[APL][SAUCE] Slow system response time due to a monitor bug

[Phidias]

[Impact]

We've found a bug on some Apollo Lake system makes it runs very slow. From upstream it is caused by following reason:

"Monitored cached line may not wake up from mwait on certain Goldmont based CPUs. This patch will avoid calling current_set_polling_and_test() and thereby not set the TIF_ flag. The result is that we'll always send IPIs for wakeups."

[Fix]

Upstream already provided a workaround[1] to fix this problem. This patches haven't been merged in latest(v4.7) release but already in linux-next.

To fix this issue in Xenial it also needs another commit introduces macros use in the workaround:

commit 970442c599b22ccd644ebfe94d1d303bf6f87c05
Author: Dave Hansen <email address hidden>
Date: Thu Jun 2 17:19:27 2016 -0700

    x86/cpu/intel: Introduce macros for Intel family numbers

This workaround checks CPU families and certain features, so no further regressions is expected

[1]: https://lkml.org/lkml/2016/7/6/469

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1606147

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.

[Seth Forshee (sforshee)]

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 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 - 4.4.0-34.53

---------------
linux (4.4.0-34.53) xenial; urgency=low

  [ Seth Forshee ]

  * Release Tracking Bug
    - LP: #1606960

  * [APL][SAUCE] Slow system response time due to a monitor bug (LP: #1606147)
    - x86/cpu/intel: Introduce macros for Intel family numbers
    - SAUCE: x86/cpu: Add workaround for MONITOR instruction erratum on Goldmont
      based CPUs

linux (4.4.0-33.52) xenial; urgency=low

  [ Seth Forshee ]

  * Release Tracking Bug
    - LP: #1605709

  * [regression] NFS client: access problems after updating to kernel
    4.4.0-31-generic (LP: #1603719)
    - SAUCE: (namespace) Bypass sget() capability check for nfs

linux (4.4.0-32.51) xenial; urgency=low

  [ Seth Forshee ]

  * Release Tracking Bug
    - LP: #1604443

  * thinkpad yoga 260 wacom touchscreen not working (LP: #1603975)
    - HID: wacom: break out parsing of device and registering of input
    - HID: wacom: Initialize hid_data.inputmode to -1
    - HID: wacom: Support switching from vendor-defined device mode on G9 and G11

  * changelog: add CVEs as first class citizens (LP: #1604344)
    - use CVE numbers in changelog

  * [Xenial] Include Huawei PCIe SSD hio kernel driver (LP: #1603483)
    - SAUCE: import Huawei ES3000_V2 (2.1.0.23)
    - SAUCE: hio: bio_endio() no longer takes errors arg
    - SAUCE: hio: blk_queue make_request_fn now returns a blk_qc_t
    - SAUCE: hio: use alloc_cpumask_var to avoid -Wframe-larger-than
    - SAUCE: hio: fix mask maybe-uninitialized warning
    - [config] enable CONFIG_HIO (Huawei ES3000_V2 PCIe SSD driver)
    - SAUCE: hio: Makefile and Kconfig

  * CVE-2016-5243 (LP: #1589036)
    - tipc: fix an infoleak in tipc_nl_compat_link_dump
    - tipc: fix nl compat regression for link statistics

  * CVE-2016-4470
    - KEYS: potential uninitialized variable

  * integer overflow in xt_alloc_table_info (LP: #1555353)
    - netfilter: x_tables: check for size overflow

  * CVE-2016-3135:
    - Revert "UBUNTU: SAUCE: (noup) netfilter: x_tables: check for size overflow"

  * CVE-2016-4440 (LP: #1584192)
    - kvm:vmx: more complete state update on APICv on/off

  * the system hangs in the dma driver when reboot or shutdown on a baytrail-m
    laptop (LP: #1602579)
    - dmaengine: dw: platform: power on device on shutdown
    - ACPI / LPSS: override power state for LPSS DMA device

  * Add proper palm detection support for MS Precision Touchpad (LP: #1593124)
    - Revert "HID: multitouch: enable palm rejection if device implements
      confidence usage"
    - HID: multitouch: enable palm rejection for Windows Precision Touchpad

  * Add support for Intel 8265 Bluetooth ([8087:0A2B]) (LP: #1599068)
    - Bluetooth: Add support for Intel Bluetooth device 8265 [8087:0a2b]

  * CVE-2016-4794 (LP: #1581871)
    - percpu: fix synchronization between chunk->map_extend_work and chunk
      destruction
    - percpu: fix synchronization between synchronous map extension and chunk
      destruction

  * Xenial update to v4.4.15 stable release (LP: #1601952)
    - net_sched: fix pfifo_head_drop behavior vs backlog
    - net: Don't forget pr_fmt on net_dbg_ratelimited for CONFIG_DYNAMIC...