Re: 3bf53c4c8f53 - main - release(7): Enable zpoolupgrade rc script in ZFS based VM images

Hi Li-Wen,

If I'm reading this (and 72a1cb05cd23) correctly, this will run `zpool upgrade' on the "zroot" pool on every boot. That's fine for the first time a VM image is used, since presumably the root pool and the bootloader were generated from the same sources. But if the root pool is subsequently upgraded by the running VM, don't we need to make sure the bootloader is also upgraded? Otherwise, don't we run into the possibility of this new `zpoolupgrade' script enabling features which are not supported by the bootloader?

There should be some mechanism for upgrading the bootloader, or else something else that runs on the first boot from the VM image should disable `zpoolupgrade' so it is only run the first time.

Thanks,

Ravi (rpokala@)

-----Original Message-----
From: <owner-src-committers@freebsd.org> on behalf of Li-Wen Hsu <lwhsu@FreeBSD.org>
Date: 2022-11-06, Sunday at 19:50
To: <src-committers@FreeBSD.org>, <dev-commits-src-all@FreeBSD.org>, <dev-commits-src-main@FreeBSD.org>
Subject: git: 3bf53c4c8f53 - main - release(7): Enable zpoolupgrade rc script in ZFS based VM images

    The branch main has been updated by lwhsu:

    URL: https://cgit.FreeBSD.org/src/commit/?id=3bf53c4c8f53b1f19313e9c31415c7eee830cdc0

    commit 3bf53c4c8f53b1f19313e9c31415c7eee830cdc0
    Author:     Li-Wen Hsu <lwhsu@FreeBSD.org>
    AuthorDate: 2022-11-07 03:47:33 +0000
    Commit:     Li-Wen Hsu <lwhsu@FreeBSD.org>
    CommitDate: 2022-11-07 03:47:33 +0000

        release(7): Enable zpoolupgrade rc script in ZFS based VM images

        This will enable VM access to all ZFS feature automatically, only on a
        newly installed or provisioned VM or cloud instance.

        Reviewed by:    markj
        Sponsored by:   The FreeBSD Foundation
        Differential Revision: https://reviews.freebsd.org/D37283
    ---
     release/tools/vmimage.subr | 1 +
     1 file changed, 1 insertion(+)

    diff --git a/release/tools/vmimage.subr b/release/tools/vmimage.subr
    index 8982e768527a..a65ec4f1a1f9 100644
    --- a/release/tools/vmimage.subr
    +++ b/release/tools/vmimage.subr
    @@ -83,6 +83,7 @@ vm_install_base() {
     	if [ "${VMFS}" = zfs ]; then
     		echo "zfs_enable=\"YES\"" >> ${DESTDIR}/etc/rc.conf
     		echo "zpool_reguid=\"zroot\"" >> ${DESTDIR}/etc/rc.conf
    +		echo "zpool_upgrade=\"zroot\"" >> ${DESTDIR}/etc/rc.conf
     	fi

     	if ! [ -z "${QEMUSTATIC}" ]; then