I've looked at the LVM rules used in dracut just recently
and it needs fixing - we should react to change events only
for DM devices, so we have to skip vol_id/blkid call on ADD:
KERNEL=="dm-[0-9]*", ACTION=="add", GOTO="lvm_end"
Also, MD devices have their own rules, where vol_id/blkid
is called and where the symlinks are created (when looking
into raw initrd, this is in 64-md-raid.rules).
Also, if those rules are meant to be for DM devices only,
maybe we should skip symlink creation for the other devices
there, to keep the rules clean and straightforward. I think
we shouldn't create/recreate symlinks for non-dm devices in
LVM/DM rules (..should be in appropriate rules for that type
of device):
KERNEL!="dm-[0-9]*", GOTO="lvm_end"
Having it unconditionally pass pulls in all the networking cruft even
for systems that do not need it, and that sorta defeats the purpose of
hostonly mode.
Supported cmdline formats:
fcoe=<networkdevice>:<dcb|nodcb>
fcoe=<macaddress>:<dcb|nodcb>
Note currently only nodcb is supported, the dcb option is reserved for
future use.
Note letters in the macaddress must be lowercase!
Examples:
fcoe=eth0:nodcb
fcoe=4A:3F:4C:04:F8:D7:nodcb
This introduces filter_kernel_modules, which should be used to install
all kernel modules that match whatever criteria you want.
If running in --hostonly, filter_kernel_modules will only consider
modules that are loaded in the kernel, otherwise it will consider
all the modules installed on the system for the appropriate kernel.
This drastically reduces initramfs generation time when using --hostonly
by eliminating lots of unneeded filesystem activity.
Instead of grovelling through all the modules available for the
kernel looking for block devices, only look at the modules that are
actually loaded. This speeds things up by a rather large amount
when generating the initramfs with --hostonly.
While we are at it, only load the filesystem module that will actually
be used for the root filesystem when running in --hostonly instead
of all the filesystem modules that happen to be loaded at the time.
Since different distros may or may not use vol_id in udev, and blkid
is generally replacing vol_id, abstract them out into a function which
tries to use vol_id first and blkid second, on the assumption that
blkid can take over for vol_id if vol_id is no longer there.
Harald Hoyer