Unable to insmod hello_world kernel module in debian 8 - linux

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

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");

Answer 2

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.