Hi all,
Just playing with the kernel code, I added a silly function
struct file_operations *get_socket_fileops ()
{
return &socket_file_ops;
}
at the bottom of net/socket.c, and
EXPORT_SYMBOL(get_socket_fileops);
into net/netsyms.c, expecting to be able to call this function
from a loadable module and to printk the function addresses
from the file_operations struct.
However, on rebooting into this modified kernel, my test module
fails to load, saying
foo.o: unresolved symbol get_socket_fileops
even though the symbol looks exported in vmlinux (nm) and
in /boot/System.map:
c020ca90 T get_socket_fileops
0c2b52bf ? __kstrtab_get_socket_fileops
0c2ba358 ? __ksymtab_get_socket_fileops
which looks exactly like sock_create, which the module *is*
able to address.
Any pointers?
thanks,
-prasad.
------------------------
V. Guruprasad ('prasad'),
http://www.columbia.edu/~vg96
On Mon, 29 Apr 2002, V. Guruprasad wrote:
> at the bottom of net/socket.c, and
>
> EXPORT_SYMBOL(get_socket_fileops);
>
> into net/netsyms.c, expecting to be able to call this function
> from a loadable module and to printk the function addresses
> from the file_operations struct.
>
> However, on rebooting into this modified kernel, my test module
> fails to load, saying
>
> foo.o: unresolved symbol get_socket_fileops
Basically, you're doing the right thing - what output does
grep get_socket_fileops /proc/ksyms
show?
Do you have CONFIG_MODVERSIONS turned on in your kernel config? If so,
you probably want to save your .config, make distclean and rebuild from
scratch - that will likely fix the problem.
--Kai
On Mon 2002.04.29, Kai Germaschewski wrote:
> Do you have CONFIG_MODVERSIONS turned on in your kernel config? If so,
> you probably want to save your .config, make distclean and rebuild from
> scratch - that will likely fix the problem.
Thanks, that solved it. Evidently, a 'make dep' was required which makes
#defines in include/linux/modules/netsyms.ver
thanks,
-p.
------------------------
V. Guruprasad ('prasad'),
http://www.columbia.edu/~vg96