A config option to compile out some namespaces code (v4)

PATCH In review Pavel Emelyanov 2 participants 8 messages Nov 14, 2007

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Pavel Emelyanov

author

2007-11-14 11:26 UTC #0 lore raw

cover A config option to compile out some namespaces code (v4)

Change against v3: rebased on 2.6.24-rc2-mm1

There were some questions like "do I need this on my cellphone" in reply to different namespaces patches. Indeed, the namespaces are not useful for most of the embedded systems, but the code creating and releasing them weights a lot.

So I propose to add a config option which will help embedded people to reduce the vmlinux size. This option simply compiles out the namespaces cloning and releasing code *only*, but keeps all the other logic untouched (e.g. the notion of init_ns).

Moreover, some of the namespaces might be not 100% ready by the time of Linux-2.6.xxx release (like user namespaces or pid namespaces are now). Since each namespace has its own option, which depends on the NAMESPACES, it can be mrked with "depends on EXPERIMENTAL/BROKEN/ANYTHING_ELSE" not to release the functionality that is not 100% ready yet.

When someone tries to clone some namespace with their support turned off, he will receive an EINVAL error.

This patchset can save more than 2KB from the vmlinux when turning the config option "NAMESPACES" to "n".

Signed-off-by Pavel Emelyanov <[email protected]>

Pavel Emelyanov

author

2007-11-14 11:28 UTC #1 lore raw

PATCH 1/6 Add the NAMESPACES config option

The option is selectable if EMBEDDED is chosen only. When the EMBEDDED is off namespaces will be on.

Signed-off-by Pavel Emelyanov <[email protected]>

---

init/Kconfig +9 -0

index 96fba82..4ccc1a0 100644
@@ -404,6 +404,15 @@ config RELAY
 
 	  If unsure, say N.
 
+config NAMESPACES
+	bool "Namespaces support" if EMBEDDED
+	default !EMBEDDED
+	help
+	  Provides the way to make tasks work with different objects using
+	  the same id. For example same IPC id may refer to different objects
+	  or same user id or pid may refer to different tasks when used in
+	  different namespaces.
+
 config BLK_DEV_INITRD
 	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
 	depends on BROKEN || !FRV

Signature · 1 line

1.5.3.4

Pavel Emelyanov

author

2007-11-14 11:30 UTC #2 lore raw

PATCH 2/6 Move the UTS namespace under UTS_NS option

In reply to Pavel Emelyanov

Currently all the namespace management code is in the kernel/utsname.c file, so just compile it out and make stubs in the appropriate header.

The init namespace itself is in init/version.c and is in the kernel all the time.

Signed-off-by Pavel Emelyanov <[email protected]>

---

include/linux/utsname.h +21 -0

index 923db99..1123267 100644
@@ -35,6 +35,7 @@ struct new_utsname {
 #include <linux/sched.h>
 #include <linux/kref.h>
 #include <linux/nsproxy.h>
+#include <linux/err.h>
 #include <asm/atomic.h>
 
 struct uts_namespace {

@@ -43,6 +44,7 @@ struct uts_namespace {
 };
 extern struct uts_namespace init_uts_ns;
 
+#ifdef CONFIG_UTS_NS
 static inline void get_uts_ns(struct uts_namespace *ns)
 {
 	kref_get(&ns->kref);

@@ -56,6 +58,25 @@ static inline void put_uts_ns(struct uts_namespace *ns)
 {
 	kref_put(&ns->kref, free_uts_ns);
 }
+#else
+static inline void get_uts_ns(struct uts_namespace *ns)
+{
+}
+
+static inline void put_uts_ns(struct uts_namespace *ns)
+{
+}
+
+static inline struct uts_namespace *copy_utsname(unsigned long flags,
+					struct uts_namespace *ns)
+{
+	if (flags & CLONE_NEWUTS)
+		return ERR_PTR(-EINVAL);
+
+	return ns;
+}
+#endif
+
 static inline struct new_utsname *utsname(void)
 {
 	return &current->nsproxy->uts_ns->name;

init/Kconfig +7 -0

index 4ccc1a0..2139218 100644
@@ -413,6 +413,13 @@ config NAMESPACES
 	  or same user id or pid may refer to different tasks when used in
 	  different namespaces.
 
