Re: [Ilw] Intel Wireless 7260 hardware timed out randomly

[Bjorn Helgaas <bhelgaas@google.com>]

[-cc linux-pci]

On Mon, Jan 13, 2014 at 1:26 AM, Grumbach, Emmanuel
<emmanuel.grumbach@intel.com> wrote:
>> Hi,
>>
>> I am sorry but here is bad news.
>>
>> During previous debugging process, I have a modconf file
>> /etc/modprobe.d/iwlwifi.conf, containing "options iwlmvm
>> power_scheme=1". I removed it just now (Emmanuel says I can remove it
>> now) and encountered (maybe) new bugs. Here is what I did just now:
>>
>> 0. Current kernel: patched with
>> https://bugzilla.kernel.org/attachment.cgi?id=121671&action=diff ;
>> setpci trick: none ; NIC status: works nice after ~16 hours heavy
>> usage.
>> 1. Delete that modconf file, reboot.
>> 2. Network connection becomes painfully laggy and lossy.
>> 3. Re-create that modconf file, reboot.
>> 4. Network connection works fine.
>> 5. Comment out that line, reboot.
>> 6. Network connection becomes painfully laggy and lossy.
>> 7. Uncomment that line, reboot.
>> 8. Network connection works fine.
>>
>> What I mean "painfully laggy and lossy" is that, to whomever I "ping"
>> (Google, 8.8.8.8, local DNS server...), the RTT is rather high than
>> normal, and packet loss rate is above 90% (some addresses 100% loss).
>> While at the same time, other network device in the same LAN works
>> fine.
>>
>> I've attached dmesg and lspci output at step 6 and 8.
>>
>
> Are you sure about step 1 and 5?
> It seems completely weird that an existing file with a line commented out have any impact.

It doesn't seem strange to me; maybe we're interpreting wzyboy's data
differently.  The way I read it, if /etc/modprobe.d/iwlwifi.conf
contains "options iwlmvm power_scheme=1", everything works fine (cases
0, 4, 8).  If iwlwifi.conf does not exist or contains only a
commented-out line, he sees problems (cases 2, 6).

> Can you please send the output of:
>         cat /sys/module/iwlmvm/parameters/power_scheme
> in both cases.
>
> Also - what code base are you using?
> Since  this is surely not related to PCI, please remove them in your reply.
> (I keep them here to have them see my mail :))

Agreed, this doesn't sound PCI-related, so I removed linux-pci.  Feel
free to keep me or add me back if you do see anything PCI-related.

Bjorn