[Xen-devel] Xen 4.12.0-rc Hangs Around masked ExtINT on CPU#

["John L. Poole" <jlpoole56@xxxxxxxxx>]

Boot Hangs at: HVM: HAP page sizes: 4kB, 2MB or Adding cpu [INSERT 1-7] 
to runqueue 0
Log (preserved for 6 months at https://pastebin.com/BDPP7Pzk)

fs0:\efi\gentoo> man_xen.efiip startup.nsh, any other key to continue.
Xen 4.12.0-rc (c/s Mon Feb 25 13:06:22 2019 +0000 git:f393b82fe5-dirty) 
EFI loader
Using configuration file 'man_xen.cfg'
xen-4.12.0-rc.gz: 0x000000005ad2b000-0x000000005ae49640
0x0000:0x02:0x00.0x0: ROM: 0x8000 bytes at 0x7c8bc028
 Xen 4.12.0-rc
(XEN) [00000024693d1c40] Xen version 4.12.0-rc (root@[unknown]) (gcc 
(Gentoo 8.2.0-r6 p1.7) 8.2.0) debug=y  Wed Mar 20 22:35:59 PDT 2019
(XEN) [000000246afc47a8] Latest ChangeSet: Mon Feb 25 13:06:22 2019 
+0000 git:f393b82fe5-dirty
(XEN) [000000246c2cdd38] Console output is synchronous.
(XEN) [000000246ce239e0] Bootloader: EFI
(XEN) [000000246d6f0cc8] Command line: console=vga,com1 com1=115200,8n1 
console_timestamps console_to_ring conring_size=64 log_buf_len=16M 
loglvl=all guest_loglvl=all sync_console=true sched_debug iommu=verbose 
apic_verbosity=debug efi=no-rs reboot=kbd
(XEN) [00000024709d96d0] Xen image load base address: 0x5b000000
(XEN) [00000024716f7420] Video information:
(XEN) [000000247205f6d0]  VGA is graphics mode 800x600, 32 bpp
(XEN) [0000002472d0f8d8] Disc information:
(XEN) [00000024735d5510]  Found 0 MBR signatures
(XEN) [0000002474042280]  Found 1 EDD information structures
(XEN) [0000002474c89b48] EFI RAM map:
(XEN) [0000002475448878]  0000000000000000 - 00000000000a0000 (usable)
(XEN) [0000002476427298]  0000000000100000 - 000000007e16b000 (usable)
(XEN) [0000002477273790]  000000007e16b000 - 000000007eba2000 (reserved)
(XEN) [000000247811aa98]  000000007eba2000 - 000000007ed0d000 (usable)
(XEN) [0000002478fd4af0]  000000007ed0d000 - 000000007f28d000 (ACPI NVS)
(XEN) [0000002479e80a18]  000000007f28d000 - 000000007f648000 (reserved)
(XEN) [000000247adbe038]  000000007f648000 - 000000007f800000 (usable)
(XEN) [000000247bc044b8]  00000000e0000000 - 00000000e4000000 (reserved)
(XEN) [000000247cab3db8]  00000000fed01000 - 00000000fed04000 (reserved)
(XEN) [000000247d9ebeb8]  00000000fed08000 - 00000000fed09000 (reserved)
(XEN) [000000247e893070]  00000000fed0c000 - 00000000fed10000 (reserved)
(XEN) [000000247f7c1f60]  00000000fed1c000 - 00000000fed1d000 (reserved)
(XEN) [000000248066f790]  00000000fef00000 - 00000000ff000000 (reserved)
(XEN) [000000248151b790]  00000000ff800000 - 0000000100000000 (reserved)
(XEN) [0000002482453308]  0000000100000000 - 0000000ff0000000 (usable)
(XEN) [000000248366b500] ACPI: RSDP 7ED55000, 0024 (r2 ALASKA)
(XEN) [00000024843b69e8] ACPI: XSDT 7ED55098, 00B4 (r1 ALASKA   A M I   
1072009 AMI     10013)
(XEN) [00000024856c0830] ACPI: FACP 7ED58690, 010C (r5 ALASKA   A M I   
1072009 AMI     10013)
(XEN) [0000002486a2b500] ACPI: DSDT 7ED551E8, 34A1 (r2 ALASKA   A M I   
