[issue2039] Sometimes, DragonFly 2.9 systems can not reboot

[Matthew Dillon]

:I have found a reliable way to trigger it:
:switch to single user mode
:mount -a
:cd /usr/src
:make installworld && make upgrade && reboot
:
:print_uptime() has not been called in my case.
:
:Best Regards,
:sephe

    Hmm.  If the uptime is not displayed this implies that the
    vfs_unmountall() call is getting stuck.

    Try with the latest master, I made some adjustments that might effect
    raw device closes.  If swapcache is turned on try turning it off
    (though my latest patch turns it off on shutdown automatically, too).

    So far I cannot replicate the issue on my test box.  I did have
    reboot issues in past related to swapcache but those are gone now
    w/my recent commits.

    Other possible causes: tmpfs, vn, usb mounts, procfs, etc.

    If you can reliably replicate the problem you may have to add a bunch
    of kprintf()'s to the umountall iterator to track down which filesystem
    is getting stuck.  I have included a df of my test box below.

						-Matt


Filesystem                         1K-blocks       Used      Avail Capacity  Mounted on
ROOT                                195452928  64848560  130604368    33%    /
devfs                                       1         1          0   100%    /dev
/dev/serno/L41K2H5G.s1a                774094    216628     495540    30%    /boot
/pfs/@@-1:00001                     195452928  64848560  130604368    33%    /var
/pfs/@@-1:00002                     195452928  64848560  130604368    33%    /tmp
/pfs/@@-1:00003                     195452928  64848560  130604368    33%    /usr
/pfs/@@-1:00004                     195452928  64848560  130604368    33%    /home
/pfs/@@-1:00005                     195452928  64848560  130604368    33%    /usr/obj
/pfs/@@-1:00006                     195452928  64848560  130604368    33%    /var/crash
/pfs/@@-1:00007                     195452928  64848560  130604368    33%    /var/tmp
BUILD                               104398848  42510688   61888160    41%    /build3
procfs                                      4         4          0   100%    /proc
apollo.backplane.com:/usr/src      1934024704 292436496 1641588208    15%    /usr/src
apollo.backplane.com:/usr/src-misc 1934024704 292436496 1641588208    15%    /usr/src-misc
apollo.backplane.com:/usr/pkgsrc   1934024704 292436496 1641588208    15%    /usr/pkgsrc
apollo.backplane.com:/netboot1     1934024704 292436496 1641588208    15%    /netboot1
test29#