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=-1.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 2180EC43219 for ; Wed, 1 May 2019 11:06:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C8E3E21734 for ; Wed, 1 May 2019 11:06:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="oMhj4Edu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726352AbfEALGw (ORCPT ); Wed, 1 May 2019 07:06:52 -0400 Received: from mail-lj1-f196.google.com ([209.85.208.196]:44720 "EHLO mail-lj1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726052AbfEALGv (ORCPT ); Wed, 1 May 2019 07:06:51 -0400 Received: by mail-lj1-f196.google.com with SMTP id c6so8714124lji.11; Wed, 01 May 2019 04:06:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=eIL682wGpUi32jDyHiv4YP0KGP3S+mHvqENB0UUgtyM=; b=oMhj4EduRZ42J8NPXviNtYfkZPKJ7YbpNc8WdBcU+riYH67W3DL8sqJ49n2S+/EmAQ 13xl3uHh+fvqWwa2DdGBgOJkueJbtzz2oP8uHPafT/zQz6OYx2Zue0zIj7kbVJb5cOOU wYFiR566eev3SMFLDVZxA7s+VUZb+K/dTv7DfdN97ZT4IgWxwjgdJW70f+da00Q5uzSH 12tBV1OpOiRcgIr5vKBoILgKSJy0Ndf/SisB79kjzGV9Fco+7ehK4StyWr0YpDhrLRWj n6UtVgSExg2R17BXUTrA6NH6TpuiBUUoSVbSy8DMiShHJ+aaOlyEAWn9ta2CVzbn9xx9 lNOQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=eIL682wGpUi32jDyHiv4YP0KGP3S+mHvqENB0UUgtyM=; b=RhV0Ljylo5B/L/3ULeQMeW1g3xgje7BxcUO5TPMmECSQMYFRy5Z+BAZSEI0GnGdvIi PO0nLTfv/DMw/3sLxfAHKRL8vbzX75FsezBA9nv3KwIgpsnm0ghpgEOOA1ymM8Xarfjh 4dxaePPK1hdSO6HW0T9WtGb/XJDz7BjNM9L/cbjXBhlTd6/UYauAl1hlpd+USwvB7A6v xJpzDZQjzYhfq6excQ0qoHuqYuCrQyl66D7IqA8/yroaVEiLheee1xzFYC0mB6r8iESW yuOdKA13mc5brlkes6xrdt4W9YslaMMyxXJAcGnbOTTJVmvBfhXmbNDzqG1OvHYQx+KE hHpQ== X-Gm-Message-State: APjAAAUrmIN6dz/M6LymMTu/9fKYPR30m11Qj/+59ez/0RZ8L+gMCX0s hqoTJsT3vmv/cSPR1tO0eXBGrYu2 X-Google-Smtp-Source: APXvYqzBeP2zYtry4IBI2Iz6vl5syRChsbEVdT3BRJq343Eu3hIZE5Gky/xF+r2LMbI/e3Q+6Kux3w== X-Received: by 2002:a2e:2b16:: with SMTP id q22mr39437864lje.20.1556708809355; Wed, 01 May 2019 04:06:49 -0700 (PDT) Received: from [192.168.1.244] (81-233-89-221-no75.tbcn.telia.com. [81.233.89.221]) by smtp.gmail.com with ESMTPSA id z3sm320851ljg.78.2019.05.01.04.06.48 (version=TLS1_3 cipher=AEAD-AES128-GCM-SHA256 bits=128/128); Wed, 01 May 2019 04:06:48 -0700 (PDT) Subject: Re: [PATCH] mac80211: fix possible deadlock in TX path To: =?UTF-8?Q?Toke_H=c3=b8iland-J=c3=b8rgensen?= , johannes@sipsolutions.net, davem@davemloft.net, linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org References: <20190427204155.14211-1-erik.stromdahl@gmail.com> <87k1fcnd9y.fsf@toke.dk> From: Erik Stromdahl Message-ID: <656f3938-ef82-c1ce-753c-cb6b9d3c424b@gmail.com> Date: Wed, 1 May 2019 13:06:47 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: <87k1fcnd9y.fsf@toke.dk> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/30/19 9:49 AM, Toke Høiland-Jørgensen wrote: > Erik Stromdahl writes: > >> This patch fixes a possible deadlock when updating the TX statistics >> (when calling into ieee80211_tx_stats()) from ieee80211_tx_dequeue(). > > So is this the fix for the issue with TX scheduling you reported > earlier? :) > Actually not. I thought so initially, but then, after a few more test runs, I was able to run into the issue again. But it does seem to fix the other issue with the RCU stall since I haven't seen it with this patch applied (could be just a coincidence though). -- Erik