1072009 INTL 20061109)
(XEN) [0000002487db8898] ACPI: FACS 7F28AF80, 0040
(XEN) [0000002488871280] ACPI: FPDT 7ED587A0, 0044 (r1 ALASKA   A M I   
1072009 AMI     10013)
(XEN) [0000002489b7b248] ACPI: FIDT 7ED587E8, 009C (r1 ALASKA   A M I   
1072009 AMI     10013)
(XEN) [000000248af0ab18] ACPI: SPMI 7ED58888, 0040 (r5 ALASKA   A M 
I         0 AMI.        0)
(XEN) [000000248c214dc8] ACPI: MCFG 7ED588C8, 003C (r1 ALASKA    A M I  
1072009 MSFT       97)
(XEN) [000000248d5a7ce0] ACPI: WDAT 7ED58908, 01AC (r1 ALASKA    A M I  
1072009 MSFT    10013)
(XEN) [000000248e8b0190] ACPI: UEFI 7ED58AB8, 0042 
(r1                        0             0)
(XEN) [000000248fc428e0] ACPI: APIC 7ED58B00, 0098 (r3 INTEL 
TIANO           1 MSFT        0)
(XEN) [0000002490f49dd0] ACPI: BDAT 7ED58B98, 0030 
(r1                        0             0)
(XEN) [00000024922e04e0] ACPI: HPET 7ED58BC8, 0038 (r1 
INTEL                  1 MSFT  1000013)
(XEN) [00000024935e57b0] ACPI: SSDT 7ED58C00, 09F1 (r1  PmRef CpuPm     
3000 INTL 20061109)
(XEN) [0000002494a8cdd0] ACPI: SSDT 7ED595F8, 0259 (r1  PmRef 
Cpu0Tst     3000 INTL 20061109)
(XEN) [0000002495d95070] ACPI: SSDT 7ED59858, 0357 (r1  PmRef ApTst     
3000 INTL 20061109)
(XEN) [000000249711b280] ACPI: SPCR 7ED59BB0, 0050 (r1  A M I APTIO V  
1072009 AMI.        5)
(XEN) [000000249841f650] ACPI: HEST 7ED59C00, 00A8 (r1 INTEL AVOTON 
B        1 INTL        1)
(XEN) [00000024997b69a8] ACPI: BERT 7ED59CA8, 0030 (r1 INTEL AVOTON 
B        1 INTL        1)
(XEN) [000000249aabafd0] ACPI: ERST 7ED59CD8, 0230 (r1 INTEL AVOTON 
B        1 INTL        1)
(XEN) [000000249be4f688] ACPI: EINJ 7ED59F08, 0150 (r1 INTEL AVOTON 
B        1 INTL        1)
(XEN) [000000249da28708] System RAM: 63204MB (64721080kB)
(XEN) [00000024b155f680] No NUMA configuration found
(XEN) [00000024b21f32e0] Faking a node at 0000000000000000-0000000ff0000000
(XEN) [00000027a6d2aa00] Domain heap initialised
(XEN) [00000027a77e1e40] Allocated console ring of 64 KiB.
(XEN) [00000027dde7d060] vesafb: framebuffer at 0xde000000, mapped to 
0xffff82c000201000, using 1920k, total 1920k
(XEN) [00000027df602ed0] vesafb: mode is 800x600x32, linelength=3200, 
font 8x8
(XEN) [00000027e05e2670] vesafb: Truecolor: size=8:8:8:8, shift=24:16:8:0
(XEN) [00000027e1560f58] CPU Vendor: Intel, Family 6 (0x6), Model 77 
(0x4d), Stepping 8 (raw 000406d8)
(XEN) [00000027f9e790d8] SMBIOS 2.8 present.
(XEN) [00000027fa894e90] DMI 2.7 present.
(XEN) [00000027fb23d3a0] APIC boot state is 'xapic'
(XEN) [00000027fbdfa3b0] Using APIC driver default
(XEN) [00000027fca7c5e0] ACPI: PM-Timer IO Port: 0x408 (32 bits)
(XEN) [00000027fd92f510] ACPI: v5 SLEEP INFO: control[0:0], status[0:0]
(XEN) [00000027fe9f4720] ACPI: SLEEP INFO: pm1x_cnt[1:404,1:0], 
pm1x_evt[1:400,1:0]
(XEN) [00000027ffd14f90] ACPI: 32/64X FACS address mismatch in FADT - 
7f28af80/0000000000000000, using 32
(XEN) [00000028014468c0] ACPI:             wakeup_vec[7f28af8c], 
