Xen fails to boot

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

Hello,
since 2018-07-07 07:00 UTC, Xen DOMUs from HEAD fails to boot (as seen at:
http://www-soc.lip6.fr/~bouyer/NetBSD-tests/xen/HEAD/)
[   1.0000000] Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
[   1.0000000]     2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017,
[   1.0000000]     2018 The NetBSD Foundation, Inc.  All rights reserved.
[   1.0000000] Copyright (c) 1982, 1986, 1989, 1991, 1993
[   1.0000000]     The Regents of the University of California.  All rights reserved.

[   1.0000000] NetBSD 8.99.21 (INSTALL_XEN3PAE_DOMU) #0: Sat Jul 14 00:47:33 UTC 2018
[   1.0000000] 	mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/xen/compile/INSTALL_XEN3PAE_DOMU
[   1.0000000] total memory = 256 MB
[   1.0000000] avail memory = 237 MB
[   1.0000000] running cgd selftest aes-xts-256 aes-xts-512 done
[   1.0000000] mainbus0 (root)
[   1.0000000] hypervisor0 at mainbus0: Xen version 4.11.0nb0
[   1.0000000] vcpu0 at hypervisor0
[   1.0000000] vcpu0: Intel(R) Xeon(TM) CPU 3.00GHz, id 0xf64
[   1.0000000] vcpu0: package 0, core 1, smt 1
[   1.0000000] vcpu1 at hypervisor0
[   1.0000000] vcpu1: Intel(R) Xeon(TM) CPU 3.00GHz, id 0xf64
[   1.0000000] vcpu1: package 1, core 0, smt 0
[   1.0000000] vcpu2 at hypervisor0
[   1.0000000] vcpu2: Intel(R) Xeon(TM) CPU 3.00GHz, id 0xf64
[   1.0000000] vcpu2: package 0, core 0, smt 1
[   1.0000000] vcpu3 at hypervisor0
[   1.0000000] vcpu3: Intel(R) Xeon(TM) CPU 3.00GHz, id 0xf64
[   1.0000000] vcpu3: package 1, core 1, smt 0
[   1.0000000] xenbus0 at hypervisor0: Xen Virtual Bus Interface
[   1.0000000] xencons0 at hypervisor0: Xen Virtual Console Driver
[   1.0000030] fatal protection fault in supervisor mode
[   1.0000030] trap type 4 code 0 eip 0xc053e5b1 cs 0x9 eflags 0x10206 cr2 0 ilevel 0x8 esp 0x206
[   1.0000030] curlwp 0xc0b25e80 pid 0 lid 1 lowest kstack 0xc0d4f2c0
kernel: supervisor trap protection fault, code=0
Stopped in pid 0.1 (system) at  netbsd:__sync_val_compare_and_swap_8+0x1: cli
ds          11
es          11
fs          31
gs          11
edi         c0b1bec0    cpu_info_primary
esi         0
ebp         c0d51ec0
ebx         0
edx         1a59
ecx         0
eax         636bd0e3
eip         c053e5b1    __sync_val_compare_and_swap_8+0x1
cs          9
eflags      10206
esp         c0d51e78
ss          11
netbsd:__sync_val_compare_and_swap_8+0x1:       cli

(cli/sti can't be used from Xen kernels).
It's still the case with 2018-07-14 05:40 UTC kernels.
has this been fixed since then ?

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--