validation/mounts.t fails with several mount points test failures, such as

not ok 11 - mounts[6] (/tmp) found

Inside the runc container, /proc/self/mountinfo shows a corresponding entry:

296 279 0:67 / /tmp rw,nosuid - tmpfs /home/dpark/go/src/github.com/opencontainers/runc/tmpfs rw,size=65536k,mode=755

Here the absolute path /home/dpark/go/src/github.com/opencontainers/runc/tmpfs is interpreted to "mount source", which does not seem to be actually meaningful in this case. However the runtime-tools validation test fails because cmd/runtimetest/main.go strictly checks if the given mount source is equal to an expected mount source. That's why the validation test fails.

On the other hand, runtime-spec says that mount source is optional, since opencontainers/runtime-spec#699 was merged. So can we just remove the check in cmd/runtimetest/main.go?