[Top] [All Lists]

RE: RE: Information required

To: Dan Aizenstros <>
Subject: RE: RE: Information required
From: Adeel Malik <>
Date: Fri, 29 Aug 2003 16:21:40 +0500
Original-recipient: rfc822;
Hi Dan,
       I have tried -mlong-calls option to the compiler, but is still gives
"unable to resolve printk" when I insmod the LKM.
When I 'cat' the /proc/ksyms, it shows printk_Rcxyz.... When I disable the
MODVERSIONING by using 'make menuconfig' during kernel configuration
process, and build the kernel again for MIPS platform, the proc/ksyms still
shows the printk_Rcxyz ... i.e, function name with a suffix.
Can you elaborate as to what are the steps needed to build the kernel with
MODVERSIONING disabled, etc.....


-----Original Message-----
From: Dan Aizenstros []
Sent: Thursday, August 28, 2003 8:43 PM
Subject: Re: RE: Information required

Hello Adeel,

You need to pass -mlong-calls to the compiler.
You can add it the CFLAGS.


Dan Aizenstros
Software Engineering Manager
QuickLogic Canada

>>> Adeel Malik <> 08/28/03 08:22 AM >>>
Hello Jun,

Thanks for the reply.I have checked for the unresolved function symbols like
"printk" and "register_chrdev", and found that they are present in
/proc/ksyms. So it appears to me that I may be compiling the module with
incorrect parameters.

Below is the Makefile for the Loadable Module:



TARGET = example_driver

INCLUDE = /backup/buildroot-QuickMIPS/build/linux-2.4.20/include


CFLAGS = -DMODVERSIONS -I${INCLUDE}/linux/modversions.h

${TARGET}.o: ${TARGET}.c

.PHONY: clean


rm -rf ${TARGET}.o


Do you think that I need to modify the makefile or add some more options to

I have ensured that the kernel is compiled with "module-option" turned on.

Also my module uses symbol versioning (sometimes called module versioning).

I use the following lines of code at the start of header file to accomplish


#if defined (CONFIG_MODVERSIONS) && ! defined (MODVERSIONS)

#include <linux/modversions.h>




I have successfully cross-compiled user-space applications on the target
platform. Only when i do the kernel work, this unresolved symbol (like
printk, register_chrdev, etc..) phenomenon happens.



-----Original Message-----


[]On Behalf Of Jun Sun

Sent: Wednesday, August 27, 2003 9:51 PM

To: Adeel Malik


Subject: Re: Information required


On Wed, Aug 27, 2003 at 07:30:26PM +0500, Adeel Malik wrote:

> Hi All,

> I am involved in Embedded Linux Development for MIPS Processor. I

> need to write a device driver for a MIPS Target Platform. When I insmod

> driver.o file, the linux bash script running on the target hardware gives

> the error message like ;

> 1. unable to resolve the printk function

> 2. unable to resolve the register_chardev function

> etc.

> Can you plz give me the direction as to how to proceed to tackle this

> situation.

Make sure your kernel compiled with module option turned on.

Does it use module version (CONFIG_MODVERSIONS)?

If so, add -DMODVERSIONS -include $(KERNEL_PATH)/include/linux/modversions.h

to your CFLAGS.



<Prev in Thread] Current Thread [Next in Thread>