find_extra_block_devs reads the runner's current extra disks with
`lsblk ... | egrep -v "($boot_dev|loop|nbd)"` to decide how many more to
provision. When the runner has no extra disk, that egrep matches nothing
and exits 1; under the script's `set -eo pipefail` the assignment aborts
the function before it ever calls create_extra_disk, so callers get zero
disks and fail with "expected >= N extra disks, found 0" (or a bare /dev/
path) on those runners.
Guard that first read with `|| true` (as the adjacent device-count line
already is) so an empty result means "no extra disks yet" and the
provisioning path runs. The second read, after create_extra_disk, is left
strict on purpose: if provisioning produced no disk, egrep's non-zero exit
should abort there rather than silently return nothing.
Signed-off-by: Joshua Hoblitt <josh@hoblitt.com>
Joshua Hoblitt
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