This tests continue failing on CFL QA
the test hanging before finish, only partial results are gotten...

igt@gem_exec_whisper@hang-forked

====================================================
Full output 
====================================================
IGT-Version: 1.20-gc0be331 (x86_64) (Linux: 4.15.0-rc4-drm-intel-qa-ww51-commit-bf5cdf9+ x86_64)
(gem_exec_whisper:1833) drmtest-DEBUG: Test requirement passed: !(fd<0)
(gem_exec_whisper:1833) igt-debugfs-DEBUG: Opening debugfs directory '/sys/kernel/debug/dri/0'
(gem_exec_whisper:1833) drmtest-DEBUG: Test requirement passed: is_i915_device(fd) && has_known_intel_chipset(fd)
(gem_exec_whisper:1833) ioctl-wrappers-DEBUG: Test requirement passed: err == 0
(gem_exec_whisper:1833) DEBUG: Test requirement passed: gem_can_store_dword(fd, 0)
Using GuC submission
(gem_exec_whisper:1833) igt-core-DEBUG: Starting subtest: hang-forked
(gem_exec_whisper:1833) igt-debugfs-DEBUG: Opening debugfs directory '/sys/kernel/debug/dri/0'
(gem_exec_whisper:1833) DEBUG: Test requirement passed: nengine
(gem_exec_whisper:1833) drmtest-DEBUG: Test requirement passed: !(fd<0)
(gem_exec_whisper:1833) i915/gem-context-DEBUG: Test requirement passed: has_ban_period || has_bannable
(gem_exec_whisper:1833) igt-gt-DEBUG: Test requirement passed: has_gpu_reset(fd)
(gem_exec_whisper:1833) igt-debugfs-DEBUG: Opening debugfs directory '/sys/kernel/debug/dri/0'
(gem_exec_whisper:1833) igt-debugfs-DEBUG: Opening debugfs directory '/sys/kernel/debug/dri/0'

This is my configuration:
======================================
	Graphic stack
======================================
Component: drm
    tag: libdrm-2.4.88-42-g831036a
    commit: 831036a6f62005da9fb4a75fe043bd96ce672d27

Component: cairo
    tag: 1.15.8-73-g903b0de
    commit: 903b0de539844c144c63ea57c30e84a23360c290

Component: intel-gpu-tools
    tag: intel-gpu-tools-1.20-232-gc0be331
    commit: c0be3310715e2f744b892c51f09e62273bcc8e57

Component: piglit
    tag: piglit-v1
    commit: 64775cc0f59820c4d733e480a66f8c31f5b78d1b

======================================
	     Software
======================================
kernel version              : 4.15.0-rc4-drm-intel-qa-ww51-commit-bf5cdf9+
hostname                    : CFL-1
architecture                : x86_64
os version                  : Ubuntu 16.10
os codename                 : yakkety
kernel driver               : i915
bios revision               : 104.3
bios release date           : 09/14/2017
ksc                         : 1.5
hardware acceleration       : disabled
swap partition              : enabled on (/dev/nvme0n1p3)

======================================
	Graphic drivers
======================================
libdrm                      : 2.4.89
cairo                       : 1.15.11
intel-gpu-tools (tag)       : intel-gpu-tools-1.20-232-gc0be331
intel-gpu-tools (commit)    : c0be331

======================================
	     Hardware
======================================
motherboard model          : CoffeeLakeClientPlatform
motherboard id             : CoffeeLakeSUDIMMRVP
form factor                : Desktop
manufacturer               : IntelCorporation
cpu family                 : Other
cpu family id              : 6
cpu information            : Genuine Intel(R) CPU 0000 @ 3.60GHz
gpu card                   : Intel Corporation Device 3e92 (prog-if 00 [VGA controller])
memory ram                 : 15.58 GB
max memory ram             : 32 GB
cpu thread                 : 12
cpu core                   : 6
cpu model                  : 158
cpu stepping               : 10
socket                     : Other
current cd clock frequency : 337500 kHz
maximum cd clock frequency : 675000 kHz
displays connected         : eDP-1 DP-1

======================================
	     Firmware
======================================
dmc fw loaded             : yes
dmc version               : 1.4
guc fw loaded             : fetch SUCCESS, load SUCCESS
guc version wanted        : wanted 9.39, found 9.39
guc version found         : wanted 9.39, found 9.39

======================================
	     kernel parameters
======================================
quiet drm.debug=0x1e i915.enable_guc=-1 i915.alpha_support=1 auto panic=1 nmi_watchdog=panic intel_iommu=igfx_off resume=/dev/nvme0n1p3 fastboot

Created attachment 136260 [details]
kernel log

Created attachment 136261 [details]
otuput (incomplete...)

Created attachment 136262 [details]
dmesg -w

There's no indication of any failure here. The test takes about 4 days to run.