+config UTS_NS
+	bool "UTS namespace"
+	depends on NAMESPACES
+	help
+	  In this namespace tasks see different info provided with the
+	  uname() system call
+
 config BLK_DEV_INITRD
 	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
 	depends on BROKEN || !FRV

kernel/Makefile +2 -1

index 876dbcd..19d2411 100644
@@ -9,7 +9,7 @@ obj-y     = sched.o fork.o exec_domain.o panic.o printk.o profile.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 \
 	    hrtimer.o rwsem.o nsproxy.o srcu.o \
-	    utsname.o notifier.o pm_qos_params.o
+	    notifier.o pm_qos_params.o
 
 obj-$(CONFIG_SYSCTL) += sysctl_check.o
 obj-$(CONFIG_STACKTRACE) += stacktrace.o

@@ -48,6 +48,7 @@ obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
 obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
 obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
 obj-$(CONFIG_KPROBES) += kprobes.o
+obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_SYSFS) += ksysfs.o
 obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o
 obj-$(CONFIG_GENERIC_HARDIRQS) += irq/

Signature · 1 line

1.5.3.4

Pavel Emelyanov

author

2007-11-14 11:32 UTC #3 lore raw

PATCH 3/6 Move the IPC namespace under IPC_NS option

In reply to Pavel Emelyanov

Currently the IPC namespace management code is spread over the ipc/*.c files. I moved this code into ipc/namespace.c file which is compiled out when needed.

The linux/ipc_namespace.h file is used to store the prototypes of the functions in namespace.c and the stubs for NAMESPACES=n case. This is done so, because the stub for copy_ipc_namespace requires the knowledge of the CLONE_NEWIPC flag, which is in sched.h. But the linux/ipc.h file itself in included into many many .c files via the sys.h->sem.h sequence so adding the sched.h into it will make all these .c depend on sched.h which is not that good. On the other hand the knowledge about the namespaces stuff is required in 4 .c files only.

Besides, this patch compiles out some auxiliary functions from ipc/sem.c, msg.c and shm.c files. It turned out that moving these functions into namespaces.c is not that easy because they use many other calls and macros from the original file. Moving them would make this patch complicated. On the other hand all these functions can be consolidated, so I will send a separate patch doing this a bit later.

Signed-off-by Pavel Emelyanov <[email protected]>

---

include/linux/ipc.h +0 ~~-52~~

index 408696e..b882610 100644
@@ -100,58 +100,6 @@ struct kern_ipc_perm
 	void		*security;
 };
 
-struct ipc_ids;
-struct ipc_namespace {
-	struct kref	kref;
-	struct ipc_ids	*ids[3];
-
-	int		sem_ctls[4];
-	int		used_sems;
-
-	int		msg_ctlmax;
-	int		msg_ctlmnb;
-	int		msg_ctlmni;
-	atomic_t	msg_bytes;
-	atomic_t	msg_hdrs;
-
-	size_t		shm_ctlmax;
-	size_t		shm_ctlall;
-	int		shm_ctlmni;
-	int		shm_tot;
-};
-
-extern struct ipc_namespace init_ipc_ns;
-
-#ifdef CONFIG_SYSVIPC
-#define INIT_IPC_NS(ns)		.ns		= &init_ipc_ns,
-extern void free_ipc_ns(struct kref *kref);
-extern struct ipc_namespace *copy_ipcs(unsigned long flags,
-						struct ipc_namespace *ns);
-#else
-#define INIT_IPC_NS(ns)
-static inline struct ipc_namespace *copy_ipcs(unsigned long flags,
-						struct ipc_namespace *ns)
-{
-	return ns;
-}
-#endif
-
-static inline struct ipc_namespace *get_ipc_ns(struct ipc_namespace *ns)
-{
-#ifdef CONFIG_SYSVIPC
-	if (ns)
-		kref_get(&ns->kref);
-#endif
-	return ns;
-}
-
-static inline void put_ipc_ns(struct ipc_namespace *ns)
-{
-#ifdef CONFIG_SYSVIPC
-	kref_put(&ns->kref, free_ipc_ns);
-#endif
-}
-
 #endif /* __KERNEL__ */
 
 #endif /* _LINUX_IPC_H */

include/linux/ipc_namespace.h new file +69 -0

69 lines not on this page · raw message

init/Kconfig +7 -0

index 2139218..fe73fe6 100644
@@ -420,6 +420,13 @@ config UTS_NS
 	  In this namespace tasks see different info provided with the
 	  uname() system call
 
