From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 717F6C47404 for ; Mon, 7 Oct 2019 21:11:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4FA0D2133F for ; Mon, 7 Oct 2019 21:11:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729346AbfJGVLm (ORCPT ); Mon, 7 Oct 2019 17:11:42 -0400 Received: from s3.sipsolutions.net ([144.76.43.62]:46742 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728273AbfJGVLm (ORCPT ); Mon, 7 Oct 2019 17:11:42 -0400 Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.92.2) (envelope-from ) id 1iHaI8-0001fg-A1; Mon, 07 Oct 2019 23:11:40 +0200 Message-ID: Subject: Re: [PATCH 2/2] mac80211: Support LIVE_ADDRESS_CHANGE feature From: Johannes Berg To: James Prestwood , linux-wireless@vger.kernel.org Date: Mon, 07 Oct 2019 23:11:38 +0200 In-Reply-To: <90ae00044bc0834d87d3f9fb75ce63dce4cfadd5.camel@gmail.com> (sfid-20191004_182756_493717_F6EB75F5) References: <20190913195908.7871-1-prestwoj@gmail.com> <20190913195908.7871-2-prestwoj@gmail.com> (sfid-20190913_220113_985031_7C3A66BD) <90ae00044bc0834d87d3f9fb75ce63dce4cfadd5.camel@gmail.com> (sfid-20191004_182756_493717_F6EB75F5) Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.30.5 (3.30.5-1.fc29) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Fri, 2019-10-04 at 09:25 -0700, James Prestwood wrote: > > > I'm not even entirely sure it _is_ needed - if we've still not > > created > > the IBSS but are scanning for it or trying to merge the MAC address > > won't really matter yet? Probably? > > I guess its just paranoia, rather be safe than sorry. I can take this > out, but is "Probably?" a good reason? ;) Fair enough, nobody really cares about IBSS anyway ;-) I guess I was mostly wondering if you had noticed anything that would actually be a problem. > Ok so no switch statement, simply just check that we aren't offchannel > or scanning. I guess this would then cover the IBSS case too. Don't think it covers IBSS - that one is really specially accessing some IBSS data. > > If you do care about this being more granular then you should check > > *which* interface is scanning, and then you can still switch the MAC > > address for *other* interfaces - but I'd still argue it should be > > independent of interface type. > > I think maybe in the future we might want this, but for now lets not > worry about it. But just to make sure we are on the same page, your > talking about e.g. hardware with multiple radios so you could be doing > offchannel work/scanning/connecting simultaneously without having to > wait for the current operation to complete? Not really multiple radios, who cares? Just multiple interfaces would be sufficient. You're just removing/adding some interface (as far as the driver is concerned) - doesn't matter if you actually are scanning or something on another interface right? > > And, I'm confused, but isn't the polarity of the scanning check > > wrong? > > Ah yeah, after you pointed that out I realized 'scanning' is a bit > field. I should be doing: > > test_bit(SCAN_HW_SCANNING, &sdata->local->scanning) I think checking for all the bits is fine (and necessary, just HW scan is unlikely to be enough, changing the MAC address would also disrupt a software scan) - just need to invert the polarity? > Either way I'll send another patch with these things addressed. I'll wait, thanks. johannes