xen-unstable: xen hang on boot

[Jeremy Fitzhardinge <jeremy@goop.org>]

I just updated Xen from xen-unstable, and its hanging in the middle of
boot, during what appears to be APIC setup:

[...]
(XEN) ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1])
(XEN) ACPI: IOAPIC (id[0x07] address[0xfec00000] gsi_base[0])
(XEN) IOAPIC[0]: apic_id 7, version 32, address 0xfec00000, GSI 0-23
(XEN) ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)
(XEN) ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
(XEN) ACPI: IRQ0 used by override.
(XEN) ACPI: IRQ2 used by override.
(XEN) ACPI: IRQ9 used by override.
(XEN) Enabling APIC mode:  Flat.  Using 1 I/O APICs
(XEN) ACPI: HPET id: 0x8086a701 base: 0xfed00000
[hang]


Full dump below.

The machine is my standard test/dev server, which I've been using for
the last 18 months or so.  The only environmental change is that I've
updated it to F15, which has a new compiler.  But I've compiled Xen with
that on other machines without problems.  I'm not sure what the previous
version of Xen I was using, but xen-unstable from at least a month or
two ago.

Any clues?

Thanks,
    J

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 /_/\_\___|_| |_|    |_|(_)_____|   \__,_|_| |_|___/\__\__,_|_.__/|_|\___|
                                                                          
(XEN) Xen version 4.2-unstable (jeremy@) (gcc version 4.6.0 20110603 (Red Hat 4.6.0-10) (GCC) ) Mon Aug  8 14:51:13 PDT 2011
(XEN) Latest ChangeSet: Thu Jul 28 15:40:54 2011 +0100 23757:0f36c2eec2e1
(XEN) Bootloader: GNU GRUB 0.97
(XEN) Command line: com2=115200,8n1,0x3e8,5 console=com2,vga cpufreq=xen
(XEN) Video information:
(XEN)  VGA is text mode 80x25, font 8x16
(XEN)  VBE/DDC methods: none; EDID transfer time: 0 seconds
(XEN)  EDID info not retrieved because no DDC retrieval method detected
(XEN) Disc information:
(XEN)  Found 5 MBR signatures
(XEN)  Found 5 EDD information structures
(XEN) Xen-e820 RAM map:
(XEN)  0000000000000000 - 000000000009d800 (usable)
(XEN)  000000000009d800 - 00000000000a0000 (reserved)
(XEN)  00000000000e0000 - 0000000000100000 (reserved)
(XEN)  0000000000100000 - 00000000bf790000 (usable)
(XEN)  00000000bf79e000 - 00000000bf7a0000 type 9
(XEN)  00000000bf7a0000 - 00000000bf7ae000 (ACPI data)
(XEN)  00000000bf7ae000 - 00000000bf7d0000 (ACPI NVS)
(XEN)  00000000bf7d0000 - 00000000bf7e0000 (reserved)
(XEN)  00000000bf7ed000 - 00000000c0000000 (reserved)
(XEN)  00000000e0000000 - 00000000f0000000 (reserved)
(XEN)  00000000fed20000 - 00000000fed40000 (reserved)
(XEN)  00000000fee00000 - 00000000fee01000 (reserved)
(XEN)  0000000100000000 - 0000000340000000 (usable)
(XEN) ACPI: RSDP 000FA280, 0024 (r2 ACPIAM)
(XEN) ACPI: XSDT BF7A0100, 0084 (r1 SMCI            20100527 MSFT       97)
(XEN) ACPI: FACP BF7A0290, 00F4 (r3 052710 FACP1450 20100527 MSFT       97)
(XEN) ACPI: DSDT BF7A05F0, 6C7B (r1  10605 10605000        0 INTL 20051117)
(XEN) ACPI: FACS BF7AE000, 0040
(XEN) ACPI: APIC BF7A0390, 0092 (r1 052710 APIC1450 20100527 MSFT       97)
(XEN) ACPI: MCFG BF7A0430, 003C (r1 052710 OEMMCFG  20100527 MSFT       97)
(XEN) ACPI: OEMB BF7AE040, 0073 (r1 052710 OEMB1450 20100527 MSFT       97)
(XEN) ACPI: HPET BF7AA5F0, 0038 (r1 052710 OEMHPET  20100527 MSFT       97)
(XEN) ACPI: GSCI BF7AE0C0, 2024 (r1 052710 GMCHSCI  20100527 MSFT       97)
(XEN) ACPI: DMAR BF7B00F0, 0090 (r1    AMI  OEMDMAR        1 MSFT       97)
(XEN) ACPI: SSDT BF7B1580, 0363 (r1 DpgPmm    CpuPm       12 INTL 20051117)
(XEN) ACPI: EINJ BF7AA630, 0130 (r1  AMIER AMI_EINJ 20100527 MSFT       97)
(XEN) ACPI: BERT BF7AA7C0, 0030 (r1  AMIER AMI_BERT 20100527 MSFT       97)
(XEN) ACPI: ERST BF7AA7F0, 01B0 (r1  AMIER AMI_ERST 20100527 MSFT       97)
(XEN) ACPI: HEST BF7AA9A0, 00A8 (r1  AMIER ABC_HEST 20100527 MSFT       97)
(XEN) System RAM: 12279MB (12573876kB)
(XEN) No NUMA configuration found
(XEN) Faking a node at 0000000000000000-0000000340000000
(XEN) Domain heap initialised
(XEN) found SMP MP-table at 000ff780
(XEN) DMI present.
(XEN) Using APIC driver default
(XEN) ACPI: PM-Timer IO Port: 0x808
(XEN) ACPI: ACPI SLEEP INFO: pm1x_cnt[804,0], pm1x_evt[800,0]
(XEN) ACPI:                  wakeup_vec[bf7ae00c], vec_size[20]
(XEN) ACPI: Local APIC address 0xfee00000
(XEN) ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled)
(XEN) Processor #0 7:14 APIC version 21
(XEN) ACPI: LAPIC (acpi_id[0x02] lapic_id[0x02] enabled)
(XEN) Processor #2 7:14 APIC version 21
(XEN) ACPI: LAPIC (acpi_id[0x03] lapic_id[0x04] enabled)
(XEN) Processor #4 7:14 APIC version 21
(XEN) ACPI: LAPIC (acpi_id[0x04] lapic_id[0x06] enabled)
(XEN) Processor #6 7:14 APIC version 21
(XEN) ACPI: LAPIC (acpi_id[0x05] lapic_id[0x84] disabled)
(XEN) ACPI: LAPIC (acpi_id[0x06] lapic_id[0x85] disabled)
(XEN) ACPI: LAPIC (acpi_id[0x07] lapic_id[0x86] disabled)
(XEN) ACPI: LAPIC (acpi_id[0x08] lapic_id[0x87] disabled)
(XEN) ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1])
(XEN) ACPI: IOAPIC (id[0x07] address[0xfec00000] gsi_base[0])
(XEN) IOAPIC[0]: apic_id 7, version 32, address 0xfec00000, GSI 0-23
(XEN) ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)
(XEN) ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
(XEN) ACPI: IRQ0 used by override.
(XEN) ACPI: IRQ2 used by override.
(XEN) ACPI: IRQ9 used by override.
(XEN) Enabling APIC mode:  Flat.  Using 1 I/O APICs
(XEN) ACPI: HPET id: 0x8086a701 base: 0xfed00000