+config IPC_NS
+	bool "IPC namespace"
+	depends on NAMESPACES && SYSVIPC
+	help
+	  In this namespace tasks work with IPC ids which correspond to
+	  different IPC objects in different namespaces
+
 config BLK_DEV_INITRD
 	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
 	depends on BROKEN || !FRV

ipc/Makefile +1 -0

index b93bba6..5fc5e33 100644
@@ -7,4 +7,5 @@ obj-$(CONFIG_SYSVIPC) += util.o msgutil.o msg.o sem.o shm.o
 obj-$(CONFIG_SYSVIPC_SYSCTL) += ipc_sysctl.o
 obj_mq-$(CONFIG_COMPAT) += compat_mq.o
 obj-$(CONFIG_POSIX_MQUEUE) += mqueue.o msgutil.o $(obj_mq-y)
+obj-$(CONFIG_IPC_NS) += namespace.o

ipc/ipc_sysctl.c +1 -0

index 79e24e8..7f4235b 100644
@@ -14,6 +14,7 @@
 #include <linux/nsproxy.h>
 #include <linux/sysctl.h>
 #include <linux/uaccess.h>
+#include <linux/ipc_namespace.h>
 
 static void *get_ipc(ctl_table *table)
 {

ipc/msg.c +3 -0

index ec0c724..5879bfe 100644
@@ -36,6 +36,7 @@
 #include <linux/seq_file.h>
 #include <linux/rwsem.h>
 #include <linux/nsproxy.h>
+#include <linux/ipc_namespace.h>
 
 #include <asm/current.h>
 #include <asm/uaccess.h>

@@ -90,6 +91,7 @@ static void __msg_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
 	ipc_init_ids(ids);
 }
 
+#ifdef CONFIG_IPC_NS
 int msg_init_ns(struct ipc_namespace *ns)
 {
 	struct ipc_ids *ids;

@@ -128,6 +130,7 @@ void msg_exit_ns(struct ipc_namespace *ns)
 	kfree(ns->ids[IPC_MSG_IDS]);
 	ns->ids[IPC_MSG_IDS] = NULL;
 }
+#endif
 
 void __init msg_init(void)
 {

ipc/namespace.c new file +73 -0

73 lines not on this page · raw message

ipc/sem.c +3 -0

index d65e285..84c701f 100644
@@ -82,6 +82,7 @@
 #include <linux/seq_file.h>
 #include <linux/rwsem.h>
 #include <linux/nsproxy.h>
+#include <linux/ipc_namespace.h>
 
 #include <asm/uaccess.h>
 #include "util.h"

@@ -128,6 +129,7 @@ static void __sem_init_ns(struct ipc_namespace *ns, struct ipc_ids *ids)
 	ipc_init_ids(ids);
 }
 
+#ifdef CONFIG_IPC_NS
 int sem_init_ns(struct ipc_namespace *ns)
 {
 	struct ipc_ids *ids;

@@ -165,6 +167,7 @@ void sem_exit_ns(struct ipc_namespace *ns)
 	kfree(ns->ids[IPC_SEM_IDS]);
 	ns->ids[IPC_SEM_IDS] = NULL;
 }
+#endif
 
 void __init sem_init (void)
 {

ipc/shm.c +3 -0

index 65c3a29..07f4b7a 100644
@@ -38,6 +38,7 @@
 #include <linux/rwsem.h>
 #include <linux/nsproxy.h>
 #include <linux/mount.h>
+#include <linux/ipc_namespace.h>
 
 #include <asm/uaccess.h>

@@ -96,6 +97,7 @@ static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
 		shm_destroy(ns, shp);
 }
 
+#ifdef CONFIG_IPC_NS
 int shm_init_ns(struct ipc_namespace *ns)
 {
 	struct ipc_ids *ids;

@@ -133,6 +135,7 @@ void shm_exit_ns(struct ipc_namespace *ns)
 	kfree(ns->ids[IPC_SHM_IDS]);
 	ns->ids[IPC_SHM_IDS] = NULL;
 }
+#endif
 
 void __init shm_init (void)
 {

ipc/util.c +1 ~~-60~~

73 lines not on this page · raw message

ipc/util.h +2 -0

index 9ffea40..fc6b729 100644
@@ -20,6 +20,8 @@ void sem_init (void);
 void msg_init (void);
 void shm_init (void);
 
