Re: [PATCH] proc.5: add "wf" to VmFlags in /proc/[pid]/smaps

[Ian Rogers]

On Thu, May 21, 2020 at 3:25 PM Ian Rogers <irogers@xxxxxxxxxx> wrote:
>
> This patch documents a flag added in the following kernel commit:
>
> commit d2cd9ede6e193dd7d88b6d27399e96229a551b19
> Author: Rik van Riel <riel@xxxxxxxxxx>
> Date:   Wed Sep 6 16:25:15 2017 -0700
>
>     mm,fork: introduce MADV_WIPEONFORK
>
> This was already documented in man2/madvise.2 in the commit:
>
> commit c0c4f6c29c494c466f3a2a6273c5b55b76a72927
> Author: Rik van Riel <riel@xxxxxxxxxx>
> Date:   Tue Sep 19 20:32:00 2017 +0200
>
>     madvise.2: Document MADV_WIPEONFORK and MADV_KEEPONFORK
>
> Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>

Doing a quick audit of fs/proc/task_mmu.c having noticed this flag was
missing I note:
 - "mp" isn't documented, only possible with INTEL_MPX
 - "nl" is documented but not present in show_smap_vma_flags
 - "um" and "uw" aren't documented

Thanks,
Ian

> ---
>  man5/proc.5 | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/man5/proc.5 b/man5/proc.5
> index 46d603f28..3e5b91af0 100644
> --- a/man5/proc.5
> +++ b/man5/proc.5
> @@ -2020,6 +2020,7 @@ encoded using the following two-letter codes:
>      ht  - area uses huge tlb pages
>      nl  - non-linear mapping
>      ar  - architecture specific flag
> +    wf  - wipe on fork
>      dd  - do not include area into core dump
>      sd  - soft-dirty flag
>      mm  - mixed map area
> --
> 2.27.0.rc0.183.gde8f92d652-goog
>