Check to see if ZFS is available before invoking bectl

[gordon]

Summary

bectl will unconditionally load the ZFS module. For systems not running ZFS, we shouldn't be spuriously loading ZFS just because we ran freebsd-update install.

[kevans]

We have a fix for this already in the tree; bectl/libbe was never meant to trigger loading of zfs.ko in the first place.

• main: 2f700ca965a04c4a03b6f760da6a210b6ca4df4b
• stable/13: f25a4bbf5d1ff31708d64f9cca644ae34e62cab0

We could bring it back to stable/12, too, if we need to... it's been soaking for quite a while.

[kevans]

In D42449#968665, @kevans wrote:

We have a fix for this already in the tree; bectl/libbe was never meant to trigger loading of zfs.ko in the first place.

• main: 2f700ca965a04c4a03b6f760da6a210b6ca4df4b
• stable/13: f25a4bbf5d1ff31708d64f9cca644ae34e62cab0

We could bring it back to stable/12, too, if we need to... it's been soaking for quite a while.

I went ahead and tested it on and brought it back to stable/12 in case you're trying to errata this or something...

• stable/12: ee4bdd4b0db5b9d64e64490fc84a395344862aed

[gordon]

I mostly just noticed this on a fresh UFS based install. Do you think it would be good to have both checks (one in bectl and one in freebsd-update)?

[kevans]

In D42449#968786, @gordon wrote:

I mostly just noticed this on a fresh UFS based install. Do you think it would be good to have both checks (one in bectl and one in freebsd-update)?

IMO no since this was really anomalous behavior, but I'd grab a second opinion from our resident freebsd-update expert @emaste to be sure...