[BUG] module-init-tools

[BUG] module-init-tools

[Ustyugov Roman]

Hello!

I found a bug in module-init-tools.

'lsmod' shows a wrong module name, when module name complied with some 
"define" at one of kernel header files.

For example,

File "current.c"
=======================
#include <linux/kernel.h>
#include <linux/module.h>

int init_module(void) {

    return 0;
}

void cleanup_module() {
}

MODULE_LICENSE("GPL");
=======================

Makefile:

=======================
obj-m   += current.o
=======================

Make this module and type commands:

insmod current.ko
lsmod

And we can see:

Module                  Size  Used by
get_current()           1152  0             <---- Oops,  must be 'current'
smbfs                  61432  2
hfsplus                56708  0
nls_cp866               5120  1
nls_iso8859_1           4096  0
nls_cp437               5760  0
vfat                   12800  0
fat                    37916  1 vfat
nls_utf8                2048  1
           .....

File <asm/current.h>: 

===================
          ...
#define    current    get_current()
          ...
===================

Try to remove module:

romanu:/current # rmmod current
ERROR: Module current does not exist in /proc/modules
romanu:/current # rmmod -v "get_current()"
rmmod get_current(), wait=no
romanu:/current # 

I can't remove module with 'rmmod current', 
but can with 
        rmmod "get_current()"

Is it a bug?

Then, next example.

File 'init_stack.c'
=================
#include <linux/kernel.h>
#include <linux/module.h>

int init_module(void) {

    return 0;
}

void cleanup_module() {
}

MODULE_LICENSE("GPL");
=================

Make and insert module 'init_stack.ko':

lsmod:

Module                  Size  Used by
get_current()           1152  0
(init_thread_union.stack)     1152  0    <---- Oops,  must be 'init_stack'
smbfs                  61432  2
hfsplus                56708  0
nls_cp866               5120  1
nls_iso8859_1           4096  0

Now I can't to remove it at all ! :(:(

>From <asm/thread_info.h>

====================
        ...
#define init_stack              (init_thread_union.stack)
        ...
====================

Some information about software:

OS: SuSE Pro 9.3
kernel version:  2.6.11.4-21.8-default
module-init-tools version: 3.2_pre1-7

--
WBR, Roman.

Re: [BUG] module-init-tools

[Coywolf Qi Hunt]

On 9/19/05, Ustyugov Roman <dr_unique@ymg.ru> wrote:
> Hello!
> 
> I found a bug in module-init-tools.
> 
> 'lsmod' shows a wrong module name, when module name complied with some
> "define" at one of kernel header files.
> 
> For example,
> 
> File "current.c"
> =======================
> #include <linux/kernel.h>
> #include <linux/module.h>
> 
> int init_module(void) {
> 
>   return 0;
> }
> 
> void cleanup_module() {
> }
> 
> MODULE_LICENSE("GPL");
> =======================
> 
> Makefile:
> 
> =======================
> obj-m += current.o
> =======================
> 
> Make this module and type commands:
> 
> insmod current.ko
> lsmod
> 
> And we can see:
> 
> Module Size Used by
> get_current() 1152 0 <---- Oops, must be 'current'
> smbfs 61432 2
> hfsplus 56708 0
> nls_cp866 5120 1
> nls_iso8859_1 4096 0
> nls_cp437 5760 0
> vfat 12800 0
> fat 37916 1 vfat
> nls_utf8 2048 1
>   .....
> 
> File <asm/current.h>:
> 
> ===================
>   ...
> #define current get_current()
>   ...
> ===================
> 
> Try to remove module:
> 
> romanu:/current # rmmod current
> ERROR: Module current does not exist in /proc/modules
> romanu:/current # rmmod -v "get_current()"
> rmmod get_current(), wait=no
> romanu:/current #
> 
> I can't remove module with 'rmmod current',
> but can with
> rmmod "get_current()"
> 
> Is it a bug?

Yes, it's a bug. But it's a bad idea too to use well known kernel
symbols as module names.
-- 
Coywolf Qi Hunt
http://sosdg.org/~coywolf/

Re: [BUG] module-init-tools

[Ustyugov Roman]

On 9/19/05 Coywolf Qi Hunt wrote:
> Yes, it's a bug. But it's a bad idea too to use well known kernel
> symbols as module names.

