[PATCH] kobject_uevent CONFIG_SYSFS=n build fix

[PATCH] kobject_uevent CONFIG_SYSFS=n build fix

[Jun'ichi Nomura]

[-- Attachment #1: Type: text/plain, Size: 1224 bytes --]

Hello,

In 2.6.16-rc6 (probably in earlier rc as well),
following build error occurs with CONFIG_SYSFS=n.

kernel/built-in.o(.data+0x1d40): undefined reference to `uevent_helper'
lib/lib.a(kobject_uevent.o)(.text+0x5c1): In function `kobject_uevent':
/build/rc6/source/lib/kobject_uevent.c:152: undefined reference to `uevent_seqnum'
lib/lib.a(kobject_uevent.o)(.text+0x5d0):/build/rc6/source/lib/kobject_uevent.c:152: undefined reference to `uevent_seqnum'
lib/lib.a(kobject_uevent.o)(.text+0x901):/build/rc6/source/lib/kobject_uevent.c:182: undefined reference to `uevent_helper'
lib/lib.a(kobject_uevent.o)(.text+0x910):/build/rc6/source/lib/kobject_uevent.c:182: undefined reference to `uevent_helper'

This seems to be caused by mismatch of build condition.
uevent_seqnum and uevent_helper are conditional to CONFIG_SYSFS.
While they are referenced if CONFIG_HOTPLUG (and CONFIG_NET) is enabled.

Attached patch consolidates them to CONFIG_HOTPLUG && CONFIG_NET.

I tried with (!CONFIG_NET && CONFIG_SYSFS) and
(CONFIG_NET && !CONFIG_SYSFS).
Both built ok.
So I think it doesn't conflict with "[PATCH] kobject_uevent CONFIG_NET=n
fix" which is in 2.6.16-rc6.

Thanks,
-- 
Jun'ichi Nomura, NEC Solutions (America), Inc.

[-- Attachment #2: nosysfs-build.patch --]
[-- Type: text/x-patch, Size: 3279 bytes --]

CONFIG_SYSFS=n fails to build due to mismatch of conditions
for uevent_seqnum and uevent_helper.

kernel/built-in.o(.data+0x1d40): undefined reference to `uevent_helper'
lib/lib.a(kobject_uevent.o)(.text+0x5c1): In function `kobject_uevent':
/build/rc6/source/lib/kobject_uevent.c:152: undefined reference to `uevent_seqnum'
lib/lib.a(kobject_uevent.o)(.text+0x5d0):/build/rc6/source/lib/kobject_uevent.c:152: undefined reference to `uevent_seqnum'
lib/lib.a(kobject_uevent.o)(.text+0x901):/build/rc6/source/lib/kobject_uevent.c:182: undefined reference to `uevent_helper'
lib/lib.a(kobject_uevent.o)(.text+0x910):/build/rc6/source/lib/kobject_uevent.c:182: undefined reference to `uevent_helper'

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>


--- linux-2.6.16-rc6.orig/lib/kobject_uevent.c	2006-03-14 08:57:23.000000000 -0500
+++ linux-2.6.16-rc6/lib/kobject_uevent.c	2006-03-14 08:52:57.000000000 -0500
@@ -26,6 +26,9 @@
 #define NUM_ENVP	32	/* number of env pointers */
 
 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
+u64 uevent_seqnum;
+char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
+
 static DEFINE_SPINLOCK(sequence_lock);
 static struct sock *uevent_sock;
 
--- linux-2.6.16-rc6.orig/kernel/sysctl.c	2006-03-14 09:17:09.000000000 -0500
+++ linux-2.6.16-rc6/kernel/sysctl.c	2006-03-14 09:24:32.000000000 -0500
@@ -399,7 +399,7 @@ static ctl_table kern_table[] = {
 		.strategy	= &sysctl_string,
 	},
 #endif
-#ifdef CONFIG_HOTPLUG
+#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 	{
 		.ctl_name	= KERN_HOTPLUG,
 		.procname	= "hotplug",
--- linux-2.6.16-rc6.orig/kernel/ksysfs.c	2006-03-14 08:57:31.000000000 -0500
+++ linux-2.6.16-rc6/kernel/ksysfs.c	2006-03-14 09:38:44.000000000 -0500
@@ -15,9 +15,6 @@
 #include <linux/module.h>
 #include <linux/init.h>
 
