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 EB5CDC3A5A4 for ; Fri, 30 Aug 2019 09:03:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C1C862073F for ; Fri, 30 Aug 2019 09:03:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727236AbfH3JDy (ORCPT ); Fri, 30 Aug 2019 05:03:54 -0400 Received: from s3.sipsolutions.net ([144.76.43.62]:33232 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725780AbfH3JDx (ORCPT ); Fri, 30 Aug 2019 05:03:53 -0400 Received: by sipsolutions.net with esmtpsa (TLS1.3:ECDHE_SECP256R1__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.92.1) (envelope-from ) id 1i3cox-00026D-St; Fri, 30 Aug 2019 11:03:51 +0200 Message-ID: Subject: Re: [RFCv2 1/4] nl80211: Fix broken non-split wiphy dumps From: Johannes Berg To: Denis Kenzior , linux-wireless@vger.kernel.org Date: Fri, 30 Aug 2019 11:03:51 +0200 In-Reply-To: <20190816192703.12445-1-denkenz@gmail.com> (sfid-20190816_212729_636741_39C4CEB6) References: <20190816192703.12445-1-denkenz@gmail.com> (sfid-20190816_212729_636741_39C4CEB6) 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, 2019-08-16 at 14:27 -0500, Denis Kenzior wrote: > If a (legacy) client requested a wiphy dump but did not provide the > NL80211_ATTR_SPLIT_WIPHY_DUMP attribute, the dump was supposed to be > composed of purely non-split NEW_WIPHY messages, with 1 wiphy per > message. At least this was the intent after commit: > 3713b4e364ef ("nl80211: allow splitting wiphy information in dumps") > > However, in reality the non-split dumps were broken very shortly after. > Perhaps around commit: > fe1abafd942f ("nl80211: re-add channel width and extended capa advertising") Fun. I guess we updated all userspace quickly enough to not actually have any issues there. As far as I remember, nobody ever complained, so I guess people just updated their userspace. Given that it's been 6+ years, maybe we're better off just removing the whole non-split thing then, instead of fixing it. Seems even less likely now that somebody would run a 6+yo supplicant (from before its commit c30a4ab045ce ("nl80211: Fix mode settings with split wiphy dump")). OTOH, this is a simple fix, would removing the non-split mode result in any appreciable cleanups? Perhaps not, and we'd have to insert something instead to reject non-split and log a warning, or whatnot. johannes