On Wed, 2012-12-12 at 11:18 -0500, Solomon Peachy wrote: > On Wed, Dec 12, 2012 at 04:13:12PM +0100, Christian Lamparter wrote: > > Mac80211 already reserves at least 18 bytes tailroom [which can be > > allocated by a simple skb_put]. In fact p54 uses this tailroom to > > pass the MIC (8 bytes) + ICV (4 bytes) to the firmware. Do you need > > more than 18 bytes? > > I just went back and had a look at the code -- There were two related > workarounds: One made room for the MIC, but as you said, that hasn't > been necessary for a while so the code was disabled. > > The other workaround is still in place, however -- cw1200 also needs a > gap in the frame payload for the IV, even though it's generated by the > firmware. I worked around this by telling setting the > IEEE80211_KEY_FLAG_GENERATE_IV flag on the mac80211 keys, and then > zeroing that part of the payload when the frame went out to the harware. > > I figured it was a less costly approach than memmoving the whole payload > over by sizeof(ICV). > > Is there a better way to handle this now? There's IEEE80211_KEY_FLAG_PUT_IV_SPACE now which does exactly that. johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