+struct ipc_namespace;
+
 int sem_init_ns(struct ipc_namespace *ns);
 int msg_init_ns(struct ipc_namespace *ns);
 int shm_init_ns(struct ipc_namespace *ns);

kernel/nsproxy.c +1 -0

index 79f871b..f5d332c 100644
@@ -21,6 +21,7 @@
 #include <linux/utsname.h>
 #include <linux/pid_namespace.h>
 #include <net/net_namespace.h>
+#include <linux/ipc_namespace.h>
 
 static struct kmem_cache *nsproxy_cachep;

Signature · 1 line

1.5.3.4

Pavel Emelyanov

author

2007-11-14 11:36 UTC #4 lore raw

PATCH 4/6 Cleanup the code managed with the USER_NS option

In reply to Pavel Emelyanov

Make the user_namespace.o compilation depend on this option and move the init_user_ns into user.c file to make the kernel compile and work without the namespaces support. This make the user namespace code be organized similar to other namespaces'.

Also mask the USER_NS option as "depend on NAMESPACES".

Signed-off-by Pavel Emelyanov <[email protected]>

---

init/Kconfig +8 -9

index fe73fe6..825f10c 100644
@@ -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 PID_NS
 	bool "PID Namespaces (EXPERIMENTAL)"
 	default n

@@ -427,6 +418,14 @@ config IPC_NS
 	  In this namespace tasks work with IPC ids which correspond to
 	  different IPC objects in different namespaces
 
+config USER_NS
+	bool "User namespace (EXPERIMENTAL)"
+	depends on NAMESPACES && EXPERIMENTAL
+	help
+	  This allows containers, i.e. vservers, to use user namespaces
+	  to provide different user info for different servers.
+	  If unsure, say N.
+
 config BLK_DEV_INITRD
 	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
 	depends on BROKEN || !FRV

kernel/Makefile +2 -1

index 19d2411..d01cb7b 100644
@@ -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 \

@@ -49,6 +49,7 @@ obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
 obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
 obj-$(CONFIG_KPROBES) += kprobes.o
 obj-$(CONFIG_UTS_NS) += utsname.o
+obj-$(CONFIG_USER_NS) += user_namespace.o
 obj-$(CONFIG_SYSFS) += ksysfs.o
 obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o
 obj-$(CONFIG_GENERIC_HARDIRQS) += irq/

kernel/user.c +11 -0

index 74a1ddf..624e3d7 100644
@@ -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).

@@ -430,6 +439,7 @@ void switch_uid(struct user_struct *new_user)
 	suid_keys(current);
 }
 
+#ifdef CONFIG_USER_NS
 void release_uids(struct user_namespace *ns)
 {
 	int i;

@@ -454,6 +464,7 @@ void release_uids(struct user_namespace *ns)
 
 	free_uid(ns->root_user);
 }
+#endif
 
 static int __init uid_cache_init(void)
 {

kernel/user_namespace.c +0 ~~-13~~

index 7af90fc..4c90062 100644
@@ -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 */

Signature · 1 line

1.5.3.4

Pavel Emelyanov

author

2007-11-14 11:39 UTC #5 lore raw

PATCH 5/6 Cleanup the code managed with PID_NS option

In reply to Pavel Emelyanov

Just like with the user namespaces, move the namespace management code into the separate .c file and mark the (already existing) PID_NS option as "depend on NAMESPACES"

Signed-off-by Pavel Emelyanov <[email protected]>

---

include/linux/pid.h +1 -1

index e29a900..061abb6 100644
@@ -118,10 +118,10 @@ extern struct pid *find_pid(int nr);
  */
 extern struct pid *find_get_pid(int nr);
 extern struct pid *find_ge_pid(int nr, struct pid_namespace *);
+int next_pidmap(struct pid_namespace *pid_ns, int last);
 
 extern struct pid *alloc_pid(struct pid_namespace *ns);
 extern void FASTCALL(free_pid(struct pid *pid));
-extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
 
 /*
  * the helpers to get the pid's id seen from different namespaces

include/linux/pid_namespace.h +6 -0

index 1689e28..fcd61fa 100644
@@ -39,6 +39,7 @@ static inline struct pid_namespace *get_pid_ns(struct pid_namespace *ns)
 
 extern struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *ns);
 extern void free_pid_ns(struct kref *kref);
+extern void zap_pid_ns_processes(struct pid_namespace *pid_ns);
 
 static inline void put_pid_ns(struct pid_namespace *ns)
 {

@@ -66,6 +67,11 @@ static inline void put_pid_ns(struct pid_namespace *ns)
 {
 }
 
+
+static inline void zap_pid_ns_processes(struct pid_namespace *ns)
+{
+	BUG();
+}
 #endif /* CONFIG_PID_NS */
 
 static inline struct pid_namespace *task_active_pid_ns(struct task_struct *tsk)

init/Kconfig +12 ~~-12~~

index 825f10c..f21bc4d 100644
@@ -206,18 +206,6 @@ config TASK_IO_ACCOUNTING
 
 	  Say N if unsure.
 
