[CRIU] [PATCH 01/14] namespace: don't fail if a namespace isn't supported by kernel

[Pavel Emelyanov]

On 10/14/2014 03:38 PM, Andrey Vagin wrote:
> CRIU reads /proc/pid/ns/[NS] and fails of a link is not exist.
> 
> Signed-off-by: Andrey Vagin <avagin at openvz.org>
> ---
>  namespaces.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/namespaces.c b/namespaces.c
> index 1feb165..bd7d86e 100644
> --- a/namespaces.c
> +++ b/namespaces.c
> @@ -230,6 +230,11 @@ static unsigned int __get_ns_id(int pid, struct ns_desc *nd, struct ns_id **ns)
>  	sprintf(ns_path, "ns/%s", nd->str);
>  	ret = readlinkat(proc_dir, ns_path, ns_id, sizeof(ns_id));
>  	if (ret < 0) {
> +		if (errno == ENOENT) {
> +			/* The namespace is unsupported */
> +			kid = 0;

Then it should "live" in CRIU's namespace.

> +			goto out;
> +		}
>  		pr_perror("Can't readlink ns link");
>  		return 0;
>  	}
> @@ -237,6 +242,7 @@ static unsigned int __get_ns_id(int pid, struct ns_desc *nd, struct ns_id **ns)
>  	kid = parse_ns_link(ns_id, ret, nd);
>  	BUG_ON(!kid);
>  
> +out:
>  	return generate_ns_id(pid, kid, nd, ns);
>  }
>  
>