mount: tests lock up with GOMAXPROCS=1 or 2 #3259
Description
As reported in #3154 the test for cmd/mount locks up if GOMAXPROCS=1 or 2
This runs fine
cd ~/go/src/github.com/ncw/rclone/cmd/mount
export GOMAXPROCS=4
( for i in `seq 1000`; do echo `date -Is`: Trial $i ; go test -v -verbose -count=1 ; done ) 2>&1 | tee mount.log
And this locks up almost immediately
export GOMAXPROCS=1
( for i in `seq 1000`; do echo `date -Is`: Trial $i ; go test -v -verbose -count=1 ; done ) 2>&1 | tee mount.log
with
2019-06-12T16:46:56+00:00: Trial 1
=== RUN TestMount
=== RUN TestMount/CacheMode=off
=== RUN TestMount/CacheMode=off/TestTouchAndDelete
Mount is stuck in the kernel at this point making nasty unkillable processes.
The build issue has been worked around by setting GOMAXPROCS but the underlying issue remains.