Hi.

On Thu, Jul 09, 2026 at 11:55:27AM +0200, Jiri Pirko <jiri@resnulli.us> wrote:
> index 993446ab66d0..4523c1884d67 100644
> --- a/Documentation/admin-guide/cgroup-v2.rst
> +++ b/Documentation/admin-guide/cgroup-v2.rst
> @@ -2752,6 +2752,13 @@ RDMA
>  The "rdma" controller regulates the distribution and accounting of
>  RDMA resources.
>  
> +When RDMA devices are isolated per network namespace (exclusive mode),
> +device names are unique only within a network namespace. The device lines
> +below are therefore scoped to the reading or writing process's network
> +namespace: only devices accessible from that namespace are listed, and a
> +limit is applied to the device of that name in that namespace. Configure
> +limits from the same network namespace as the workloads.

OK.

> --- a/include/linux/cgroup_rdma.h
> +++ b/include/linux/cgroup_rdma.h
> @@ -7,6 +7,7 @@
>  #define _CGROUP_RDMA_H
>  
>  #include <linux/cgroup.h>
> +#include <net/net_namespace.h>
>  
>  enum rdmacg_resource_type {
>  	RDMACG_RESOURCE_HCA_HANDLE,
> @@ -34,6 +35,15 @@ struct rdmacg_device {
>  	struct list_head	dev_node;
>  	struct list_head	rpools;
>  	char			*name;
> +	/*
> +	 * Net namespace the device belongs to. @netns_shared mirrors
> +	 * ib_devices_shared_netns: when true the device is visible from every
> +	 * net namespace (shared mode); otherwise @net is the only namespace
> +	 * that may see and configure it. @netns_shared is updated when the
> +	 * sharing mode changes, so use {READ,WRITE}_ONCE() to access it.
> +	 */
> +	possible_net_t		net;
> +	bool			netns_shared;

Any reason to store the netns_shared split per device? (IIUC, it's a
global parameter.)

Thanks,
Michal