From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?utf-8?Q?Bj=C3=B8rn_Mork?= Subject: Re: v3.8.5: "TCP: snd_cwnd is nul, please report this bug." Date: Mon, 08 Apr 2013 17:14:15 +0200 Message-ID: <87li8tyrzs.fsf@nemi.mork.no> References: <87zjx9pf13.fsf@nemi.mork.no> <1365431422.3887.10.camel@edumazet-glaptop> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Eric Dumazet , netdev@vger.kernel.org To: Eric Dumazet Return-path: Received: from canardo.mork.no ([148.122.252.1]:48366 "EHLO canardo.mork.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935911Ab3DHPO2 convert rfc822-to-8bit (ORCPT ); Mon, 8 Apr 2013 11:14:28 -0400 In-Reply-To: <1365431422.3887.10.camel@edumazet-glaptop> (Eric Dumazet's message of "Mon, 08 Apr 2013 07:30:22 -0700") Sender: netdev-owner@vger.kernel.org List-ID: Eric Dumazet writes: > On Mon, 2013-04-08 at 11:06 +0200, Bj=C3=B8rn Mork wrote: > >> Apr 8 10:58:09 nemi kernel: [152701.980799] TCP: snd_cwnd is nul, p= lease report this bug. >> Apr 8 10:58:33 nemi kernel: [152725.176151] iwlwifi 0000:03:00.0: f= ail to flush all tx fifo queues >> Apr 8 10:58:33 nemi kernel: [152725.185713] wlan0: authenticate wit= h 00:22:90:f9:23:a0 >> Apr 8 10:58:33 nemi kernel: [152725.185738] wlan0: capabilities/reg= ulatory prevented using AP HT/VHT configuration, downgraded >> Apr 8 10:58:33 nemi kernel: [152725.190150] wlan0: send auth to 00:= 22:90:f9:23:a0 (try 1/3) >> Apr 8 10:58:33 nemi kernel: [152725.199812] wlan0: authenticated >> Apr 8 10:58:33 nemi kernel: [152725.200020] iwlwifi 0000:03:00.0 wl= an0: disabling HT as WMM/QoS is not supported by the AP >> Apr 8 10:58:33 nemi kernel: [152725.200027] iwlwifi 0000:03:00.0 wl= an0: disabling VHT as WMM/QoS is not supported by the AP >> Apr 8 10:58:33 nemi kernel: [152725.204033] wlan0: associate with 0= 0:22:90:f9:23:a0 (try 1/3) >> Apr 8 10:58:33 nemi kernel: [152725.207317] wlan0: RX AssocResp fro= m 00:22:90:f9:23:a0 (capab=3D0x421 status=3D0 aid=3D12) >> Apr 8 10:58:33 nemi kernel: [152725.210745] wlan0: associated >>=20 > > Same issue was reported by Dave Jones on iwlwifi few days ago and I s= ent > following debugging patch, could you try it ? Will do. The patch only applied on top of net-next, so I assume that's what you want me to test it on? I looked through my logs and the 'fail to flush all tx fifo queues' warning from iwlwifi appears very infrequent. The last time before today was March 18th... Also accompanied by your warning. That's the only two times I've seen that one. And I've been running v3.8-rc7 (wher= e you introduced the warning) or newer since Feb 8th. So don't hold your breath. This may take a few weeks to trigger again. Bj=C3=B8rn