Sure. Please, add to module documentation:

To make unique name of module use command:

	touch `cat /dev/urandom | uuencode -m - | head -n 2 | tail -c10`.c

;-)

-- 
RomanU

Re: [BUG] module-init-tools

[Coywolf Qi Hunt]

On 9/19/05, Ustyugov Roman <dr_unique@ymg.ru> wrote:
> Hello!
> 
> I found a bug in module-init-tools.
> 
> 'lsmod' shows a wrong module name, when module name complied with some
> "define" at one of kernel header files.
> 
> For example,
> 
> File "current.c"
> =======================
> #include <linux/kernel.h>
> #include <linux/module.h>
> 
> int init_module(void) {
> 
>   return 0;
> }
> 
> void cleanup_module() {
> }
> 
> MODULE_LICENSE("GPL");
> =======================
> 
> Makefile:
> 
> =======================
> obj-m += current.o
> =======================
> 
> Make this module and type commands:
> 
> insmod current.ko
> lsmod
> 
> And we can see:
> 
> Module Size Used by
> get_current() 1152 0 <---- Oops, must be 'current'
> smbfs 61432 2
> hfsplus 56708 0
> nls_cp866 5120 1
> nls_iso8859_1 4096 0
> nls_cp437 5760 0
> vfat 12800 0
> fat 37916 1 vfat
> nls_utf8 2048 1
>   .....
> 
> File <asm/current.h>:
> 
> ===================
>   ...
> #define current get_current()
>   ...
> ===================
> 
> Try to remove module:
> 
> romanu:/current # rmmod current
> ERROR: Module current does not exist in /proc/modules
> romanu:/current # rmmod -v "get_current()"
> rmmod get_current(), wait=no
> romanu:/current #
> 
> I can't remove module with 'rmmod current',
> but can with
> rmmod "get_current()"
> 
> Is it a bug?
> 
> Then, next example.
> 
> File 'init_stack.c'
> =================
> #include <linux/kernel.h>
> #include <linux/module.h>
> 
> int init_module(void) {
> 
>   return 0;
> }
> 
> void cleanup_module() {
> }
> 
> MODULE_LICENSE("GPL");
> =================
> 
> Make and insert module 'init_stack.ko':
> 
> lsmod:
> 
> Module Size Used by
> get_current() 1152 0
> (init_thread_union.stack) 1152 0 <---- Oops, must be 'init_stack'
> smbfs 61432 2
> hfsplus 56708 0
> nls_cp866 5120 1
> nls_iso8859_1 4096 0
> 
> Now I can't to remove it at all ! :(:(
> 
> From <asm/thread_info.h>
> 
> ====================
> ...
> #define init_stack (init_thread_union.stack)
> ...
> ====================
> 
> Some information about software:
> 
> OS: SuSE Pro 9.3
> kernel version: 2.6.11.4-21.8-default
> module-init-tools version: 3.2_pre1-7

Actually, this is a kbuild bug, not module-init-tools' fault. 

(cc Sam)

-- 
Coywolf Qi Hunt
http://sosdg.org/~coywolf/

Re: [BUG] module-init-tools

[Ustyugov Roman]

Thayumanavar Sachithanantham wrote:
> > buf_printf(b, " .name = __stringify(KBUILD_MODNAME),\n");
>
> $(modname))),-DKBUILD_MODNAME=$(subst $(comma),_,$(subst -,_,$(modname))))
>

In my case I've already had these lines at files you're specified.
But situation is unchanged. Module name is wrong :(
Any ideas?

-- 
RomanU

Re: [BUG] module-init-tools

[Thayumanavar Sachithanantham]

Please change the lines that you have mentioned to this:
 
buf_printf(b, " .name = KBUILD_MODNAME,\n"); 
modname_flags = $(if $(filter 1,$(words $(modname))),-D'DUM(a)=\#a'
-D'KBUILD_MODNAME=DUM($(subst $(comma),_,$(subst -,_,$(modname))))')
 
Let me know your results.Take care of the quotes while you change.

Thayumanavar

Re: [BUG] kbuild

[Ustyugov Roman]

Thayumanavar Sachithanantham wrote:
> Let me know your results.Take care of the quotes while you change.

make -C ../../../linux-2.6.11.4-21.8
 O=../linux-2.6.11.4-21.8-obj/i386/default /bin/sh: -c: line 0: syntax error
 near unexpected token `('
/bin/sh: -c: line 0: `set -e;
.....