-u64 uevent_seqnum;
-char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
-
 #define KERNEL_ATTR_RO(_name) \
 static struct subsys_attribute _name##_attr = __ATTR_RO(_name)
 
@@ -25,7 +22,7 @@ static struct subsys_attribute _name##_a
 static struct subsys_attribute _name##_attr = \
 	__ATTR(_name, 0644, _name##_show, _name##_store)
 
-#ifdef CONFIG_HOTPLUG
+#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 /* current uevent sequence number */
 static ssize_t uevent_seqnum_show(struct subsystem *subsys, char *page)
 {
@@ -55,7 +52,7 @@ decl_subsys(kernel, NULL, NULL);
 EXPORT_SYMBOL_GPL(kernel_subsys);
 
 static struct attribute * kernel_attrs[] = {
-#ifdef CONFIG_HOTPLUG
+#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 	&uevent_seqnum_attr.attr,
 	&uevent_helper_attr.attr,
 #endif
--- linux-2.6.16-rc6.orig/include/linux/kobject.h	2006-03-14 10:00:20.000000000 -0500
+++ linux-2.6.16-rc6/include/linux/kobject.h	2006-03-14 09:59:52.000000000 -0500
@@ -27,6 +27,8 @@
 #include <asm/atomic.h>
 
 #define KOBJ_NAME_LEN			20
+
+#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 #define UEVENT_HELPER_PATH_LEN		256
 
 /* path to the userspace helper executed on an event */
@@ -34,6 +36,7 @@ extern char uevent_helper[];
 
 /* counter to tag the uevent, read only except for the kobject core */
 extern u64 uevent_seqnum;
+#endif
 
 /* the actions here must match the proper string in lib/kobject_uevent.c */
 typedef int __bitwise kobject_action_t;

Re: [PATCH] kobject_uevent CONFIG_SYSFS=n build fix

[Greg KH]

On Tue, Mar 14, 2006 at 11:11:00AM -0500, Jun'ichi Nomura wrote:
> Hello,
> 
> In 2.6.16-rc6 (probably in earlier rc as well),
> following build error occurs with CONFIG_SYSFS=n.
> 
> kernel/built-in.o(.data+0x1d40): undefined reference to `uevent_helper'
> lib/lib.a(kobject_uevent.o)(.text+0x5c1): In function `kobject_uevent':
> /build/rc6/source/lib/kobject_uevent.c:152: undefined reference to `uevent_seqnum'
> lib/lib.a(kobject_uevent.o)(.text+0x5d0):/build/rc6/source/lib/kobject_uevent.c:152: undefined reference to `uevent_seqnum'
> lib/lib.a(kobject_uevent.o)(.text+0x901):/build/rc6/source/lib/kobject_uevent.c:182: undefined reference to `uevent_helper'
> lib/lib.a(kobject_uevent.o)(.text+0x910):/build/rc6/source/lib/kobject_uevent.c:182: undefined reference to `uevent_helper'
> 
> This seems to be caused by mismatch of build condition.
> uevent_seqnum and uevent_helper are conditional to CONFIG_SYSFS.
> While they are referenced if CONFIG_HOTPLUG (and CONFIG_NET) is enabled.
> 
> Attached patch consolidates them to CONFIG_HOTPLUG && CONFIG_NET.
> 
> I tried with (!CONFIG_NET && CONFIG_SYSFS) and
> (CONFIG_NET && !CONFIG_SYSFS).
> Both built ok.
> So I think it doesn't conflict with "[PATCH] kobject_uevent CONFIG_NET=n
> fix" which is in 2.6.16-rc6.
> 
> Thanks,
> -- 
> Jun'ichi Nomura, NEC Solutions (America), Inc.

