Return-path: Received: from mail-gx0-f12.google.com ([209.85.217.12]:55804 "EHLO mail-gx0-f12.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752549AbYKCH3s (ORCPT ); Mon, 3 Nov 2008 02:29:48 -0500 Received: by gxk5 with SMTP id 5so789418gxk.13 for ; Sun, 02 Nov 2008 23:29:47 -0800 (PST) Message-ID: <43e72e890811022329g510a280wfd033538ee9b8c17@mail.gmail.com> (sfid-20081103_082952_258052_A0223963) Date: Sun, 2 Nov 2008 23:29:47 -0800 From: "Luis R. Rodriguez" To: "Johannes Berg" Subject: Re: wireless-testing commit eb9d4e8399181357cb6f6625ba7f849987432c6c causes stalls Cc: "Bob Copeland" , "Nick Kossifidis" , tim.gardner@canonical.com, mick@madwifi.org, linux-wireless@vger.kernel.org, "John W. Linville" In-Reply-To: <1225696692.3619.18.camel@johannes.berg> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 References: <4908B754.1050400@tpi.com> <43e72e890811011419k460b11e0he08d66022cbd606e@mail.gmail.com> <40f31dec0811020132o640afa49u56791b4122013463@mail.gmail.com> <40f31dec0811020110t6ec94c57gd91adc44f759bf45@mail.gmail.com> <20081102184146.GA6065@hash.localnet> <43e72e890811021249x6047b38do5d7ead10fe4098e7@mail.gmail.com> <1225696692.3619.18.camel@johannes.berg> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Sun, Nov 2, 2008 at 11:18 PM, Johannes Berg wrote: > On Sun, 2008-11-02 at 12:49 -0800, Luis R. Rodriguez wrote: >> On Sun, Nov 2, 2008 at 10:41 AM, Bob Copeland wrote: >> > On Sun, Nov 02, 2008 at 11:10:04AM +0200, Nick Kossifidis wrote: >> >> Can you test the attached patch ? >> >> >> >> It works for me (tested on a AR5413)... >> >> >> >> makis linux # iperf -s >> >> ------------------------------------------------------------ >> >> Server listening on TCP port 5001 >> >> TCP window size: 85.3 KByte (default) >> >> ------------------------------------------------------------ >> >> [ 4] local 192.168.1.104 port 5001 connected with 192.168.1.10 port 43192 >> >> [ ID] Interval Transfer Bandwidth >> >> [ 4] 0.0-10.6 sec 21.8 MBytes 17.2 Mbits/sec >> > >> > This patch works for me (I was seeing the same stalls). >> > >> > I somehow managed to trigger this after reloading the module: >> > >> > Nov 2 13:12:05 sludge kernel: ------------[ cut here ]------------ >> > Nov 2 13:12:05 sludge kernel: WARNING: at net/mac80211/main.c:236 >> > ieee80211_hw_config+0x82/0x8c [mac80211]() >> > Nov 2 13:12:05 sludge kernel: Modules linked in: ath5k af_packet >> > sha256_generic aes_i586 aes_generic cbc loop i915 drm binfmt_misc >> > acpi_cpufreq fan container nls_utf8 hfsplus dm_crypt dm_mod kvm_intel >> > kvm fuse sbp2 snd_hda_intel snd_pcm_oss snd_pcm snd_mixer_oss appletouch >> > hid_apple snd_seq_dummy snd_seq_oss arc4 ecb snd_seq_midi usbhid >> > snd_rawmidi snd_seq_midi_event mac80211 snd_seq ohci1394 snd_timer >> > snd_seq_device sr_mod ieee1394 sky2 cfg80211 sg cdrom rtc ehci_hcd >> > uhci_hcd thermal bitrev crc32 snd snd_page_alloc battery ac processor >> > button evdev unix [last unloaded: ath5k] >> > Nov 2 13:12:05 sludge kernel: Pid: 9748, comm: ath5k_pci Tainted: G >> > W 2.6.28-rc2-wl #19 >> > [...] >> > >> > But I think that was just a coincidence with the hardware getting >> > stuck in a bad state -- after reboot it was fine. If not, this at least >> > papers over the warning :) >> > >> > diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c >> > index a298e8a..0308165 100644 >> > --- a/drivers/net/wireless/ath5k/base.c >> > +++ b/drivers/net/wireless/ath5k/base.c >> > @@ -2796,7 +2796,8 @@ ath5k_config(struct ieee80211_hw *hw, u32 changed) >> > sc->bintval = conf->beacon_int; >> > sc->power_level = conf->power_level; >> > >> > - return ath5k_chan_set(sc, conf->channel); >> > + ath5k_chan_set(sc, conf->channel); >> > + return 0; >> > } >> >> Not sure I agree with the WARN_ON() if the driver's mac80211 config() >> callback fails. In our case when we tune to a different channel we >> have to clear any DMA operations first and then we reset the chip. >> Reseting the chip can fail for whatever strange hw issue cases. The >> patch fixes the complaint but is the complaint sane? > > What's mac80211 to do when it fails? How about a shiny new nl80211 event? Luis