Re: [PATCH] Documentation: update the description of TracerPid in procfs.rst

From: Jonathan Corbet
Date: Tue Nov 15 2022 - 17:09:12 EST


Chen Linxuan <chenlinxuan@xxxxxxxxxxxxx> writes:

> When the tracer of process is outside of current pid namespace, field
> `TracerPid` in /proc/<pid>/status will be 0, too, just like this process
> not have been traced.
>
> This is because that function `task_pid_nr_ns` used to get the pid of
> tracer will return 0 in this situation.
>
> Co-authored-by: Yuan Haisheng <heysion@xxxxxxxxxx>
> Signed-off-by: Chen Linxuan <chenlinxuan@xxxxxxxxxxxxx>
> ---
> Documentation/filesystems/proc.rst | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst
> index 898c99eae8e4..e98e0277f05e 100644
> --- a/Documentation/filesystems/proc.rst
> +++ b/Documentation/filesystems/proc.rst
> @@ -245,7 +245,8 @@ It's slow but very precise.
> Ngid NUMA group ID (0 if none)
> Pid process id
> PPid process id of the parent process
> - TracerPid PID of process tracing this process (0 if not)
> + TracerPid PID of process tracing this process (0 if not, or
> + the tracer is outside of the current pid namespace)

Applied, thanks.

jon