diff --git a/.github/workflows/qemu.yml b/.github/workflows/qemu.yml
index d4ed10fe..c49b4909 100644
--- a/.github/workflows/qemu.yml
+++ b/.github/workflows/qemu.yml
@@ -47,12 +47,12 @@ jobs:
             mirror-state
           key: cache-${{ hashFiles('steps/*/sources') }}
       - name: Run bootstrap
-        run: sudo ./rootfs.py --qemu --external-sources --cores 2 --mirror file://${PWD}/mirror
+        run: sudo ./rootfs.py --qemu --external-sources --cores 1 --mirror file://${PWD}/mirror
       - name: Remount package disk
         if: always()
         run: >
           DEV=$(sudo losetup -f --show target/external.img) &&
-          sudo partprobe ${DEV}p1 &&
+          sudo partprobe ${DEV} &&
           mkdir -p mnt &&
           sudo mount ${DEV}p1 mnt
       - name: Archive created packages