Do you have comments on this patch? Please Ack it if you would
> like me to take it thorugh ksefltest tree.

Acked-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>