Kernel panic at early boot time

[mnln.l4]

I get a kernel panic at early boot time on 9.0-stable (r237150), GENERIC,
AMD64.

Repro step:
1. Boot, wait for welcome screen.
2. Repeat pressing Enter key rapidly (so kernel is loading, don't stop
pressing Enter key).
3. See the following message at early boot

*
*
*ACPI APIC Table: <ALASKA A M I>*
*panic: AP #1 (PHY# 2) failed!*

*cpuid = 0*
*KDB: stack backtrace: **(address is remove below in backtrace)*
*#0 kdb_backtrace*
*#1 panic*
*#2 cpu_mp_start*
*#3 mp_start*
*#4 mi_startup*
*#5 btext*
*
*
I can repro about 5 out of 10 times.
*
*
I attached dmesg log captured during normal boot. The box has a MSI
H67MA-E35 motherboard, Intel H67 chipset. The usb keyboard is connected to
a hub then to the machine.

Thanks.
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