Comment 4 for bug 1737786

Note: it really isn't suspended as after a while the guest console shows:
[ 606.312026] INFO: task pm-suspend:1258 blocked for more than 120 seconds.
[ 606.316500] Not tainted 4.13.0-19-generic #22-Ubuntu
[ 606.320080] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 606.325221] pm-suspend D 0 1258 1257 0x00000008
[ 606.328838] Call trace:
[ 606.330434] [<ffff000008086020>] __switch_to+0x98/0xb0
[ 606.333873] [<ffff000008a7e748>] __schedule+0x288/0x8d8
[ 606.337347] [<ffff000008a7edc4>] schedule+0x2c/0x88
[ 606.340563] [<ffff0000081313b0>] suspend_devices_and_enter+0x530/0x888
[ 606.344846] [<ffff000008131b9c>] pm_suspend+0x494/0x628
[ 606.348267] [<ffff00000812fef0>] state_store+0x90/0x110
[ 606.351663] [<ffff000008a6df2c>] kobj_attr_store+0x14/0x28
[ 606.355393] [<ffff000008358cf0>] sysfs_kf_write+0x58/0x80
[ 606.359036] [<ffff000008357e20>] kernfs_fop_write+0xe0/0x1f8
[ 606.362854] [<ffff0000082bad40>] __vfs_write+0x48/0x80
[ 606.366315] [<ffff0000082bc2ec>] vfs_write+0xa4/0x1a8
[ 606.369691] [<ffff0000082bdb0c>] SyS_write+0x6c/0xd8
[ 606.372973] [<ffff000008083930>] el0_svc_naked+0x24/0x28

So we see it hangs on the switch_to idle but should on that be gone to sleep.