[SOLVED]
first enter lspci -nn | grep 0200
and make sure that your drivers is "Qualcomm Atheros QCA8172 Fast Ethernet[1969:10a0]"
The following fix is is only going to work for-
1969:1091 - AR8161 Gigabit Ethernet
1969:1090 - AR8162 Fast Ethernet
1969:10A1 - QCA8171 Gigabit Ethernet
1969:10A0 - QCA8172 Fast Ethernet
adapters. and please make sure that your kernel is 2.6.24 or above. It is technically possible for kernels < 2.6.24 but might take some work. (still worth giving a try!)
to check the kernel version type
uname -a
after that, If they are all neat and right.
download compat-drivers-2013-03-04-u.tar.bz2 file and extract it.
go to the extracted directory [ex- cd Downloads/compat-drivers-2013-03-04-u/
]
and type-
sudo ./scripts/driver-select alx
sudo make
sudo make install
reboot the system you are all done :)
apparently this type of ethernet adapters are available in lenovo g500s, lenovo g500 series, lenovo g400 series, asus 3rd gen laptops, (you better check before installing)
for more information go to http://www.linuxfoundation.org
Thanks to Lusus Naturae. His forum showed me this way. so the rewards goes to him. [original link-]
http://meinewenigkeit.blogspot.com/2013/08/gentoo-and-atheros-qca8172-fast-ethernet.html