Return-path: Received: from vserver.eikelenboom.it ([84.200.39.61]:38930 "EHLO smtp.eikelenboom.it" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755018AbaLIK0r (ORCPT ); Tue, 9 Dec 2014 05:26:47 -0500 Date: Tue, 9 Dec 2014 11:26:41 +0100 From: Sander Eikelenboom Message-ID: <1077310936.20141209112641@eikelenboom.it> (sfid-20141209_112651_094785_3E83A6F2) To: Johannes Berg CC: Intel Linux Wireless , linux-wireless@vger.kernel.org, Dan Williams Subject: Re: iwlwifi 6235 AGN: hardware limitation on number of stations that can connect in ap mode ? In-Reply-To: <1417853921.2046.1.camel@sipsolutions.net> References: <955277702.20141205105522@eikelenboom.it> (sfid-20141205_110059_932860_1A930067) <1417853921.2046.1.camel@sipsolutions.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-wireless-owner@vger.kernel.org List-ID: Saturday, December 6, 2014, 9:18:41 AM, you wrote: > Hi Sander, >> So i'm wondering is there a hardware limitation of stations that can connect to >> this mini-pci card in ap-mode ? > Yes, there's a hardware/firmware limitation of 16 "station entries". >> the first clients connect perfectly well but after 12 client have connected, for >> the 13th i get: >> >> [ 784.301106] wlan0: Allocated STA 00:0d:f0:2e:ee:02 >> [ 784.301117] wlan0: moving STA 00:0d:f0:2e:ee:02 to state 2 >> [ 784.301122] wlan0: moving STA 00:0d:f0:2e:ee:02 to state 3 >> [ 784.301141] iwlwifi 0000:00:05.0: Unable to prepare station 00:0d:f0:2e:ee:02 for addition >> [ 784.481399] iwlwifi 0000:00:05.0: Unable to add station 00:0d:f0:2e:ee:02 (-22) >> [ 784.647835] wlan0: Destroyed STA 00:0d:f0:2e:ee:02 >> [ 785.828588] wlan0: Allocated STA 00:0d:f0:2e:ee:02 >> [ 785.828600] wlan0: moving STA 00:0d:f0:2e:ee:02 to state 2 >> [ 785.828605] wlan0: moving STA 00:0d:f0:2e:ee:02 to state 3 >> [ 785.828624] iwlwifi 0000:00:05.0: Unable to prepare station 00:0d:f0:2e:ee:02 for addition >> [ 786.044379] iwlwifi 0000:00:05.0: Unable to add station 00:0d:f0:2e:ee:02 (-22) >> [ 786.219632] wlan0: Destroyed STA 00:0d:f0:2e:ee:02 > Right. I'm not exactly sure why we put -EINVAL rather than -ENOSPC or > something like that, but this is a limitation. >> If it is a hardware limitation, are there any other intel mini-pci adapters that >> don't have this hardware limitation (or at least a highter one). > With the newer 7260/7265 adapters you might be able to go up to 14 or 15 > stations (I haven't checked exactly), but that's not a significant > increase - the fundamental limit of 16 station entries is still there > and at least one is needed for internal tracking for multi-/broadcast > transmit transmit (and another one might be reserved for P2P on those > devices, and I might be forgetting another one perhaps which would mean > 13 is the max) > I don't believe that the driver (or even firmware) would be able to work > around this. > johannes Johannes / Dan, Thanks for the info and fast reply, very useful and appreciated ! It makes clear what i have to try and verify with other hardware/drivers, to see if i can get better results with that, unfortunately it's not something that is clearly communicated since it is a niche and most router chips are integrated, so it stays unclear if a same chipset is used on routers will behave the same on a mini-pcie card (the driver of course does if openwrt and thus linux can be used, but the hardware + firmware could be different. Any how, thanks again ! -- Sander