grub2: Generate config from pending deployment

[rfairley]

Attempt at a fix for #1774. Previously pushed these changes (see #1774 (comment)) - posting a PR so we can discuss here.

Involves an interface change to add the new_deployments argument to each bootloader *_write_config function. It'd be preferable to avoid passing down the extra argument - but this seems to be what's needed to expose the pending deployment to the bootloader functions.

Need to verify that the tests work (recently updated my dev environment and tests that previously passed are failing locally).

[cgwalters]

Something is going wrong in PAPR I think, but let's get the tests passing. Otherwise besides one minor nit, LGTM!

[rfairley]

Taking a look at the failing CI test, thanks!

[rfairley]

Reworked the test so that it exercises the grub2-mkconfig path where the assertion failed in #1774. To test the grub2-mkconfig code path, I did export OSTREE_GRUB2_EXEC=grub2-mkconfig in the test script.

However, the test runs into error: Bootloader write config: grub2-mkconfig: Child process exited with code 1. Running sudo make check TESTS=tests/test-admin-deploy-grub2.sh on my machine gives a different result: error: Bootloader write config: Failed to execute child process “grub2-mkconfig” (No such file or directory). Applying the following patch allowed the test to pass with sudo on my machine (I think this makes the grub2-mkconfig binary on my host visible to the test):

diff --git a/src/libostree/ostree-bootloader-grub2.c b/src/libostree/ostree-bootloader-grub2.c
index 1e5791d65..7feba43a2 100644
--- a/src/libostree/ostree-bootloader-grub2.c
+++ b/src/libostree/ostree-bootloader-grub2.c
@@ -321,7 +321,7 @@ grub2_child_setup (gpointer user_data)
       _exit (1);
     }
 
-  if (chroot (".") != 0)
+  if (chroot ("/") != 0)
     {
       perror ("chroot");
       _exit (1);

Manually testing in Fedora Atomic Host 29 with mkdir sysroot && ostree admin init-fs sysroot && ostree pull-local --repo=sysroot/ostree/repo /sysroot/ostree/repo rpmostree/base/0 && ostree admin os-init osname --sysroot sysroot && ref=$(ostree refs --repo sysroot/ostree/repo) && mkdir -p sysroot/boot/grub2 && touch sysroot/boot/grub2/grub.cfg && ostree admin deploy "$ref" --sysroot sysroot --os osname -v 2>err.txt, the deploy is successful with:

Transaction complete; bootconfig swap: yes; deployment count change: 1

(previously the above command hit the assertion in #1774).

The tests in tests/admin-test.sh also pass.

To have the test run grub2-mkconfig without sudo and without the patch above, could bwrap be used for this? (seeing this comment

ostree/src/libostree/ostree-bootloader-grub2.c

Line 293 in 5fd06d6

/* TODO: investigate replacing this with bwrap */

). Thinking it would work by binding in a grub2-mkconfig installed on the host running the test.

Considering manually testing the changes here works though, would the libostree changes be OK to merge and then the automated test can be dealt with separately?

Also see there is some history here: https://bugzilla.gnome.org/show_bug.cgi?id=761180

[rfairley]

For now I just removed the auto test - as it seems the grub2-mkconfig binary would need to be present in order to test the code path changed here (to make sure the assertion doesn't fail). Not sure of a way to run this in the test suite (needed the hacks 1) the patch in this comment, and 2) run the test suite as sudo, to get it to work on my machine).

This is the test trying to exercise grub2-mkconfig - in case we come back to this:

diff --git a/tests/test-admin-deploy-grub2.sh b/tests/test-admin-deploy-grub2.sh
index 231aa2f8..f3e2180a 100755
--- a/tests/test-admin-deploy-grub2.sh
+++ b/tests/test-admin-deploy-grub2.sh
@@ -26,6 +26,21 @@ set -euo pipefail
 # Exports OSTREE_SYSROOT so --sysroot not needed.
 setup_os_repository "archive" "grub2 ostree-grub-generator"
 
-extra_admin_tests=0
+extra_admin_tests=1
 
 . $(dirname $0)/admin-test.sh
+
+# Check that deploying a new tree with zero previous deployments works.
+# (see https://github.com/ostreedev/ostree/issues/1774).
+cd ${test_tmpdir}
+rm httpd osdata testos-repo sysroot -rf
+setup_os_repository "archive" "grub2"
+# Exercise the system grub2-mkconfig codepath.
+export OSTREE_GRUB2_EXEC=grub2-mkconfig
+${CMD_PREFIX} ostree pull-local --repo=sysroot/ostree/repo --remote testos testos-repo testos/buildmaster/x86_64-runtime
+${CMD_PREFIX} ostree admin deploy --karg=root=LABEL=MOO --karg=quiet --sysroot sysroot --os testos testos/buildmaster/x86_64-runtime > out.txt
+assert_file_has_content out.txt "Transaction complete.*"
+assert_file_has_content sysroot/boot/loader/entries/ostree-1-testos.conf 'options.* root=LABEL=MOO'
+assert_file_has_content sysroot/boot/ostree/testos-${bootcsum}/vmlinuz-3.6.0 'a kernel'
+assert_file_has_content sysroot/boot/ostree/testos-${bootcsum}/initramfs-3.6.0.img 'an initramfs'
+echo "ok run grub2 bootloader on first deployment"

[jlebon]

This looks good to me! Just one super minor/optional nit.

[jlebon]

Thanks!

@rh-atomic-bot r+ dc2f6c0

Re. tests, yeah I don't think there's an easy way to add this to the make check harness right now. Higher-level tests like f28-rpmostree would exercise this, though CI here is in need of an overhaul.

[rh-atomic-bot]

⚡ Test exempted: merge already tested.