Code:

root@kali - $ patch -p1 < compatdrivers_chan_qos_frag.patch
patching file drivers/net/wireless/rtl818x/rtl8187/dev.c
Hunk #1 succeeded at 251 (offset -1 lines).
patching file net/mac80211/cfg.c
Hunk #1 FAILED at 826.
1 out of 1 hunk FAILED -- saving rejects to file net/mac80211/cfg.c.rej
patching file net/mac80211/tx.c
Hunk #1 FAILED at 1482.
1 out of 1 hunk FAILED -- saving rejects to file net/mac80211/tx.c.rej
patching file net/wireless/chan.c
patch unexpectedly ends in middle of line
Hunk #1 succeeded at 689 with fuzz 1 (offset 209 lines).
that is problably hapenning because who created the thread does now know very well how things work .

these are his instructions ::
Downloading a frag+ack patch
sudo wget http://patches.aircrack-ng.org/mac80...g+ack_v1.patch

applying that patch :
sudo patch -p1 < mac80211.compat08082009.wl_frag+ack_v1.patch

and then he tells everybody to download another frag+ack patch because it have the correct offset !!!
Downloading
sudo wget -Ocompatdrivers_chan_qos_frag.patch http://www.pastie.org/pastes/8846771/download

patching again !!!!
patch -p1 < compatdrivers_chan_qos_frag.patch

so why did he write the first patch ?

and to terminate he tells to download the patch to ignore the negative channel on airodump-ng
sudo wget -Ofix-channel-negative-1-on-new-backport-by-Devil_D.patch http://pastebin.com/wPwAJaQC

and patch it .

patch -p1 < fix-channel-negative-1-on-new-backpo

this is the most confuse explanation in this forum .
I downloaded the latest backports 3.17 rc3 , and i am figuring out how to do it correctly , but i think you only need these patches : 1 & 3 , or 2 & 3 , and not 1,2,3 .