Re: [PATCH 4/5] Move the user namespace under the option

[Cedric Le Goater <clg@fr.ibm.com>]

Pavel Emelyanov wrote:
> We currently have a CONFIG_USER_NS option. Just rename it 
> into CONFIG_NAMESPACES_EXPERIMANTAL and move the init_user_ns
> into user.c file to make the kernel compile and work without 
> the namespaces support.
> 
> Signed-off-by: Pavel Emelyanov <xemul@openvz.org>


Acked-by: Cedric Le Goater <clg@fr.ibm.com>

Thanks !

C. 

> ---
> 
> diff --git a/include/linux/user_namespace.h b/include/linux/user_namespace.h
> index b5f41d4..dda160c 100644
> --- a/include/linux/user_namespace.h
> +++ b/include/linux/user_namespace.h
> @@ -17,7 +17,7 @@ struct user_namespace {
> 
>  extern struct user_namespace init_user_ns;
> 
> -#ifdef CONFIG_USER_NS
> +#ifdef CONFIG_NAMESPACES_EXPERIMENTAL
> 
>  static inline struct user_namespace *get_user_ns(struct user_namespace *ns)
>  {
> diff --git a/init/Kconfig b/init/Kconfig
> index 684ccfb..0db1c3b 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -206,15 +206,6 @@ config TASK_IO_ACCOUNTING
> 
>  	  Say N if unsure.
> 
> -config USER_NS
> -	bool "User Namespaces (EXPERIMENTAL)"
> -	default n
> -	depends on EXPERIMENTAL
> -	help
> -	  Support user namespaces.  This allows containers, i.e.
> -	  vservers, to use user namespaces to provide different
> -	  user info for different servers.  If unsure, say N.
> -
>  config AUDIT
>  	bool "Auditing support"
>  	depends on NET
> diff --git a/kernel/Makefile b/kernel/Makefile
> index 76f782f..5817bfe 100644
> --- a/kernel/Makefile
> +++ b/kernel/Makefile
> @@ -4,7 +4,7 @@
> 
>  obj-y     = sched.o fork.o exec_domain.o panic.o printk.o profile.o \
>  	    exit.o itimer.o time.o softirq.o resource.o \
> -	    sysctl.o capability.o ptrace.o timer.o user.o user_namespace.o \
> +	    sysctl.o capability.o ptrace.o timer.o user.o \
>  	    signal.o sys.o kmod.o workqueue.o pid.o \
>  	    rcupdate.o extable.o params.o posix-timers.o \
>  	    kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \
> @@ -50,6 +49,7 @@ obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
>  obj-$(CONFIG_KPROBES) += kprobes.o
>  obj-$(CONFIG_KGDB) += kgdb.o
>  obj-$(CONFIG_NAMESPACES) += utsname.o
> +obj-$(CONFIG_NAMESPACES_EXPERIMENTAL) += user_namespace.o
>  obj-$(CONFIG_SYSFS) += ksysfs.o
>  obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o
>  obj-$(CONFIG_GENERIC_HARDIRQS) += irq/
> diff --git a/kernel/user.c b/kernel/user.c
> index b45f55f..d7c0831 100644
> --- a/kernel/user.c
> +++ b/kernel/user.c
> @@ -17,6 +17,15 @@
>  #include <linux/module.h>
>  #include <linux/user_namespace.h>
> 
> +struct user_namespace init_user_ns = {
> +	.kref = {
> +		.refcount	= ATOMIC_INIT(2),
> +	},
> +	.root_user = &root_user,
> +};
> +
> +EXPORT_SYMBOL_GPL(init_user_ns);
> +
>  /*
>   * UID task count cache, to get fast user lookup in "alloc_uid"
>   * when changing user ID's (ie setuid() and friends).
> @@ -199,6 +208,7 @@ void switch_uid(struct user_struct *new_
>  	suid_keys(current);
>  }
> 
> +#ifdef CONFIG_NAMESPACES_EXPERIMENTAL
>  void release_uids(struct user_namespace *ns)
>  {
>  	int i;
> @@ -223,6 +233,7 @@ void release_uids(struct user_namespace 
> 
>  	free_uid(ns->root_user);
>  }
> +#endif
> 
>  static int __init uid_cache_init(void)
>  {
> diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c
> index 7af90fc..4c90062 100644
> --- a/kernel/user_namespace.c
> +++ b/kernel/user_namespace.c
> @@ -10,17 +10,6 @@
>  #include <linux/nsproxy.h>
>  #include <linux/user_namespace.h>
> 
> -struct user_namespace init_user_ns = {
> -	.kref = {
> -		.refcount	= ATOMIC_INIT(2),
> -	},
> -	.root_user = &root_user,
> -};
> -
> -EXPORT_SYMBOL_GPL(init_user_ns);
> -
> -#ifdef CONFIG_USER_NS
> -
>  /*
>   * Clone a new ns copying an original user ns, setting refcount to 1
>   * @old_ns: namespace to clone
> @@ -84,5 +73,3 @@ void free_user_ns(struct kref *kref)
>  	release_uids(ns);
>  	kfree(ns);
>  }
> -
> -#endif /* CONFIG_USER_NS */
> 
>