vec_size[20]
(XEN) [0000002802603888] ACPI: Local APIC address 0xfee00000
(XEN) [0000002803474140] ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled)
(XEN) [00000028045a86c8] ACPI: LAPIC (acpi_id[0x02] lapic_id[0x02] enabled)
(XEN) [000000280576d568] ACPI: LAPIC (acpi_id[0x03] lapic_id[0x04] enabled)
(XEN) [00000028068a4d18] ACPI: LAPIC (acpi_id[0x04] lapic_id[0x06] enabled)
(XEN) [0000002807a64b90] ACPI: LAPIC (acpi_id[0x05] lapic_id[0x08] enabled)
(XEN) [0000002808bab340] ACPI: LAPIC (acpi_id[0x06] lapic_id[0x0a] enabled)
(XEN) [0000002809ddc660] ACPI: LAPIC (acpi_id[0x07] lapic_id[0x0c] enabled)
(XEN) [000000280af14098] ACPI: LAPIC (acpi_id[0x08] lapic_id[0x0e] enabled)
(XEN) [000000280c16f028] ACPI: LAPIC_NMI (acpi_id[0x01] high edge lint[0x1])
(XEN) [000000280d2eccf0] ACPI: LAPIC_NMI (acpi_id[0x02] high edge lint[0x1])
(XEN) [000000280e685f98] ACPI: IOAPIC (id[0x02] address[0xfec00000] 
gsi_base[0])
(XEN) [000000280f8e7c48] IOAPIC[0]: apic_id 2, version 32, address 
0xfec00000, GSI 0-23
(XEN) [0000002810d8df48] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 
dfl dfl)
(XEN) [000000281202a4b8] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 
high level)
(XEN) [0000002813501280] ACPI: IRQ0 used by override.
(XEN) [000000281413eab0] ACPI: IRQ2 used by override.
(XEN) [0000002814d7c6a0] ACPI: IRQ9 used by override.
(XEN) [0000002815a8a748] Enabling APIC mode:  Flat.  Using 1 I/O APICs
(XEN) [0000002816aaf428] ACPI: HPET id: 0x8086a201 base: 0xfed00000
(XEN) [0000002817a95510] PCI: MCFG configuration 0: base e0000000 
segment 0000 buses 00 - ff
(XEN) [0000002818fc7eb0] PCI: MCFG area at e0000000 reserved in E820
(XEN) [0000002819fe6848] PCI: updated MCFG configuration 0: base 
e0000000 segment 0 buses 0 - 63
(XEN) [000000281b6072f8] PCI: Using MCFG for segment 0000 bus 00-3f
(XEN) [000000281c62ea80] Xen ERST support is initialized.
(XEN) [000000281d364ad0] HEST: Table parsing has been initialized
(XEN) [000000281e25e9c8] Using ACPI (MADT) for SMP configuration information
(XEN) [000000281f45cca0] SMP: Allowing 8 CPUs (0 hotplug CPUs)
(XEN) [00000028202c5590] mapped APIC to ffff82cfffffb000 (fee00000)
(XEN) [000000282129d038] mapped IOAPIC to ffff82cfffffa000 (fec00000)
(XEN) [0000002822279b38] IRQ limits: 24 GSI, 1528 MSI/MSI-X
(XEN) [0000002823142ec0] mce_intel.c:780: MCA Capability: firstbank 0, 
extended MCE MSR 0, BCAST
(XEN) [0000002824749450] CPU0: Intel machine check reporting enabled
(XEN) [00000028257a81f8] Unrecognised CPU model 0x4d - assuming not 
reptpoline safe
(XEN) [0000002826ac5fa8] Speculative mitigation facilities:
(XEN) [0000002827944db0]   Hardware features:
(XEN) [0000002828399640]   Compiled-in support: INDIRECT_THUNK SHADOW_PAGING
(XEN) [0000002829518be0]   Xen settings: BTI-Thunk RETPOLINE, SPEC_CTRL: 
No, Other:
(XEN) [000000282a8c0528]   Support for HVM VMs: RSB
(XEN) [000000282b560278]   Support for PV VMs: RSB