> CONFIG_SYSFS=n fails to build due to mismatch of conditions
> for uevent_seqnum and uevent_helper.
> 
> kernel/built-in.o(.data+0x1d40): undefined reference to `uevent_helper'
> lib/lib.a(kobject_uevent.o)(.text+0x5c1): In function `kobject_uevent':
> /build/rc6/source/lib/kobject_uevent.c:152: undefined reference to `uevent_seqnum'
> lib/lib.a(kobject_uevent.o)(.text+0x5d0):/build/rc6/source/lib/kobject_uevent.c:152: undefined reference to `uevent_seqnum'
> lib/lib.a(kobject_uevent.o)(.text+0x901):/build/rc6/source/lib/kobject_uevent.c:182: undefined reference to `uevent_helper'
> lib/lib.a(kobject_uevent.o)(.text+0x910):/build/rc6/source/lib/kobject_uevent.c:182: undefined reference to `uevent_helper'
> 
> Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
> 
> 
> --- linux-2.6.16-rc6.orig/lib/kobject_uevent.c	2006-03-14 08:57:23.000000000 -0500
> +++ linux-2.6.16-rc6/lib/kobject_uevent.c	2006-03-14 08:52:57.000000000 -0500
> @@ -26,6 +26,9 @@
>  #define NUM_ENVP	32	/* number of env pointers */
>  
>  #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
> +u64 uevent_seqnum;
> +char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";

No, the seqnum and helper can be called even if we have not defined
CONFIG_NET.  Please redo the patch based on this.

thanks,

greg k-h

Re: [PATCH] kobject_uevent CONFIG_SYSFS=n build fix

[Jun'ichi Nomura]

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Hi Greg,

Greg KH wrote:
>> #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
>>+u64 uevent_seqnum;
>>+char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
> 
> No, the seqnum and helper can be called even if we have not defined
> CONFIG_NET.  Please redo the patch based on this.

OK, thanks for the comment.
I thought it could be conditional on CONFIG_NET because
it's used only from kobject_uevent() except for
kernel/ksysfs.c which just exports them to sysfs.
Are there other users? Or do you mean we have to keep
sysfs files for user space?

Attached patch makes them conditional on CONFIG_HOTPLUG only.
Build tested with both (!CONFIG_NET && CONFIG_SYSFS) and
(CONFIG_NET && !CONFIG_SYSFS).
Does this look correct?

Thanks,
-- 
Jun'ichi Nomura, NEC Solutions (America), Inc.

[-- Attachment #2: kobject_uevent-config_sysfs_n-build-fix.patch --]
[-- Type: text/x-patch, Size: 1599 bytes --]

--- linux-2.6.16-rc6-mm1.orig/lib/kobject_uevent.c	2006-03-14 22:57:23.000000000 +0900
+++ linux-2.6.16-rc6-mm1/lib/kobject_uevent.c	2006-03-15 08:39:33.000000000 +0900
@@ -25,6 +25,11 @@
 #define BUFFER_SIZE	2048	/* buffer for the variables */
 #define NUM_ENVP	32	/* number of env pointers */
 
+#ifdef CONFIG_HOTPLUG
+u64 uevent_seqnum;
+char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
+#endif
+
 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 static DEFINE_SPINLOCK(sequence_lock);
 static struct sock *uevent_sock;
--- linux-2.6.16-rc6-mm1.orig/kernel/ksysfs.c	2006-03-14 22:57:31.000000000 +0900
+++ linux-2.6.16-rc6-mm1/kernel/ksysfs.c	2006-03-15 08:41:11.000000000 +0900
@@ -15,9 +15,6 @@
 #include <linux/module.h>
 #include <linux/init.h>
 
-u64 uevent_seqnum;
-char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
-
 #define KERNEL_ATTR_RO(_name) \
 static struct subsys_attribute _name##_attr = __ATTR_RO(_name)
 
--- linux-2.6.16-rc6-mm1.orig/include/linux/kobject.h	2006-03-15 00:00:20.000000000 +0900
+++ linux-2.6.16-rc6-mm1/include/linux/kobject.h	2006-03-15 08:38:45.000000000 +0900
@@ -27,6 +27,8 @@
 #include <asm/atomic.h>
 
