Description of problem:

Hangs right after seabios:

Serial Graphics Adapter 06/19/15
SGABIOS $Id: sgabios.S 8 2010-04-22 00:03:40Z nlaredo $ (mockbuild@) Fri Jun 19 00:52:18 UTC 2015
Term: 80x24
4 0
SeaBIOS (version 1.9.0-1.fc24)
Machine UUID 7a0b0428-2db4-504c-92b7-75c04deb7c74
Booting from ROM...
Probing EDD (edd=off to disable)... ok
\x1b[2J

Version-Release number of selected component (if applicable):

qemu-system-x86-2.5.0-4.fc24.i686
seabios-bin-1.9.0-1.fc24.noarch
kernel-PAE-4.5.0-0.rc1.git0.1.fc24.i686

How reproducible:

100%

Steps to Reproduce:
1. Run libguestfs-test-tool.

Additional info:

The same kernel version boots fine on x86-64.  The problem is specific
to i686.

I also tried:

kernel-PAE-4.5.0-0.rc0.git9.1.fc24.i686  - hangs (same place)
kernel-PAE-4.5.0-0.rc0.git8.1.fc24.i686 - failed to install
kernel-PAE-4.5.0-0.rc0.git7.1.fc24.i686 - failed to install
kernel-PAE-4.5.0-0.rc0.git1.1.fc24.i686 - failed to install

All the install failures were like this:

Error: package kernel-PAE-4.5.0-0.rc0.git1.1.fc24.i686 requires kernel-PAE-core-uname-r = 4.5.0-0.rc0.git1.1.fc24.i686+PAE, but none of the providers can be installed

Perhaps these kernel packages don't have a good "downgrade" path.

Full build logs of failing build in Koji:

https://kojipkgs.fedoraproject.org//work/tasks/2014/12692014/root.log
https://kojipkgs.fedoraproject.org//work/tasks/2014/12692014/build.log