(XEN) [000000282c1cdb08]   XPTI (64-bit PV only): Dom0 enabled, DomU 
enabled (without PCID)
(XEN) [000000282d6bfc48]   PV L1TF shadowing: Dom0 disabled, DomU disabled
(XEN) [000000282e866c38] Using scheduler: SMP Credit Scheduler rev2 
(credit2)
(XEN) [000000282fa0da00] Initializing Credit2 scheduler
(XEN) [00000028306bd4d0]  load_precision_shift: 18
(XEN) [00000028312c5ed0]  load_window_shift: 30
(XEN) [0000002831e42758]  underload_balance_tolerance: 0
(XEN) [0000002832b28468]  overload_balance_tolerance: -3
(XEN) [0000002833886058]  runqueues arrangement: socket
(XEN) [0000002834533890]  cap enforcement granularity: 10ms
(XEN) [00000028353bb4a0] load tracking window length 1073741824 ns
(XEN) [00000028362f7500] Adding cpu 0 to runqueue 0
(XEN) [0000002836ec43e0]  First cpu on runqueue, activating
(XEN) [000000283ef8c6b8] Platform timer is 14.318MHz HPET
(XEN) [   72.057296] Detected 2399.047 MHz processor.
(XEN) [   72.071612] EFI memory map:
(XEN) [   72.074956]  0000000000000-0000000007fff type=3 
attr=000000000000000f
(XEN) [   72.082744]  0000000008000-000000003dfff type=7 
attr=000000000000000f
(XEN) [   72.090269]  000000003e000-000000003ffff type=2 
attr=000000000000000f
(XEN) [   72.097941]  0000000040000-000000009ffff type=3 
attr=000000000000000f
(XEN) [   72.105466]  0000000100000-00000001fffff type=7 
attr=000000000000000f
(XEN) [   72.113175]  0000000200000-000000023ffff type=4 
attr=000000000000000f
(XEN) [   72.120917]  0000000240000-000005ad2afff type=7 
attr=000000000000000f
(XEN) [   72.163315]  000005ad2b000-000005ae53fff type=2 
attr=000000000000000f
(XEN) [   72.205563]  000005ae54000-000005c110fff type=1 
attr=000000000000000f
(XEN) [   72.248048]  000005c111000-000007ad5afff type=2 
attr=000000000000000f
(XEN) [   72.290932]  000007ad5b000-000007ad5efff type=7 
attr=000000000000000f
(XEN) [   72.333997]  000007ad5f000-000007ad64fff type=2 
attr=000000000000000f
(XEN) [   72.377007]  000007ad65000-000007ad65fff type=7 
attr=000000000000000f
(XEN) [   72.420576]  000007ad66000-000007ad66fff type=2 
attr=000000000000000f
(XEN) [   72.463962]  000007ad67000-000007ad67fff type=7 
attr=000000000000000f
(XEN) [   72.506928]  000007ad68000-000007ad6afff type=2 
attr=000000000000000f
(XEN) [   72.550292]  000007ad6b000-000007ad73fff type=7 
attr=000000000000000f
(XEN) [   72.593815]  000007ad74000-000007ad7efff type=2 
attr=000000000000000f
(XEN) [   72.636525]  000007ad7f000-000007db6afff type=4 
attr=000000000000000f
(XEN) [   72.679425]  000007db6b000-000007df0ffff type=7 
attr=000000000000000f
(XEN) [   72.722532]  000007df10000-000007e16afff type=3 
attr=000000000000000f
(XEN) [   72.765658]  000007e16b000-000007eba1fff type=0 
attr=000000000000000f
(XEN) [   72.809009]  000007eba2000-000007ed0cfff type=7 
attr=000000000000000f
(XEN) [   72.852010]  000007ed0d000-000007f28cfff type=10 
attr=000000000000000f
(XEN) [   72.895302]  000007f28d000-000007f5f2fff type=6 
