$ git clone -n https://gitee.com/gcdota930915/grub2.git /var/lib/mock/dist-an23-build-548554-87880/root/chroot_tmpdir/scmroot/grub2
Cloning into '/var/lib/mock/dist-an23-build-548554-87880/root/chroot_tmpdir/scmroot/grub2'...
$ git fetch origin 70b833b814bda4c9927e0ab45840e6060832f6b9:KOJI_FETCH_HEAD
From https://gitee.com/gcdota930915/grub2
 * [new ref]         70b833b814bda4c9927e0ab45840e6060832f6b9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 70b833b Backport upstream 569214e2: fix GRUB ext2 driver misreading ext4 external extent tree (>4 extents)