These tests run a crosvm VM on the host to verify end to end behavior. They use a prebuilt guest kernel and rootfs, which is downloaded from google cloud storage.
If the test needs to run offline, or you want to make changes to the kernel or rootfs, you have to specify the environment variables CROSVM_CARGO_TEST_KERNEL_BINARY
and CROSVM_CARGO_TEST_ROOTFS_IMAGE
to point to the right files.
The use_local_build.sh script does this for you:
$ source guest_under_test/use_local_build.sh
Note: Only Googlers with access to the crosvm-testing cloud storage bin can upload prebuilts.
To upload the modified rootfs, you will have to uprev the PREBUILT_VERSION
variable in:
./guest_under_test/PREBUILT_VERSION
src/third_party/chromiumos-overlay/chromeos-base/crosvm/crosvm-9999.ebuild
Then run the upload script to build and upload the new prebuilts. Never try to modify an existing prebuilt as the new images may break tests in older versions.