attr=800000000000000f
(XEN) [   72.937987]  000007f5f3000-000007f647fff type=5 
attr=800000000000000f
(XEN) [   72.981389]  000007f648000-000007f7fffff type=4 
attr=000000000000000f
(XEN) [   73.025007]  0000100000000-0000fefffffff type=7 
attr=000000000000000f
(XEN) [   73.067909]  00000e0000000-00000e3ffffff type=11 
attr=8000000000000001
(XEN) [   73.111120]  00000fed01000-00000fed03fff type=11 
attr=8000000000000001
(XEN) [   73.154487]  00000fed08000-00000fed08fff type=11 
attr=8000000000000001
(XEN) [   73.197629]  00000fed0c000-00000fed0ffff type=11 
attr=8000000000000001
(XEN) [   73.241260]  00000fed1c000-00000fed1cfff type=11 
attr=8000000000000001
(XEN) [   73.284256]  00000fef00000-00000feffffff type=11 
attr=8000000000000001
(XEN) [   73.327462]  00000ff800000-00000ffffffff type=11 
attr=8000000000000001
(XEN) [   73.370746] Initing memory sharing.
(XEN) [   73.410811] alt table ffff82d080674c70 -> ffff82d080676a68
(XEN) [   73.454321] I/O virtualisation disabled
(XEN) [   73.495438] nr_sockets: 1
(XEN) [   73.534743] Getting VERSION: 50014
(XEN) [   73.575240] Getting VERSION: 50014
(XEN) [   73.614700] Getting ID: 0
(XEN) [   73.653432] Getting LVT0: 700
(XEN) [   73.692536] Getting LVT1: 400
(XEN) [   73.731789] enabled ExtINT on CPU#0
(XEN) [   73.770190] ENABLING IO-APIC IRQs
(XEN) [   73.808477]  -> Using new ACK method
(XEN) [   73.846109] init IO_APIC IRQs
(XEN) [   73.883940]  IO-APIC (apicid-pin) 2-0, 2-16, 2-17, 2-18, 2-19, 
2-20, 2-21, 2-22, 2-23 not connected.
(XEN) [   73.965229] ..TIMER: vector=0xF0 apic1=0 pin1=2 apic2=-1 pin2=-1
(XEN) [   74.106548] number of MP IRQ sources: 15.
(XEN) [   74.145195] number of IO-APIC #2 registers: 24.
(XEN) [   74.184159] testing the IO APIC.......................
(XEN) [   74.224688] IO APIC #2......
(XEN) [   74.262138] .... register #00: 02000000
(XEN) [   74.299887] .......    : physical APIC id: 02
(XEN) [   74.337690] .......    : Delivery Type: 0
(XEN) [   74.375168] .......    : LTS          : 0
(XEN) [   74.413463] .... register #01: 00170020
(XEN) [   74.451529] .......     : max redirection entries: 0017
(XEN) [   74.489582] .......     : PRQ implemented: 0
(XEN) [   74.526914] .......     : IO APIC version: 0020
(XEN) [   74.564517] .... IRQ redirection table:
(XEN) [   74.602092]  NR Log Phy Mask Trig IRR Pol Stat Dest Deli Vect:
(XEN) [   74.641885]  00 000 00  1    0    0   0   0    0    0 00
(XEN) [   74.681877]  01 001 01  0    0    0   0   0    1    1 28
(XEN) [   74.722577]  02 001 01  0    0    0   0   0    1    1 F0
(XEN) [   74.762500]  03 001 01  0    0    0   0   0    1    1 30
(XEN) [   74.802607]  04 001 01  1    0    0   0   0    1    1 F1
(XEN) [   74.843045]  05 001 01  0    0    0   0   0    1    1 38
(XEN) [   74.883117]  06 001 01  0    0    0   0   0    1    1 40
(XEN) [   74.923458]  07 001 01  0    0    0   0   0    1    1 48
(XEN) [   74.963574]  08 001 01  0    0    0   0   0    1    1 50
