Wheezy kernel does not boot on HP zx6000

[Martin Lucina <martin@lucina.net>]

Hi,

today I upgraded a HP zx6000 from squeeze to wheezy and ran into a major
showstopper. The kernel installed by linux-image-mckinley
(linux-image-3.2.0-4-mckinley 3.2.46-1+deb7u1) will not boot on my machine.

The machine has two of the following CPUs in it:

family     : 31
model      : 1
model name : Madison
revision   : 5
archrev    : 0
features   : branchlong
cpu number : 0
cpu regs   : 4
cpu MHz    : 1400.000
itc MHz    : 1400.000000

By "will not boot" I mean that:

1) immediately after ELILO loads the kernel and initrd I see no messages
and the system appears to freeze.

2) after about 60 seconds the diagnostic LEDs on the front panel change to
System - blinking, RED and LED 2 - on, RED and the system reboots.

According to the manual this is a "System firmware hang or system fault".

The system still boots up OK with the squeeze kernel (2.6.32-48squeeze3).

Presumably I should report this as a serious / grave bug against the
linux-image packages, but before I do that I'd like to get some advice on
how I can try and diagnose this, if at all?

Is there any way to bring up some kind of "early console" in the kernel to
try and get a handle on what might be going wrong? Can this be done using a
serial console?

Thanks,

Martin