$ git clone -n https://gitee.com/wenyuzifang/llvm.git /var/lib/mock/dist-an23-build-447300-73363/root/chroot_tmpdir/scmroot/llvm
Cloning into '/var/lib/mock/dist-an23-build-447300-73363/root/chroot_tmpdir/scmroot/llvm'...
$ git fetch origin b57667f266e70a6b2a50d9271dc439d1ab7f78b0:KOJI_FETCH_HEAD
From https://gitee.com/wenyuzifang/llvm
 * [new ref]         b57667f266e70a6b2a50d9271dc439d1ab7f78b0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b57667f Update code from upstream