(XEN) [   75.003555]  09 001 01  1    1    0   0   0    1    1 58
(XEN) [   75.044071]  0a 001 01  0    0    0   0   0    1    1 60
(XEN) [   75.083822]  0b 001 01  0    0    0   0   0    1    1 68
(XEN) [   75.123683]  0c 001 01  0    0    0   0   0    1    1 70
(XEN) [   75.163876]  0d 001 01  0    0    0   0   0    1    1 78
(XEN) [   75.203588]  0e 001 01  0    0    0   0   0    1    1 88
(XEN) [   75.243635]  0f 001 01  0    0    0   0   0    1    1 90
(XEN) [   75.283365]  10 08D 0D  1    0    0   0   0    0    2 F7
(XEN) [   75.322818]  11 000 00  1    0    0   0   0    0    0 00
(XEN) [   75.362882]  12 000 00  1    0    0   0   0    0    0 00
(XEN) [   75.402330]  13 000 00  1    0    0   0   0    0    0 00
(XEN) [   75.442553]  14 000 00  1    0    0   0   0    0    0 00
(XEN) [   75.481903]  15 000 00  1    0    0   0   0    0    0 00
(XEN) [   75.521633]  16 000 00  1    0    0   0   0    0    0 00
(XEN) [   75.561389]  17 000 00  1    0    0   0   0    0    0 00
(XEN) [   75.601074] Using vector-based indexing
(XEN) [   75.637043] IRQ to pin mappings:
(XEN) [   75.673259] IRQ240 -> 0:2
(XEN) [   75.709316] IRQ40 -> 0:1
(XEN) [   75.743641] IRQ48 -> 0:3
(XEN) [   75.779468] IRQ241 -> 0:4
(XEN) [   75.813390] IRQ56 -> 0:5
(XEN) [   75.848219] IRQ64 -> 0:6
(XEN) [   75.882180] IRQ72 -> 0:7
(XEN) [   75.916590] IRQ80 -> 0:8
(XEN) [   75.949802] IRQ88 -> 0:9
(XEN) [   75.985189] IRQ96 -> 0:10
(XEN) [   76.018278] IRQ104 -> 0:11
(XEN) [   76.050553] IRQ112 -> 0:12
(XEN) [   76.085008] IRQ120 -> 0:13
(XEN) [   76.117439] IRQ136 -> 0:14
(XEN) [   76.149053] IRQ144 -> 0:15
(XEN) [   76.180044] .................................... done.
(XEN) [   76.213471] Using local APIC timer interrupts.
(XEN) [   76.247000] calibrating APIC timer ...
(XEN) [   76.383322] ..... CPU clock speed is 2400.0482 MHz.
(XEN) [   76.415850] ..... host bus clock speed is 100.0019 MHz.
(XEN) [   76.448293] ..... bus_scale = 0x6669
(XEN) [   76.478840] TSC deadline timer enabled
(XEN) [2019-03-21 16:15:08] mwait-idle: MWAIT substates: 0x3000020
(XEN) [2019-03-21 16:15:08] mwait-idle: v0.4.1 model 0x4d
(XEN) [2019-03-21 16:15:08] mwait-idle: lapic_timer_reliable_states 
0xffffffff
(XEN) [2019-03-21 16:15:08] VMX: Supported advanced features:
(XEN) [2019-03-21 16:15:08]  - APIC MMIO access virtualisation
(XEN) [2019-03-21 16:15:08]  - APIC TPR shadow
(XEN) [2019-03-21 16:15:08]  - Extended Page Tables (EPT)
(XEN) [2019-03-21 16:15:08]  - Virtual-Processor Identifiers (VPID)
(XEN) [2019-03-21 16:15:08]  - Virtual NMI
(XEN) [2019-03-21 16:15:08]  - MSR direct-access bitmap
(XEN) [2019-03-21 16:15:08]  - Unrestricted Guest
(XEN) [2019-03-21 16:15:08]  - VM Functions
(XEN) [2019-03-21 16:15:09] HVM: ASIDs enabled.
(XEN) [2019-03-21 16:15:09] HVM: VMX enabled
(XEN) [2019-03-21 16:15:09] HVM: Hardware Assisted Paging (HAP) detected
(XEN) [2019-03-21 16:15:09] HVM: HAP page sizes: 4kB, 2MB

