$ git clone -n https://github.com/xcp-ng-rpms/kernel-alt.git /var/lib/mock/v8.1-testing-2090-1521/root/chroot_tmpdir/scmroot/kernel-alt
Cloning into '/var/lib/mock/v8.1-testing-2090-1521/root/chroot_tmpdir/scmroot/kernel-alt'...
$ git reset --hard 54383ebb164d0695fb0e9c1403682e0950eef64c
Downloading SOURCES/kernel-4.19.19.tar.gz (161 MB)
HEAD is now at 54383eb Rename perf to perf-alt and python2-perf to python2-perf-alt