Commit Graph

3 Commits

Author SHA1 Message Date
Rudd-O b0f578a807 Use a different technique to detect whether to mount-zfs
The behavior of the Dracut module was very wrong before.

The correct behavior: initramfs should not run `zfs-mount` to completion
if the two generator files exist.  If, however, one of them is missing,
it indicates one of three cases:

* The kernel command line did not specify a root ZFS file system, and
  another Dracut module is already handling root mount (via systemd).
  `mount-zfs` can run, but it will do nothing.
* There is no systemd to run `sysroot.mount` to begin with.
  `mount-zfs` must run.
* The root parameter is zfs:AUTO, which cannot be run in sysroot.mount.
  `mount-zfs` must run.

In any of these three cases, it is safe to run `zfs-mount` to completion.

`zfs-mount` must also delete itself if it determines it should not run,
or else Dracut will do the insane thing of running it over and over again.
Literally, the definition of insanity, doing the same thing that did not
work before, expecting different results.  Doing that may have had a great
result before, when we had a race between devices appearing and pools
being mounted, and `mount-zfs` was tasked with the full responsibility
of importing the needed pool, but nowadays it is wrong behavior and
should be suppressed.

I deduced that self-deletion was the correct thing to do by looking at
other Dracut code, because (as we all are very fully aware of) Dracut
is entirely, ahem, "implementation-defined".

Tested-by: @wphilips 
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Manuel Amador (Rudd-O) <rudd-o@rudd-o.com>
Closes #5157 
Closes #5204
2016-10-06 10:26:47 -07:00
Manuel Amador (Rudd-O) d402c18dd6 A collection of dracut fixes
- In older systems without sysroot.mount, import before dracut-mount,
  and re-enable old dracut mount hook
- rootflags MUST be present even if the administrator neglected to
  specify it explicitly
- Check that mount.zfs exists in sbindir
- Remove awk and head as (now unused) requirements, add grep, and
  install the right mount.zfs
- Eliminate one use of grep in Dracut
- Use a more accurate grepping statement to identify zfsutil in rootflags
- Ensure that pooldev is nonempty
- Properly handle /dev/sd* devices and more
- Use new -P to get list of zpool devices
- Bail out of the generator when zfs:AUTO is on the root command line
- Ignore errors from systemctl trying to load sysroot.mount, we only
  care about the output
- Determine which one is the correct initqueuedir at run time.
- Add a compatibility getargbool for our detection / setup script.
- Update dracut .gitignore files

Signed-off-by: <Matthew Thode mthode@mthode.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4558
Closes #4562
2016-05-12 14:31:15 -07:00
Matthew Thode a5a370227e fix booting via dracut generated initramfs
Dracut and Systemd updated how they integrate with each other, because
of this our current integrations stopped working (around the time
4.1.13 came out).  This patch addresses that issue and gets us booting
again.

Thanks to @Rudd-O for doing the work to get dracut working again and
letting me submit this on his behalf.

Signed-off-by: Manuel Amador (Rudd-O) <rudd-o@rudd-o.com>
Signed-off-by: Matthew Thode <mthode@mthode.org>
Closes #3605
Closes #4478
2016-04-25 08:51:38 -07:00