Bug 93131

Summary:	iwlwifi: when I use bluetooth speakers for audio output Wi-Fi stops working
Product:	Drivers	Reporter:	Stefan Nagy (stefan.nagy)
Component:	network-wireless	Assignee:	drivers_network-wireless (drivers_network-wireless)
Status:	CLOSED DOCUMENTED
Severity:	normal	CC:	ilw, linville
Priority:	P1
Hardware:	x86-64
OS:	Linux
See Also:	http://bugs.debian.org/777759
Kernel Version:	3.19.0	Subsystem:
Regression:	No	Bisected commit-id:
Attachments:	dmesg output lspci output

Description Stefan Nagy 2015-02-12 17:03:40 UTC

Created attachment 166601 [details]
dmesg output

Often when I use my bluetooth speakers for audio output, my Wi-Fi connection becomes unusable slow. When I stop the playback and wait a few seconds I can use Wi-Fi again.

The Wi-Fi connection never breaks completely, I stay connected but I can't even send or receive e-mails.

I'm affected by this bug on an HP Folio 13-2000 notebook with an Intel Corporation Centrino Wireless-N 1030 [Rainbow Peak] [8086:008b] adapter. Since I can't reproduce it with another notebook using the same WLAN and the same bluetooth speakers I guess it's hardware related.

I am affected by this bug on Debian Jessie (kernel v3.16): https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=777759

Since I wanted to know if it's an upstream bug I tested this with vanilla kernel 3.19 now. Please tell me if I can provide any more useful information.

Comment 1 Stefan Nagy 2015-02-12 17:04:08 UTC

Created attachment 166611 [details]
lspci output

Comment 2 Emmanuel Grumbach 2015-02-14 17:47:29 UTC

please try to disable bt_coex:

module parameter bt_coex_active=0 to iwlwifil

Comment 3 Stefan Nagy 2015-02-16 09:45:23 UTC

Thanks! It seems to help to disable bt_coex but I'll test this for some days and get back to you then.

Comment 4 Stefan Nagy 2015-02-17 17:43:12 UTC

OK, I don't need to test this for several days – it just works. I created a file /etc/modprobe.d/iwlwifi.conf with the following content:

options iwlwifi bt_coex_active=0

Since I did that and rebootet I can't reproduce this bug anymore.


BTW, this option has an unexpected side effect: It seems to have a very positiv effect on another bluetooth issue I first reported against pulseaudio and which was reassigned to bluez, see https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=776632

How should I proceed in this case? Sould I file another (vanilla) kernel bug report?

Comment 5 Stefan Nagy 2015-02-17 22:09:08 UTC

This bug was closed 'documented' – I guess this means that option bt_coex_active is documented somewhere [1].

I don't write bug reports because I want to find a solution that works _for me_ (for that purpose I'd use a forum or a mailing list). As ordinary user I'd expect my Wi-Fi adapter to just work, even if I dare to use bluetooth speakers for audio output. So I'll reopen this bug.



[1] Where? I couldn't find any useful information about the module option at the "main source of Documentation for the Linux wireless (IEEE-802.11) subsystem" (https://wireless.wiki.kernel.org/).

Comment 6 Emmanuel Grumbach 2015-02-18 06:40:54 UTC

Now it is:
https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi#bluetooth_coexistence

Comment 7 Stefan Nagy 2015-02-18 17:06:10 UTC

Thanks for adding the info about module option bt_coex_active to the official Linux Wireless wiki.

I'm sorry for beeing a pain in the neck, but why would you close this bug report? I really just don't understand this decision.

Comment 8 Emmanuel Grumbach 2015-02-18 17:16:16 UTC

because there's no way I can find the time to actually fix that.

Comment 9 Stefan Nagy 2015-02-19 09:27:28 UTC

I see, thanks!