Return-path: Received: from mail-qk0-f172.google.com ([209.85.220.172]:36746 "EHLO mail-qk0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751320AbcLEOFS (ORCPT ); Mon, 5 Dec 2016 09:05:18 -0500 Received: by mail-qk0-f172.google.com with SMTP id n21so346625874qka.3 for ; Mon, 05 Dec 2016 06:05:17 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1480946188.31788.6.camel@sipsolutions.net> References: <1480442753-6830-1-git-send-email-greearb@candelatech.com> <1480442753-6830-2-git-send-email-greearb@candelatech.com> <1480946188.31788.6.camel@sipsolutions.net> From: Michal Kazior Date: Mon, 5 Dec 2016 15:05:11 +0100 Message-ID: (sfid-20161205_150522_724454_4A889A44) Subject: Re: [PATCH 2/2] mac80211: put upper bound on txqi queue length. To: Johannes Berg Cc: Ben Greear , linux-wireless Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 5 December 2016 at 14:56, Johannes Berg wrot= e: > On Tue, 2016-11-29 at 10:05 -0800, greearb@candelatech.com wrote: >> From: Ben Greear >> >> This fixes OOM when using pktgen to drive a wifi station at more than >> the station can transmit. pktgen uses ndo_start_xmit instead of >> going >> through the queue layer, so it will not back off when the queues are >> stopped, and would thus cause packets to be added to the txqi->queue >> until the system goes OOM and crashes. >> >> Signed-off-by: Ben Greear >> --- >> >> This is against 4.7.10+, not sure if it is actually needed in latest >> kernel. > > One would hope that fq_tin_enqueue() does something like that, but > anyway the patch doesn't apply so I'm dropping it. fq_tin_enqueue() drops "fat" flow head packet upon reaching packet count limit (8192) or memory limit (4 or 16 mbytes depending on vht availability) whichever is hit first. Micha=C5=82