[INFO] updating cached repository https://github.com/tikv/tikv
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] [stderr] From https://github.com/tikv/tikv
[INFO] [stderr]    38e8e07b..50139edd  master      -> master
[INFO] [stderr]    61465d91..c20a85d6  release-3.1 -> release-3.1
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 50139edd79ac60bd9ee95f1630b227d76c5a26b5
[ERROR] this task or one of its parent failed!
[ERROR] command `"/workspace/cargo-home/bin/cargo" "+beta-2019-10-27" "fetch" "--locked" "--manifest-path" "Cargo.toml"` failed
[ERROR] note: run with `RUST_BACKTRACE=1` to display a backtrace.