 #define KOBJ_NAME_LEN			20
+
+#ifdef CONFIG_HOTPLUG
 #define UEVENT_HELPER_PATH_LEN		256
 
 /* path to the userspace helper executed on an event */
@@ -34,6 +36,7 @@ extern char uevent_helper[];
 
 /* counter to tag the uevent, read only except for the kobject core */
 extern u64 uevent_seqnum;
+#endif
 
 /* the actions here must match the proper string in lib/kobject_uevent.c */
 typedef int __bitwise kobject_action_t;

Re: [PATCH] kobject_uevent CONFIG_SYSFS=n build fix

[Greg KH]

On Tue, Mar 14, 2006 at 07:00:17PM -0500, Jun'ichi Nomura wrote:
> --- linux-2.6.16-rc6-mm1.orig/lib/kobject_uevent.c	2006-03-14 22:57:23.000000000 +0900
> +++ linux-2.6.16-rc6-mm1/lib/kobject_uevent.c	2006-03-15 08:39:33.000000000 +0900
> @@ -25,6 +25,11 @@
>  #define BUFFER_SIZE	2048	/* buffer for the variables */
>  #define NUM_ENVP	32	/* number of env pointers */
>  
> +#ifdef CONFIG_HOTPLUG
> +u64 uevent_seqnum;
> +char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
> +#endif
> +
>  #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
>  static DEFINE_SPINLOCK(sequence_lock);
>  static struct sock *uevent_sock;
> --- linux-2.6.16-rc6-mm1.orig/kernel/ksysfs.c	2006-03-14 22:57:31.000000000 +0900
> +++ linux-2.6.16-rc6-mm1/kernel/ksysfs.c	2006-03-15 08:41:11.000000000 +0900
> @@ -15,9 +15,6 @@
>  #include <linux/module.h>
>  #include <linux/init.h>
>  
> -u64 uevent_seqnum;
> -char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
> -
>  #define KERNEL_ATTR_RO(_name) \
>  static struct subsys_attribute _name##_attr = __ATTR_RO(_name)
>  

Those two changes look correct.  But why did you modify kobject.h below?

> --- linux-2.6.16-rc6-mm1.orig/include/linux/kobject.h	2006-03-15 00:00:20.000000000 +0900
> +++ linux-2.6.16-rc6-mm1/include/linux/kobject.h	2006-03-15 08:38:45.000000000 +0900
> @@ -27,6 +27,8 @@
>  #include <asm/atomic.h>
>  
>  #define KOBJ_NAME_LEN			20
> +
> +#ifdef CONFIG_HOTPLUG
>  #define UEVENT_HELPER_PATH_LEN		256
>  
>  /* path to the userspace helper executed on an event */
> @@ -34,6 +36,7 @@ extern char uevent_helper[];
>  
>  /* counter to tag the uevent, read only except for the kobject core */
>  extern u64 uevent_seqnum;
> +#endif
>  
>  /* the actions here must match the proper string in lib/kobject_uevent.c */
>  typedef int __bitwise kobject_action_t;

That shouldn't be needed, right?

thanks,

greg k-h

Re: [PATCH] kobject_uevent CONFIG_SYSFS=n build fix

[Jun'ichi Nomura]

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Hi,

Greg KH wrote:
>>@@ -27,6 +27,8 @@
>> #include <asm/atomic.h>
>> 
>> #define KOBJ_NAME_LEN			20
>>+
>>+#ifdef CONFIG_HOTPLUG
>> #define UEVENT_HELPER_PATH_LEN		256

> That shouldn't be needed, right?

You're right. They are not needed.
Please disregard that part.

Thanks,
-- 
Jun'ichi Nomura, NEC Solutions (America), Inc.

