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=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=unavailable 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 0AD1FC10F03 for ; Fri, 1 Mar 2019 16:06:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD0772085A for ; Fri, 1 Mar 2019 16:06:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=nbd.name header.i=@nbd.name header.b="WoNQ+cHn" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388855AbfCAQGw (ORCPT ); Fri, 1 Mar 2019 11:06:52 -0500 Received: from nbd.name ([46.4.11.11]:57018 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727952AbfCAQGw (ORCPT ); Fri, 1 Mar 2019 11:06:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=nbd.name; s=20160729; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=K8jR4Oq+8wTX075lC3UXO9BAEiKpnRH1hK/RY23mxU4=; b=WoNQ+cHnj+pPHQpUVjZlyKTV3n Req0KYnY8c11HMmOJYJLolgA+d+befl7GCAl2WLStV7gbZzklD5CPw+M/KS9D77Ve22O4SrPhzwVL fi6yCccrofQI1TjXXrH1tpwmfhuDllNu6rMEY629RLyjQgYL91/O/lZZB4bsBrvgbKLw=; Subject: Re: [PATCH] mac80211: do not call driver wake_tx_queue op during reconfig To: Ben Greear , linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net, stable@vger.kernel.org References: <20190301134837.88087-1-nbd@nbd.name> <09a12ed0-dd86-2077-9ecb-c62a52186952@candelatech.com> From: Felix Fietkau Openpgp: preference=signencrypt Autocrypt: addr=nbd@nbd.name; prefer-encrypt=mutual; keydata= mQGiBEah5CcRBADIY7pu4LIv3jBlyQ/2u87iIZGe6f0f8pyB4UjzfJNXhJb8JylYYRzIOSxh ExKsdLCnJqsG1PY1mqTtoG8sONpwsHr2oJ4itjcGHfn5NJSUGTbtbbxLro13tHkGFCoCr4Z5 Pv+XRgiANSpYlIigiMbOkide6wbggQK32tC20QxUIwCg4k6dtV/4kwEeiOUfErq00TVqIiEE AKcUi4taOuh/PQWx/Ujjl/P1LfJXqLKRPa8PwD4j2yjoc9l+7LptSxJThL9KSu6gtXQjcoR2 vCK0OeYJhgO4kYMI78h1TSaxmtImEAnjFPYJYVsxrhay92jisYc7z5R/76AaELfF6RCjjGeP wdalulG+erWju710Bif7E1yjYVWeA/9Wd1lsOmx6uwwYgNqoFtcAunDaMKi9xVQW18FsUusM TdRvTZLBpoUAy+MajAL+R73TwLq3LnKpIcCwftyQXK5pEDKq57OhxJVv1Q8XkA9Dn1SBOjNB l25vJDFAT9ntp9THeDD2fv15yk4EKpWhu4H00/YX8KkhFsrtUs69+vZQwbQcRmVsaXggRmll dGthdSA8bmJkQG5iZC5uYW1lPohgBBMRAgAgBQJGoeQnAhsjBgsJCAcDAgQVAggDBBYCAwEC HgECF4AACgkQ130UHQKnbvXsvgCgjsAIIOsY7xZ8VcSm7NABpi91yTMAniMMmH7FRenEAYMa VrwYTIThkTlQuQINBEah5FQQCACMIep/hTzgPZ9HbCTKm9xN4bZX0JjrqjFem1Nxf3MBM5vN CYGBn8F4sGIzPmLhl4xFeq3k5irVg/YvxSDbQN6NJv8o+tP6zsMeWX2JjtV0P4aDIN1pK2/w VxcicArw0VYdv2ZCarccFBgH2a6GjswqlCqVM3gNIMI8ikzenKcso8YErGGiKYeMEZLwHaxE Y7mTPuOTrWL8uWWRL5mVjhZEVvDez6em/OYvzBwbkhImrryF29e3Po2cfY2n7EKjjr3/141K DHBBdgXlPNfDwROnA5ugjjEBjwkwBQqPpDA7AYPvpHh5vLbZnVGu5CwG7NAsrb2isRmjYoqk wu++3117AAMFB/9S0Sj7qFFQcD4laADVsabTpNNpaV4wAgVTRHKV/kC9luItzwDnUcsZUPdQ f3MueRJ3jIHU0UmRBG3uQftqbZJj3ikhnfvyLmkCNe+/hXhPu9sGvXyi2D4vszICvc1KL4RD aLSrOsROx22eZ26KqcW4ny7+va2FnvjsZgI8h4sDmaLzKczVRIiLITiMpLFEU/VoSv0m1F4B FtRgoiyjFzigWG0MsTdAN6FJzGh4mWWGIlE7o5JraNhnTd+yTUIPtw3ym6l8P+gbvfoZida0 TspgwBWLnXQvP5EDvlZnNaKa/3oBes6z0QdaSOwZCRA3QSLHBwtgUsrT6RxRSweLrcabiEkE GBECAAkFAkah5FQCGwwACgkQ130UHQKnbvW2GgCfTKx80VvCR/PvsUlrvdOLsIgeRGAAn1ee RjMaxwtSdaCKMw3j33ZbsWS4 Message-ID: Date: Fri, 1 Mar 2019 17:06:48 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 MIME-Version: 1.0 In-Reply-To: <09a12ed0-dd86-2077-9ecb-c62a52186952@candelatech.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On 2019-03-01 16:29, Ben Greear wrote: > On 3/1/19 5:48 AM, Felix Fietkau wrote: >> There are several scenarios in which mac80211 can call drv_wake_tx_queue >> after ieee80211_restart_hw has been called and has not yet completed. >> Driver private structs are considered uninitialized until mac80211 has >> uploaded the vifs, stations and keys again, so using private tx queue >> data during that time is not safe. >> >> The driver can also not rely on drv_reconfig_complete to figure out when >> it is safe to accept drv_wake_tx_queue calls again, because it is only >> called after all tx queues are woken again. >> >> To fix this, bail out early in drv_wake_tx_queue if local->in_reconfig >> is set. > > This reminded me of a patch I posted back in 2016. The discussion just sort of > ended on it, but curious if you have a new opinion on it after debugging the > issue in this patch: > > https://patchwork.kernel.org/patch/9457709/ > > For what its worth, I've been using the patch above since I posted it, and > it seems to work well for ath9k and ath10k. I agree with what Johannes wrote about that patch. Fixing this could likely be as simple as clearing IEEE80211_SDATA_IN_DRIVER on all interfaces before bringing any of them back up. That way the normal interface add logic applies without nasty special cases. The reconfig code checks for ieee80211_sdata_running (which is unaffected), so I don't think we need to save the previous value of that flag. - Felix