I previously contacted XEN-DEV on March 15th at

https://lists.xenproject.org/archives/html/xen-devel/2019-03/msg01281.html

The environment then was a Gentoo-based distribution with patches.  Andrew
Cooper concluded "root of your problem is that Xen can't find the ACPI 
tables,
which is either going to be a grub or a Xen build misconfiguration."

I learned the Gentoo build contained patches maintained by a Gentoo 
developer,
so I decided to try an apples-to-apples approach: I cloned the Xen 
repository
set my python environment to 2.7 and
".configure", "make","make test", & "make install"
and used the EFI loader and kernel created from the Xen source code w/o 
patches,
log of which is above.  My previous Gentoo-based log had:

(XEN) ACPI Error (tbxfroot-0217): A valid RSDP was not found [20070126]

The Xen source build above does not have that error.

Yet, I'm still getting hung sessions either right after the report out of
"HVM: HAP page sizes: 4kB, 2MB" or during the masking such as:

(XEN) [2019-03-21 16:11:43] masked ExtINT on CPU#2
(XEN) [2019-03-21 16:13:40] Adding cpu 2 to runqueue 0

at https://pastebin.com/3EkQdRYA

and

(XEN) [2019-03-21 16:08:54] masked ExtINT on CPU#5
(XEN) [2019-03-21 16:10:05] Adding cpu 5 to runqueue 0

at https://pastebin.com/gUqCVa66

I am not seeing any error messages such the ACPI error message encountered
within the Gentoo-built Xen kernel, yet I am still facing the problem of 
inconsistent
hangs.  Note: unlike with the Gentoo built Kernel, I have not been able to
successfully get past the "masked ExtINT" phase.

Is there something more I can include in the options or provide to help 
identify
what is causing this problem.  The only negative thing I can discern is 
the post of:
(XEN) [00000028257a81f8] Unrecognised CPU model 0x4d - assuming not 
reptpoline safe
And, of course, the Gentoo kernel for a regular Linux session continues 
to boot reliably.
See https://pastebin.com/VDMP0xGD

-- John


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel