$ git clone -n https://src.fedoraproject.org/rpms/perl-Sys-Virt.git /var/lib/mock/f41-build-817023-150574/root/chroot_tmpdir/scmroot/perl-Sys-Virt
Cloning into '/var/lib/mock/f41-build-817023-150574/root/chroot_tmpdir/scmroot/perl-Sys-Virt'...
$ git fetch origin 919fba1d1f7002d6eeb0d2fed4e89be0224cc8ff:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Sys-Virt
 * [new ref]         919fba1d1f7002d6eeb0d2fed4e89be0224cc8ff -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 919fba1 Perl 5.40 rebuild