Re: [Ilw] RX laggy/choppy/stuck without TX on Intel Wireless 7260 with iwlwifi

[Emmanuel Grumbach <egrumbach@gmail.com>]

On 02/23/2014 09:02 AM, Grumbach, Emmanuel wrote:
>>
>> On Sat, Feb 22, 2014 at 10:18 PM, Grumbach, Emmanuel
>> <emmanuel.grumbach@intel.com> wrote:
>>>>
>>>> (Resending as plain text)
>>>>
>>>> I have a strange issue with my Intel Wireless 7260 adapter on my Dell XPS
>> 13
>>>> (Haswell). It seems that packets are received but aren't processed by the
>>>> kernel or something until more packets are transmitted. The net effect is
>>>> that the laptop's wireless seems somewhat choppy. I can demonstrate
>> this
>>>> by running something in a remote ssh session that generates periodic
>>>> output, and that output doesn't appear until I generate more outgoing
>>>> traffic. It's hard to describe it beyond that, but I took a screen capture
>> which
>>>> demonstrates this very well:
>>>> http://www.youtube.com/watch?v=4RMURSMszmc
>>>>
>>>> lspci shows the wireless card as: 02:00.0 Network controller: Intel
>> Corporation
>>>> Wireless 7260 (rev 6b) uname -a: Linux dalek 3.11.0-12-generic #19-
>> Ubuntu
>>>> SMP Wed Oct 9 16:20:46UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
>>>>
>>>> I googled this without success. I can gather diagnostic information if you
>> send
>>>> me instructions, I'm just not sure where to start or what to look for. Is this
>> a
>>>> bug in the driver? Maybe in the card microcode itself? Has anyone else
>>>> reported this issue? It seems very strange.
>>>> Any help is appreciated.
>>>
>>> Can you please send the output of dmesg?
>>> Tracing output can help too - but let's start with dmesg output.
>>>
>>
>> My full dmesg output is here: http://smkent.net/stuff/dmesg-dalek-
>> 20140222
>>
> 
> Your dmesg looks healthy
> 
>> Here's some selected output. I'm not sure if it's useful.
>>
>> smkent@dalek Desktop $ grep -ie iwl -e 80211 dmesg-dalek-20140222
>> [    3.968070] cfg80211: Calling CRDA to update world regulatory domain
>> [    3.976500] iwlwifi 0000:02:00.0: can't disable ASPM; OS doesn't
>> have ASPM control
>> [    3.976585] iwlwifi 0000:02:00.0: irq 59 for MSI/MSI-X
>> [    4.115345] iwlwifi 0000:02:00.0: loaded firmware version 22.1.7.0
>> op_mode iwlmvm
>> [    4.157435] iwlwifi 0000:02:00.0: Detected Intel(R) Dual Band
>> Wireless AC 7260, REV=0x144
>> [    4.157523] iwlwifi 0000:02:00.0: L1 Enabled; Disabling L0S
>> [    4.157691] iwlwifi 0000:02:00.0: L1 Enabled; Disabling L0S
>> [    4.269377] cfg80211: World regulatory domain updated:
>> [    4.269383] cfg80211:   (start_freq - end_freq @ bandwidth),
>> (max_antenna_gain, max_eirp)
>> [    4.269387] cfg80211:   (2402000 KHz - 2472000 KHz @ 40000 KHz),
>> (300 mBi, 2000 mBm)
>> [    4.269390] cfg80211:   (2457000 KHz - 2482000 KHz @ 40000 KHz),
>> (300 mBi, 2000 mBm)
>> [    4.269393] cfg80211:   (2474000 KHz - 2494000 KHz @ 20000 KHz),
>> (300 mBi, 2000 mBm)
>> [    4.269396] cfg80211:   (5170000 KHz - 5250000 KHz @ 40000 KHz),
>> (300 mBi, 2000 mBm)
>> [    4.269399] cfg80211:   (5735000 KHz - 5835000 KHz @ 40000 KHz),
>> (300 mBi, 2000 mBm)
>> [    4.379283] ieee80211 phy0: Selected rate control algorithm 'iwl-mvm-rs'
>> [    4.709497] iwlwifi 0000:02:00.0: L1 Enabled; Disabling L0S
>> [    4.709671] iwlwifi 0000:02:00.0: L1 Enabled; Disabling L0S
>> [ 9676.817175] cfg80211: Calling CRDA to update world regulatory domain
>> [ 9676.823809] cfg80211: World regulatory domain updated:
>> [ 9676.823820] cfg80211:   (start_freq - end_freq @ bandwidth),
>> (max_antenna_gain, max_eirp)
>> [ 9676.823827] cfg80211:   (2402000 KHz - 2472000 KHz @ 40000 KHz),
>> (300 mBi, 2000 mBm)
>> [ 9676.823834] cfg80211:   (2457000 KHz - 2482000 KHz @ 40000 KHz),
>> (300 mBi, 2000 mBm)
>> [ 9676.823840] cfg80211:   (2474000 KHz - 2494000 KHz @ 20000 KHz),
>> (300 mBi, 2000 mBm)
>> [ 9676.823846] cfg80211:   (5170000 KHz - 5250000 KHz @ 40000 KHz),
>> (300 mBi, 2000 mBm)
>> [ 9676.823851] cfg80211:   (5735000 KHz - 5835000 KHz @ 40000 KHz),
>> (300 mBi, 2000 mBm)
>> [ 9680.014722] iwlwifi 0000:02:00.0: L1 Enabled; Disabling L0S
>> [ 9680.014890] iwlwifi 0000:02:00.0: L1 Enabled; Disabling L0S
>>
>> I haven't taken a kernel trace before but I'm happy to do so if you
>> can point me toward some instructions.
>>
> 
> as root:
> trace-cmd record -e iwlwifi -e iwlwifi_msg.
> 
> Reproduce the bug while it's running. Stop with Ctrl+C when the bug reproduced.
> This will produce a trace.dat file which you can compress and send over email.
> 

Could you please try to reproduce with power save disabled?

options iwlmvm power_scheme=1

Thanks.