openstack
/
diskimage-builder
Code Issues Proposed changes

Recreate initramfs within loopback image 

dracut has a loop [1] where it probes top-level directories, tries to
find what block device they are on, then determines the file-system of
that block device.  It then puts those file-system modules into the
initramfs for boot.

Since we install the kernel package during the chroot phase, / there
is not a block device and thus this loop matches nothing and we end up
with no file-system modules in the initramfs.  This results in a very
annoying silent boot hang.

By moving re-generation of dracut into finalise.d phase, we run inside
the final image where / is the loop-device; the root file-system gets
detected correctly and the ext4 module is included correctly.

[1] http://git.kernel.org/cgit/boot/dracut/dracut.git/tree/dracut.sh?h=RHEL-7#n1041

Change-Id: Iaf2a1e8470f642bfaaaad3f9b7f26cfc8cc445c9
Signed-off-by: Paul Belanger <pabelanger@redhat.com>
This commit is contained in:
Ian Wienand 2016-12-15 17:07:04 +11:00 committed by Paul Belanger
parent 280896759a
commit a72645f431
1 changed files with 12 additions and 0 deletions
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12
elements/yum-minimal/finalise.d/55-dracut-recreate Executable file
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#!/bin/bash
# Recreate the initramfs within the loop device so everything gets
# picked up correctly.
if [ ${DIB_DEBUG_TRACE:-1} -gt 0 ]; then
set -x
fi
set -eu
set -o pipefail
dracut --regenerate-all --force --verbose