pkg/47294: Add support for major version upgrades to sysupgrade

[jmmv%netbsd.org@localhost]

>Number:         47294
>Category:       pkg
>Synopsis:       Add support for major version upgrades to sysupgrade
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Fri Dec 07 16:25:00 +0000 2012
>Originator:     Julio Merino
>Release:        NetBSD 5.1_STABLE
>Organization:
Julio Merino
>Environment:
        
        
System: NetBSD homeworld.netbsd.org 5.1_STABLE NetBSD 5.1_STABLE (NBMAIL) #2: 
Mon Jun 11 07:45:45 UTC 2012 
root%franklin.NetBSD.org@localhost:/home/netbsd/5/amd64/kern-compile/NBMAIL 
amd64
Architecture: x86_64
Machine: amd64
>Description:
        pkgsrc/sysutils/sysupgrade does not currently support upgrades that
        require a reboot between the installation of the new kernel and the
        installation of new sets.  Such upgrades will break half-way through
        because the new installed binaries will stop working until the user
        reboots.  It's not a critical problem, but it certainly is not a good
        procedure.

        The main idea to fix this is to split the upgrade procedure in two
        pieces: before reboot and after reboot, and add some "heuristics" to
        determine if it's safe to do the upgrade without a reboot in between.
        If the upgrade needs a reboot, the user would be asked to reboot the
        machine after the installation of the new kernel/modules, and type
        a new command to resume the upgrade (e.g. "sysupgrade resume").

        Such resume command may come in handy to also continue upgrades that
        break in the middle of the process, as is the case when some
        postinstall checks fail.

        Additionally, provide an optionally-installable rc.d script that can
        detect an "open upgrade" and resume it during system restart, so that
        the user is not required to type anything else after the reboot.
>How-To-Repeat:
        Upgrade from 5.0 to 6.0 using sysupgrade and see the system "explode"
        along the way.
>Fix:
        SMOP.

>Unformatted: