From: Ben Greear <greearb@candelatech.com> To: Johannes Berg <johannes@sipsolutions.net>, Oleksij Rempel <linux@rempel-privat.de>, "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>, ath10k <ath10k@lists.infradead.org>, kirtika@google.com Subject: Re: Setting single rate in ath10k broken by "reject/clear user rate mask if not usable" Date: Wed, 18 Oct 2017 14:30:38 -0700 [thread overview] Message-ID: <0bfb289d-a9fa-03d9-f9c7-cc0d01b0bd43@candelatech.com> (raw) In-Reply-To: <1508360527.2674.61.camel@sipsolutions.net> On 10/18/2017 02:02 PM, Johannes Berg wrote: > On Wed, 2017-10-18 at 13:51 -0700, Ben Greear wrote: >> " >> I guess you could implement this part? I.e. iterating the clients and >> checking that they all support the rate that is set. However, then you >> also need to implement that this gets reset when a new client that >> doesn't support this rate connects. >> " >> >> The first part seems OK, but the second seems like a pain. Maybe just >> keep a new client from being able to connect at all if it doesn't support >> any available rates? > > I suppose if you reject the NEW_STATION command, then hostapd will > reject the association though, so it's probably not hard to do. > However, I'm not really sure why you'd want that? If you do want that > then basically you're just implemented a very roundabout way of adding > this rate to the basic rates, so you might as well just add it and work > with the current basic rates check? If a user specifies a specific rate or rate-set, then I do not think we should quietly change it out from under them. So, we could check at the time the rate-set is applied (all current peers). We can reject the change at that point if one of the peers does not support any common rates. And, whenever a peer tries to be associated, we can check that there is some common rateset in place. If there is no common rateset, then reject the association one way or another. > We'll need to be a little careful what happens with client-mode > interfaces, which is where we actually observed hitting the WARN_ON() > about not having any rates at all, but I think I already put a reset of > the rates there anyway if they're not compatible with the AP. At least > that's easier because there's only one client. It would be easy to configure a station to do VHT MCS 8 only, and then it would never be able to associate with an HT AP, for instance. I don't think this should be a WARN_ON event, just a failure. It would be great if we could get a useful error message back to the caller, but I am not sure how feasible that is with the current netlink and mac80211 code. If your main concern is hitting a WARN_ON, maybe just change it to a quieter error message or remove it entirely and just return a failure code? Thanks, Ben > > johannes > -- Ben Greear <greearb@candelatech.com> Candela Technologies Inc http://www.candelatech.com
WARNING: multiple messages have this Message-ID (diff)
From: Ben Greear <greearb@candelatech.com> To: Johannes Berg <johannes@sipsolutions.net>, Oleksij Rempel <linux@rempel-privat.de>, "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>, ath10k <ath10k@lists.infradead.org>, kirtika@google.com Subject: Re: Setting single rate in ath10k broken by "reject/clear user rate mask if not usable" Date: Wed, 18 Oct 2017 14:30:38 -0700 [thread overview] Message-ID: <0bfb289d-a9fa-03d9-f9c7-cc0d01b0bd43@candelatech.com> (raw) In-Reply-To: <1508360527.2674.61.camel@sipsolutions.net> On 10/18/2017 02:02 PM, Johannes Berg wrote: > On Wed, 2017-10-18 at 13:51 -0700, Ben Greear wrote: >> " >> I guess you could implement this part? I.e. iterating the clients and >> checking that they all support the rate that is set. However, then you >> also need to implement that this gets reset when a new client that >> doesn't support this rate connects. >> " >> >> The first part seems OK, but the second seems like a pain. Maybe just >> keep a new client from being able to connect at all if it doesn't support >> any available rates? > > I suppose if you reject the NEW_STATION command, then hostapd will > reject the association though, so it's probably not hard to do. > However, I'm not really sure why you'd want that? If you do want that > then basically you're just implemented a very roundabout way of adding > this rate to the basic rates, so you might as well just add it and work > with the current basic rates check? If a user specifies a specific rate or rate-set, then I do not think we should quietly change it out from under them. So, we could check at the time the rate-set is applied (all current peers). We can reject the change at that point if one of the peers does not support any common rates. And, whenever a peer tries to be associated, we can check that there is some common rateset in place. If there is no common rateset, then reject the association one way or another. > We'll need to be a little careful what happens with client-mode > interfaces, which is where we actually observed hitting the WARN_ON() > about not having any rates at all, but I think I already put a reset of > the rates there anyway if they're not compatible with the AP. At least > that's easier because there's only one client. It would be easy to configure a station to do VHT MCS 8 only, and then it would never be able to associate with an HT AP, for instance. I don't think this should be a WARN_ON event, just a failure. It would be great if we could get a useful error message back to the caller, but I am not sure how feasible that is with the current netlink and mac80211 code. If your main concern is hitting a WARN_ON, maybe just change it to a quieter error message or remove it entirely and just return a failure code? Thanks, Ben > > johannes > -- Ben Greear <greearb@candelatech.com> Candela Technologies Inc http://www.candelatech.com _______________________________________________ ath10k mailing list ath10k@lists.infradead.org http://lists.infradead.org/mailman/listinfo/ath10k
next prev parent reply other threads:[~2017-10-18 21:30 UTC|newest] Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top 2017-10-10 20:54 Setting single rate in ath10k broken by "reject/clear user rate mask if not usable" Ben Greear 2017-10-10 20:54 ` Ben Greear 2017-10-11 4:37 ` Not able to set single rate in ath10k (backports-4.14-rc2-1) KAVITA MATHUR 2017-10-11 8:02 ` Setting single rate in ath10k broken by "reject/clear user rate mask if not usable" Johannes Berg 2017-10-11 8:02 ` Johannes Berg 2017-10-11 8:07 ` Johannes Berg 2017-10-11 8:07 ` Johannes Berg 2017-10-11 14:51 ` Ben Greear 2017-10-11 14:51 ` Ben Greear 2017-10-18 7:33 ` Johannes Berg 2017-10-18 7:33 ` Johannes Berg 2017-10-18 14:50 ` Ben Greear 2017-10-18 14:50 ` Ben Greear 2017-10-18 17:56 ` Oleksij Rempel 2017-10-18 17:56 ` Oleksij Rempel 2017-10-18 20:34 ` Johannes Berg 2017-10-18 20:34 ` Johannes Berg 2017-10-18 20:51 ` Ben Greear 2017-10-18 20:51 ` Ben Greear 2017-10-18 21:02 ` Johannes Berg 2017-10-18 21:02 ` Johannes Berg 2017-10-18 21:30 ` Ben Greear [this message] 2017-10-18 21:30 ` Ben Greear 2017-10-25 15:17 ` Johannes Berg 2017-10-25 15:17 ` Johannes Berg 2017-10-25 16:13 ` Ben Greear 2017-10-25 16:13 ` Ben Greear 2017-10-27 20:15 ` Johannes Berg 2017-10-27 20:15 ` Johannes Berg 2017-10-27 20:41 ` Ben Greear 2017-10-27 20:41 ` Ben Greear 2017-11-13 10:09 ` Johannes Berg 2017-11-13 10:09 ` Johannes Berg 2017-11-13 17:05 ` Ben Greear 2017-11-13 17:05 ` Ben Greear
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