Partial update of bootscripts
bruce.dubbs at gmail.com
Mon Jul 11 08:55:20 PDT 2011
Bryan Kadzban wrote:
> Bruce Dubbs wrote:
>> 5. Updated udev_retry to handle the /run directory for events that
>> occur between starting udevd and mounting / read/write.
> Good, it's using the same thing the rule_generator.functions file is
> using (see choose_rules_file): "udevadm info --run".
> Though it looks a little strange to be searching $PATH for udevadm
> there, yet be specifying /sbin/udevadm through the rest of the script.
> Consistency might be good.
Good point. I added the path.
> It actually probably makes sense to pull this out into its own change?
> We'll need it with newer udev versions no matter what happens to the
> rest (and maybe current udev versions; I'm not sure). Up to you though.
I'm not sure what you mean.
>> Actually this script may need to be reviewed in more detail, because
>> /run is always mounted r/w before udevd is started.
> Hmm, not sure this why this matters? :-)
> /run is mounted read-write, yes -- that's the only reason these rules
> files would have been successfully written there. This whole setup is
> here to catch the case where the rules are generated before the *root*
> FS is mounted read-write (so /etc/udev/rules.d is not writable). And
> AFAIK the root FS can't be mounted read-write before udevadm trigger
> happens, unless I'm missing something. (Because the root FS's device
> node is not present.)
One purpose of the /run directory is to allow (eventually) / to be able
to remain read only. Things like mtab, blkid.tab, etc will migrate to
/run. I'd think dynamic udev rules would move there too. I don't know
why any rules would have to be delayed and that would mean that
udev_retry would be unnecessary.
More information about the lfs-dev