Re: [PATCH man-pages 1/5] ioctl_userfaultfd.2: update description of shared memory areas

From: Michael Kerrisk (man-pages)
Date: Mon May 01 2017 - 14:33:49 EST


Hello Mike,

I've applied this patch, but have a question.

On 05/01/2017 07:43 AM, Mike Rapoport wrote:
> Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
> ---
> man2/ioctl_userfaultfd.2 | 13 +++++++++++--
> 1 file changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/man2/ioctl_userfaultfd.2 b/man2/ioctl_userfaultfd.2
> index 889feb9..6edd396 100644
> --- a/man2/ioctl_userfaultfd.2
> +++ b/man2/ioctl_userfaultfd.2
> @@ -181,8 +181,17 @@ virtual memory areas
> .TP
> .B UFFD_FEATURE_MISSING_SHMEM
> If this feature bit is set,
> -the kernel supports registering userfaultfd ranges on tmpfs
> -virtual memory areas
> +the kernel supports registering userfaultfd ranges on shared memory areas.
> +This includes all kernel shared memory APIs:
> +System V shared memory,
> +tmpfs,
> +/dev/zero,
> +.BR mmap(2)
> +with
> +.I MAP_SHARED
> +flag set,
> +.BR memfd_create (2),
> +etc.
>
> The returned
> .I ioctls

Does the change in this patch represent a change that occurred in
Linux 4.11? If so, I think this needs to be said explicitly in the text.

Cheers,

Michael



--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/