iwlwifi driver exports all packets through netlink

[Alfredo Matos]

A new option present in Kernel 3.0 enables exporting all wifi packets on the iwlwifi driver through (generic) netlink, for debug purposes (an intel undisclosed svtool). This should not be enabled by default, as it forces all wifi packet to be delivered through netlink (causing a large amount of netlink operations, leading to cpu overhead, and battery overhead).

The offending option is:
CONFIG_IWLWIFI_DEVICE_SVTOOL=y

This should be disabled in production systems, as it only matters for development/testing.

[Leann Ogasawara (leannogasawara)]

Hi Alfredo,

I've posted a test kernel with CONFIG_IWLWIFI_DEVICE_SVTOOL disabled (ie =n) at the following location. Please test and let me know your results. Thanks.

http://people.canonical.com/~ogasawara/lp819925/

[Alfredo Matos (alfmatos)]

I've tested it, and it indeed the kernel you shared packets are not transferred over the netlink interface. I would just point out that you shared a 2.6.39, while oneiric is on 3.0 :).

[Leann Ogasawara (leannogasawara)]

Hrm, that test kernel version does look a bit odd. Can you retest with the newer test kernel I've just placed at the same location just so we can be sure. I apologize for the inconvenience. Thanks!

http://people.canonical.com/~ogasawara/lp819925/

[Alfredo Matos (alfmatos)]

I can confirm that this fixes the problem. I'm not seeing anymore packets being transferred to userspace!

[Leann Ogasawara (leannogasawara)]

Thanks, I've queued this patch for the next Oneiric kernel upload. Marking this Fix Committed. Thanks!

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 3.0.0-8.10

---------------
linux (3.0.0-8.10) oneiric; urgency=low

  [ Adam Jackson ]

  * SAUCE: drm/i915/pch: Fix integer math bugs in panel fitting
    - LP: #753994

  [ John Johansen ]

  * [Config] Enable missing IPv6 options

  [ Leann Ogasawara ]

  * [Config] Disable config IWLWIFI_DEVICE_SVTOOL
    - LP: #819925
  * Rebase to 3.0.1

  [ Upstream Kernel Changes ]

  * x86, intel, power: Correct the MSR_IA32_ENERGY_PERF_BIAS message
  * ALSA: hda - Turn on extra EAPDs on Conexant codecs
    - LP: #783582
  * KVM: Remove SMEP bit from CR4_RESERVED_BITS
    - LP: #796476
  * KVM: Add SMEP support when setting CR4
    - LP: #796476
  * KVM: Mask function7 ebx against host capability word9
    - LP: #796476
  * KVM: Add instruction fetch checking when walking guest page table
    - LP: #796476

  [ Upstream Kernel Changes ]

  * rebase to v3.0.1
 -- Leann Ogasawara <email address hidden> Fri, 05 Aug 2011 11:32:25 -0700