ubuntu/rsi driver downlink wifi throughput drops to 5-6 Mbps when BT keyboard is connected

[Amitkumar Karwar]

SRU Justification
=================

[Impact]
wifi throughput numbers are good when device is running in WLAN only mode.

In STA+BT+BLE mode, we get expected wifi throughput numbers when BT device is not connected. However downlink throughput drops to 5-6 Mbps from 35+Mbps as soon as bluetooth keyboard is connected.

[Fix]
Enable UAPSD mode with some optimized parameters, so that wifi station can get Rx packets buffered by AP efficiently even if radio is shared with bluetooth

[Test Case]
Conducted throughput tests and confirmed throughput gets dropped by 60% to 65% as expected(not more than that) when bluetooth keyboard connected.

[Ubuntu Kernel Bot (ubuntu-kernel-bot)]

This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:

apport-collect 1706991

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Joseph Salisbury (jsalisbury)]

Did this issue start happening after an update/upgrade? Was there a prior kernel version where you were not having this particular problem?

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.13 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.13-rc2

[Amitkumar Karwar (amitkarwar)]

Patches has been posted to ubuntu mailing list to address this issue.
Link: https://lists.ubuntu.com/archives/kernel-team/2017-July/086027.html
      https://lists.ubuntu.com/archives/kernel-team/2017-July/086028.html

[Kleber Sacilotto de Souza (kleber-souza)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-xenial' to 'verification-done-xenial'. If the problem still exists, change the tag 'verification-needed-xenial' to 'verification-failed-xenial'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 4.4.0-93.116

---------------
linux (4.4.0-93.116) xenial; urgency=low

  * linux: 4.4.0-93.116 -proposed tracker (LP: #1709296)

  * Creating conntrack entry failure with kernel 4.4.0-89 (LP: #1709032)
    - Revert "Revert "netfilter: synproxy: fix conntrackd interaction""
    - netfilter: nf_ct_ext: fix possible panic after nf_ct_extend_unregister

  * CVE-2017-1000112
    - Revert "udp: consistently apply ufo or fragmentation"
    - udp: consistently apply ufo or fragmentation

  * CVE-2017-1000111
    - Revert "net-packet: fix race in packet_set_ring on PACKET_RESERVE"
    - packet: fix tp_reserve race in packet_set_ring

  * kernel BUG at [tty_ldisc_reinit] mm/slub.c! (LP: #1709126)
    - tty: Simplify tty_set_ldisc() exit handling
    - tty: Reset c_line from driver's init_termios
    - tty: Handle NULL tty->ldisc
    - tty: Move tty_ldisc_kill()
    - tty: Use 'disc' for line discipline index name
    - tty: Refactor tty_ldisc_reinit() for reuse
    - tty: Destroy ldisc instance on hangup

  * atheros bt failed after S3 (LP: #1706833)
    - SAUCE: Bluetooth: Make request workqueue freezable

  * The Precision Touchpad(PTP) button sends incorrect event code (LP: #1708372)
    - HID: multitouch: handle external buttons for Precision Touchpads

  * Set CONFIG_SATA_HIGHBANK=y on armhf (LP: #1703430)
    - [Config] CONFIG_SATA_HIGHBANK=y

  * xfs slab objects (memory) leak when xfs shutdown is called (LP: #1706132)
    - xfs: fix xfs_log_ticket leak in xfs_end_io() after fs shutdown

  * Adt tests of src:linux time out often on armhf lxc containers (LP: #1705495)
    - [Packaging] tests -- reduce rebuild test to one flavour

  * CVE-2017-7495
    - ext4: fix data exposure after a crash

  * ubuntu/rsi driver downlink wifi throughput drops to 5-6 Mbps when BT
    keyboard is connected (LP: #1706991)
    - SAUCE: Redpine: enable power save by default for coex mode
    - SAUCE: Redpine: uapsd configuration changes

  * [Hyper-V] hv_netvsc: Exclude non-TCP port numbers from vRSS hashing
    (LP: #1690174)
    - hv_netvsc: Exclude non-TCP port numbers from vRSS hashing

  * ath10k doesn't report full RSSI information (LP: #1706531)
    - ath10k: add per chain RSSI reporting

  * ideapad_laptop don't support v310-14isk (LP: #1705378)
    - platform/x86: ideapad-laptop: Add several models to no_hw_rfkill

  * [8087:0a2b] Failed to load bluetooth firmware(might affect some other Intel
    bt devices) (LP: #1705633)
    - Bluetooth: btintel: Create common Intel Version Read function
    - Bluetooth: Use switch statement for Intel hardware variants
    - Bluetooth: Replace constant hw_variant from Intel Bluetooth firmware
      filename
    - Bluetooth: hci_intel: Fix firmware file name to use hw_variant
    - Bluetooth: btintel: Add MODULE_FIRMWARE entries for iBT 3.5 controllers

  * xhci_hcd: ERROR Transfer event TRB DMA ptr not part of current TD ep_index 2
    comp_code 13 (LP: #1667750)
    - xhci: Bad Ethernet performance plugged in ASM1042A host

  * OpenPower: Some multipaths temporarily have only a single path
    (LP: #1696445)
    - scsi: ses: don't get power status of SES device slot on probe

  ...

[Timo Aaltonen (tjaalton)]

This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-bionic' to 'verification-done-bionic'. If the problem still exists, change the tag 'verification-needed-bionic' to 'verification-failed-bionic'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

[Andy Whitcroft (apw)]

This bug was erroneously marked for verification in bionic; verification is not required and verification-needed-bionic is being removed.