-config PID_NS
-	bool "PID Namespaces (EXPERIMENTAL)"
-	default n
-	depends on EXPERIMENTAL
-	help
-	  Suport process id namespaces.  This allows having multiple
-	  process with the same pid as long as they are in different
-	  pid namespaces.  This is a building block of containers.
-
-	  Unless you want to work with an experimental feature
-	  say N here.
-
 config AUDIT
 	bool "Auditing support"
 	depends on NET

@@ -426,6 +414,18 @@ config USER_NS
 	  to provide different user info for different servers.
 	  If unsure, say N.
 
+config PID_NS
+	bool "PID Namespaces (EXPERIMENTAL)"
+	default n
+	depends on NAMESPACES && EXPERIMENTAL
+	help
+	  Suport process id namespaces.  This allows having multiple
+	  process with the same pid as long as they are in different
+	  pid namespaces.  This is a building block of containers.
+
+	  Unless you want to work with an experimental feature
+	  say N here.
+
 config BLK_DEV_INITRD
 	bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
 	depends on BROKEN || !FRV

kernel/Makefile +1 -0

index d01cb7b..d108027 100644
@@ -50,6 +50,7 @@ obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
 obj-$(CONFIG_KPROBES) += kprobes.o
 obj-$(CONFIG_UTS_NS) += utsname.o
 obj-$(CONFIG_USER_NS) += user_namespace.o
+obj-$(CONFIG_PID_NS) += pid_namespace.o
 obj-$(CONFIG_SYSFS) += ksysfs.o
 obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o
 obj-$(CONFIG_GENERIC_HARDIRQS) += irq/

kernel/pid.c +3 ~~-181~~

206 lines not on this page · raw message

kernel/pid_namespace.c new file +197 -0

197 lines not on this page · raw message

Pavel Emelyanov

author

2007-11-14 11:41 UTC #6 lore raw

PATCH 6/6 Mark NET_NS with "depends on NAMESPACES"

In reply to Pavel Emelyanov

There's already an option controlling the net namespaces cloning code, so make it work the same way as all the other namespaces' options.

Should I wait till the option itself gets to mainline and resend this patch to David?

Signed-off-by Pavel Emelyanov <[email protected]>

---

net/Kconfig +1 -1

index ab4e6da..d61a025 100644
@@ -30,7 +30,7 @@ menu "Networking options"
 config NET_NS
 	bool "Network namespace support"
 	default n
-	depends on EXPERIMENTAL && !SYSFS
+	depends on EXPERIMENTAL && !SYSFS && NAMESPACES
 	help
 	  Allow user space to create what appear to be multiple instances
 	  of the network stack.

Serge E. Hallyn

Acked-by on the v1 series

2007-11-14 14:58 UTC #7 lore raw

In reply to Pavel Emelyanov

Quoted 19 lines · Pavel Emelyanov

Change against v3: rebased on 2.6.24-rc2-mm1
There were some questions like "do I need this on my cellphone" in reply to different namespaces patches. Indeed, the namespaces are not useful for most of the embedded systems, but the code creating and releasing them weights a lot.
So I propose to add a config option which will help embedded people to reduce the vmlinux size. This option simply compiles out the namespaces cloning and releasing code *only*, but keeps all the other logic untouched (e.g. the notion of init_ns).
Moreover, some of the namespaces might be not 100% ready by the time of Linux-2.6.xxx release (like user namespaces or pid namespaces are now). Since each namespace has its own option, which depends on the NAMESPACES, it can be mrked with "depends on EXPERIMENTAL/BROKEN/ANYTHING_ELSE" not to release the functionality that is not 100% ready yet.

Quoted 7 lines

When someone tries to clone some namespace with their support turned off, he will receive an EINVAL error.
This patchset can save more than 2KB from the vmlinux when turning the config option "NAMESPACES" to "n".
Signed-off-by Pavel Emelyanov <[email protected]>

Pretty sure I did this a few versions ago, but

Acked-by Serge Hallyn <[email protected]>

for the whole set.

thanks,
-serge