What symbol must be between
-D'DUM(a)=\#a'
and
-D'KBUILD_MODNAME=DUM($(subst $(comma),_,$(subst -,_,$(modname))))')

?

I tried a space, comma and no spaces, also with quotes and without any, but
got an error above.

Here is my line:
modname_flags  = $(if $(filter 1,$(words $(modname))),-D'DUM(a)=\#a'
-D'KBUILD_MODNAME=DUM($(subst $(comma),_,$(subst -,_,$(modname))))')

-- 
RomanU

Re: [BUG] kbuild

[Thayumanavar Sachithanantham]

On 9/20/05, Ustyugov Roman <dr_unique@ymg.ru> wrote:
> Thayumanavar Sachithanantham wrote:
> > Let me know your results.Take care of the quotes while you change.
> 
> make -C ../../../linux-2.6.11.4-21.8
>  O=../linux-2.6.11.4-21.8-obj/i386/default /bin/sh: -c: line 0: syntax error
>  near unexpected token `('
> /bin/sh: -c: line 0: `set -e;
> .....
> 
> What symbol must be between
> -D'DUM(a)=\#a'
> and
> -D'KBUILD_MODNAME=DUM($(subst $(comma),_,$(subst -,_,$(modname))))')
> 
> ?
> 
> I tried a space, comma and no spaces, also with quotes and without any, but
> got an error above.
> 
> Here is my line:
> modname_flags  = $(if $(filter 1,$(words $(modname))),-D'DUM(a)=\#a'
> -D'KBUILD_MODNAME=DUM($(subst $(comma),_,$(subst -,_,$(modname))))')
> 
> --
> RomanU
> 

A space.
Let me know if you still get errors. Also there should be an extra
parantheses before the quote.

Thayumanavar S.

[PATCH] kbuild: using well known kernel symbols as module names.

[Ustyugov Roman]

Here is a Thayumanavar's (thayumk@gmail.com) patch with small changes.  I have 
to use double quotes, but not single ones.
Problem was solved.

--- linux/scripts/Makefile.lib.orig	2005-03-02 10:38:09.000000000 +0300
+++ linux/scripts/Makefile.lib	2005-09-20 13:14:13.000000000 +0400
@@ -96,7 +96,7 @@ depfile = $(subst $(comma),_,$(@D)/.$(@F
 #       than one module. In that case KBUILD_MODNAME will be set to foo_bar,
 #       where foo and bar are the name of the modules.
 basename_flags = -DKBUILD_BASENAME=$(subst $(comma),_,$(subst -,_,$(*F)))
-modname_flags  = $(if $(filter 1,$(words 
$(modname))),-DKBUILD_MODNAME=$(subst $(comma),_,$(subst -,_,$(modname))))
+modname_flags  = $(if $(filter 1,$(words $(modname))),-D"DUM(a)=\#a" 
-D"KBUILD_MODNAME=DUM($(subst $(comma),_,$(subst -,_,$(modname))))")
 
 _c_flags       = $(CFLAGS) $(EXTRA_CFLAGS) $(CFLAGS_$(*F).o)
 _a_flags       = $(AFLAGS) $(EXTRA_AFLAGS) $(AFLAGS_$(*F).o)
--- linux/scripts/mod/modpost.c.orig	2005-07-23 04:41:06.000000000 +0400
+++ linux/scripts/mod/modpost.c	2005-09-20 13:19:21.000000000 +0400
@@ -575,7 +575,7 @@ add_header(struct buffer *b, struct modu
 	buf_printf(b, "#undef unix\n"); /* We have a module called "unix" */
 	buf_printf(b, "struct module __this_module\n");
 	buf_printf(b, "__attribute__((section(\".gnu.linkonce.this_module\"))) = 
{\n");
-	buf_printf(b, " .name = __stringify(KBUILD_MODNAME),\n");
+	buf_printf(b, " .name = KBUILD_MODNAME,\n");
 	if (mod->has_init)
 		buf_printf(b, " .init = init_module,\n");
 	if (mod->has_cleanup)

-- 
RomanU

Re: [PATCH] kbuild: using well known kernel symbols as module names.

[Thayumanavar Sachithanantham]

For me it works with single quotes. Anyhow it's okay. Thanks.

Regards,
Thayumanavar S.