Unable to insmod hello_world kernel module in debian 8

Question

I can't get why insmod gives Invalid parameters error (can't see anything in dmesg):

$ sudo insmod hello.ko
insmod: ERROR: could not insert module hello.ko: Invalid parameters

$ sudo insmod /hello.ko
insmod: ERROR: could not load module /hello.ko: No such file or directory

I have no parameters in my module. It is just hello world example.

My environment:

$ uname -r
3.16.0-4-amd64

I have installed all possible kernel headers packages:

linux-headers-3.16.0-4-all
linux-headers-3.16.0-4-all-amd64
linux-headers-3.16.0-4-amd64
linux-headers-3.16.0-4-common
linux-headers-amd64 

My code:

#include <linux/module.h>   /* Needed by all modules */
#include <linux/kernel.h>   /* Needed for KERN_INFO */

int init_module(void)
{
    printk(KERN_INFO "Hello world 1.\n");
    return 0;
}

void cleanup_module(void)
{
    printk(KERN_INFO "Goodbye world 1.\n");
}

MODULE_LICENSE("GPL");

I use following Makefile:

obj-m += hello.o

all:
    make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules

clean:
    make -C /lib/modules/$(shell uname -r)/build M=$(PWD) clean

make output:

$ make

make -C /lib/modules/3.16.0-4-amd64/build M=/home/user/c.driver/driver-1 modules
make[1]: Entering directory '/usr/src/linux-headers-3.16.0-4-amd64'
Makefile:10: *** mixed implicit and normal rules: deprecated syntax
make[1]: Entering directory `/usr/src/linux-headers-3.16.0-4-amd64'
  CC [M]  /home/user/c.driver/driver-1/hello.o
  Building modules, stage 2.
  MODPOST 1 modules
  CC      /home/user/c.driver/driver-1/hello.mod.o
  LD [M]  /home/user/c.driver/driver-1/hello.ko
make[1]: Leaving directory '/usr/src/linux-headers-3.16.0-4-amd64'

Update: same result with 14.04.1-Ubuntu

Answer 1

For me, the issue was that that module file was in a shared folder (in fact, my Ubuntu box is a VM on Parallels). Copy the module to a local folder and try again.

Thanks to @avasin for this. The answer was in the comments but not quick to find, so adding it here as it may help others. This held me up for a couple of hours.

Answer 2

maybe it's because you forget that:

module_init(init_module);                                                           
module_exit(cleanup_module);

and I usually declare init_module() and cleanup_module() as a static function. and fellowing code are my kernel module template:

#include <linux/module.h>
#include <linux/kernel.h>

static int init_module(void)
{
   ... 
   return 0;
}

static void exit_module(void)
{
   ...
}

module_init(init_module);
module_exit(exit_module);
MODULE_LICENSE("GPL");