I don't expect it helps your boot issue, but the UBSAN issue will be fixed by this commit.
https://<email address hidden>/T/#me31ff6b88640b03be1a8edfc6fc8878ac78ca6bb
Please redo the test with 5.15.
I don't expect it helps your boot issue, but the UBSAN issue will be fixed by this commit.
https://<email address hidden> /T/#me31ff6b886 40b03be1a8edfc6 fc8878ac78ca6bb
Please redo the test with 5.15.