Xenial update to 4.4.125 stable release

[Juerg Haefliger]

SRU Justification

Impact:
   The upstream process for stable tree updates is quite similar
   in scope to the Ubuntu SRU process, e.g., each patch has to
   demonstrably fix a bug, and each patch is vetted by upstream
   by originating either directly from a mainline/stable Linux tree
   or a minimally backported form of that patch. The 4.4.125 upstream
   stable stable patch set is now available. It should be included
   in the Ubuntu kernel as well.

   git://git.kernel.org/

TEST CASE: TBD

   The following patches from the 4.4.125 stable release shall be
   applied:

   * Linux 4.4.125
   * bpf, x64: increase number of passes
   * bpf: skip unnecessary capability check
   * kbuild: disable clang's default use of -fmerge-all-constants
   * staging: lustre: ptlrpc: kfree used instead of kvfree
   * perf/x86/intel: Don't accidentally clear high bits in bdw_limit_period()
   * x86/entry/64: Don't use IST entry for #BP stack
   * x86/boot/64: Verify alignment of the LOAD segment
   * x86/build/64: Force the linker to use 2MB page size
   * kvm/x86: fix icebp instruction handling
   * tty: vt: fix up tabstops properly
   * can: cc770: Fix use after free in cc770_tx_interrupt()
   * can: cc770: Fix queue stall & dropped RTR reply
   * can: cc770: Fix stalls on rt-linux, remove redundant IRQ ack
   * staging: ncpfs: memory corruption in ncp_read_kernel()
   * mtd: nand: fsl_ifc: Fix nand waitfunc return value
   * tracing: probeevent: Fix to support minus offset from symbol
   * rtlwifi: rtl8723be: Fix loss of signal
   * brcmfmac: fix P2P_DEVICE ethernet address generation
   * acpi, numa: fix pxm to online numa node associations
   * drm: udl: Properly check framebuffer mmap offsets
   * drm/radeon: Don't turn off DP sink when disconnected
   * drm/vmwgfx: Fix a destoy-while-held mutex problem.
   * x86/mm: implement free pmd/pte page interfaces
   * mm/vmalloc: add interfaces to free unmapped page table
   * libata: Modify quirks for MX100 to limit NCQ_TRIM quirk to MU01 version
   * libata: Make Crucial BX100 500GB LPM quirk apply to all firmware versions
   * libata: Apply NOLPM quirk to Crucial M500 480 and 960GB SSDs
   * libata: Enable queued TRIM for Samsung SSD 860
   * libata: disable LPM for Crucial BX100 SSD 500GB drive
   * libata: Apply NOLPM quirk to Crucial MX100 512GB SSDs
   * libata: remove WARN() for DMA or PIO command without data
   * libata: fix length validation of ATAPI-relayed SCSI commands
   * Bluetooth: btusb: Fix quirk for Atheros 1525/QCA6174
   * clk: bcm2835: Protect sections updating shared registers
   * ahci: Add PCI-id for the Highpoint Rocketraid 644L card
   * PCI: Add function 1 DMA alias quirk for Highpoint RocketRAID 644L
   * mmc: dw_mmc: fix falling from idmac to PIO mode when dw_mci_reset occurs
   * ALSA: hda/realtek - Always immediately update mute LED with pin VREF
   * ALSA: aloop: Fix access to not-yet-ready substream via cable
   * ALSA: aloop: Sync stale timer before release
   * ALSA: usb-audio: Fix parsing descriptor of UAC2 processing unit
   * iio: st_pressure: st_accel: pass correct platform data to init
   * MIPS: ralink: Remove ralink_halt()

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 4.4.0-127.153

---------------
linux (4.4.0-127.153) xenial; urgency=medium

  * CVE-2018-3639 (powerpc)
    - powerpc/pseries: Support firmware disable of RFI flush
    - powerpc/powernv: Support firmware disable of RFI flush
    - powerpc/rfi-flush: Move the logic to avoid a redo into the debugfs code
    - powerpc/rfi-flush: Make it possible to call setup_rfi_flush() again
    - powerpc/rfi-flush: Always enable fallback flush on pseries
    - powerpc/rfi-flush: Differentiate enabled and patched flush types
    - powerpc/rfi-flush: Call setup_rfi_flush() after LPM migration
    - powerpc/pseries: Add new H_GET_CPU_CHARACTERISTICS flags
    - powerpc: Add security feature flags for Spectre/Meltdown
    - powerpc/pseries: Set or clear security feature flags
    - powerpc/powernv: Set or clear security feature flags
    - powerpc/64s: Move cpu_show_meltdown()
    - powerpc/64s: Enhance the information in cpu_show_meltdown()
    - powerpc/powernv: Use the security flags in pnv_setup_rfi_flush()
    - powerpc/pseries: Use the security flags in pseries_setup_rfi_flush()
    - powerpc/64s: Wire up cpu_show_spectre_v1()
    - powerpc/64s: Wire up cpu_show_spectre_v2()
    - powerpc/pseries: Fix clearing of security feature flags
    - powerpc: Move default security feature flags
    - powerpc/pseries: Restore default security feature flags on setup
    - SAUCE: powerpc/64s: Add support for a store forwarding barrier at kernel
      entry/exit

  * CVE-2018-3639 (x86)
    - SAUCE: Clean up IBPB and IBRS control functions and macros
    - SAUCE: Fix up IBPB and IBRS kernel parameters documentation
    - SAUCE: Remove #define X86_FEATURE_PTI
    - x86/cpufeature: Move some of the scattered feature bits to x86_capability
    - x86/cpufeature: Cleanup get_cpu_cap()
    - x86/cpu: Probe CPUID leaf 6 even when cpuid_level == 6
    - x86/cpufeatures: Add CPUID_7_EDX CPUID leaf
    - x86/cpufeatures: Add Intel feature bits for Speculation Control
    - SAUCE: x86/kvm: Expose SPEC_CTRL from the leaf
    - x86/cpufeatures: Add AMD feature bits for Speculation Control
    - x86/msr: Add definitions for new speculation control MSRs
    - SAUCE: x86/msr: Rename MSR spec control feature bits
    - x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown
    - x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes
    - x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support
    - x86/speculation: Add <asm/msr-index.h> dependency
    - x86/cpufeatures: Clean up Spectre v2 related CPUID flags
    - x86/cpuid: Fix up "virtual" IBRS/IBPB/STIBP feature bits on Intel
    - SAUCE: x86/speculation: Move vendor specific IBRS/IBPB control code
    - SAUCE: x86: Add alternative_msr_write
    - SAUCE: x86/nospec: Simplify alternative_msr_write()
    - SAUCE: x86/bugs: Concentrate bug detection into a separate function
    - SAUCE: x86/bugs: Concentrate bug reporting into a separate function
    - arch: Introduce post-init read-only memory
    - SAUCE: x86/bugs: Read SPEC_CTRL MSR during boot and re-use reserved bits
    - SAUCE: x86/bugs, KVM: Support the combination of guest a...