[-- Attachment #2: kobject_uevent-config_sysfs_n-build-fix.patch --]
[-- Type: text/x-patch, Size: 952 bytes --]

--- linux-2.6.16-rc6-mm1.orig/lib/kobject_uevent.c	2006-03-14 22:57:23.000000000 +0900
+++ linux-2.6.16-rc6-mm1/lib/kobject_uevent.c	2006-03-15 08:39:33.000000000 +0900
@@ -25,6 +25,11 @@
 #define BUFFER_SIZE	2048	/* buffer for the variables */
 #define NUM_ENVP	32	/* number of env pointers */
 
+#ifdef CONFIG_HOTPLUG
+u64 uevent_seqnum;
+char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
+#endif
+
 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 static DEFINE_SPINLOCK(sequence_lock);
 static struct sock *uevent_sock;
--- linux-2.6.16-rc6-mm1.orig/kernel/ksysfs.c	2006-03-14 22:57:31.000000000 +0900
+++ linux-2.6.16-rc6-mm1/kernel/ksysfs.c	2006-03-15 08:41:11.000000000 +0900
@@ -15,9 +15,6 @@
 #include <linux/module.h>
 #include <linux/init.h>
 
-u64 uevent_seqnum;
-char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
-
 #define KERNEL_ATTR_RO(_name) \
 static struct subsys_attribute _name##_attr = __ATTR_RO(_name)

Re: [PATCH] kobject_uevent CONFIG_SYSFS=n build fix

[Greg KH]

On Tue, Mar 14, 2006 at 08:03:39PM -0500, Jun'ichi Nomura wrote:
> Hi,
> 
> Greg KH wrote:
> >>@@ -27,6 +27,8 @@
> >>#include <asm/atomic.h>
> >>
> >>#define KOBJ_NAME_LEN			20
> >>+
> >>+#ifdef CONFIG_HOTPLUG
> >>#define UEVENT_HELPER_PATH_LEN		256
> 
> >That shouldn't be needed, right?
> 
> You're right. They are not needed.
> Please disregard that part.

Looks good.  Care to resend it one more time, this time with a good
changelog description and a Signed-off-by: line?

thanks,

greg k-h

Re: [PATCH] kobject_uevent CONFIG_SYSFS=n build fix

[Jun'ichi Nomura]

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Greg KH wrote:
>>>>+#ifdef CONFIG_HOTPLUG
>>>>#define UEVENT_HELPER_PATH_LEN		256
>>
>>>That shouldn't be needed, right?
>>
>>You're right. They are not needed.
>>Please disregard that part.
> 
> 
> Looks good.  Care to resend it one more time, this time with a good
> changelog description and a Signed-off-by: line?

OK, here you are.
The patch is applicable to either 2.6.16-rc6 or 2.6.16-rc6-mm1.

Thanks,
-- 
Jun'ichi Nomura, NEC Solutions (America), Inc.

[-- Attachment #2: kobject_uevent-config_sysfs_n-build-fix.patch --]
[-- Type: text/x-patch, Size: 1169 bytes --]

Moving uevent_seqnum and uevent_helper to kobject_uevent.c
because they are used even if CONFIG_SYSFS=n
while kernel/ksysfs.c is built only if CONFIG_SYSFS=y,

Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>

--- linux-2.6.16-rc6-mm1.orig/lib/kobject_uevent.c	2006-03-14 22:57:23.000000000 +0900
+++ linux-2.6.16-rc6-mm1/lib/kobject_uevent.c	2006-03-15 08:39:33.000000000 +0900
@@ -25,6 +25,11 @@
 #define BUFFER_SIZE	2048	/* buffer for the variables */
 #define NUM_ENVP	32	/* number of env pointers */
 
+#ifdef CONFIG_HOTPLUG
+u64 uevent_seqnum;
+char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
+#endif
+
 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 static DEFINE_SPINLOCK(sequence_lock);
 static struct sock *uevent_sock;
--- linux-2.6.16-rc6-mm1.orig/kernel/ksysfs.c	2006-03-14 22:57:31.000000000 +0900
+++ linux-2.6.16-rc6-mm1/kernel/ksysfs.c	2006-03-15 08:41:11.000000000 +0900
@@ -15,9 +15,6 @@
 #include <linux/module.h>
 #include <linux/init.h>
 
-u64 uevent_seqnum;
-char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug";
-
 #define KERNEL_ATTR_RO(_name) \
 static struct subsys_attribute _name##_attr = __ATTR_RO(_name)