kern/53980: INSTALL_XEN3PAE_DOMU from -current panics

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         53980
>Category:       kern
>Synopsis:       INSTALL_XEN3PAE_DOMU from -current panics
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Feb 14 15:50:00 +0000 2019
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current, source date 2019.02.14.08.18.26
>Organization:
>Environment:
System: NetBSD
Architecture: i386
Machine: i386
>Description:

Attempting to install a -current i386 domU under xen411 as part of a
suite of automated tests of NetBSD/Xen, the INSTALL_XEN3PAE_DOMU
kernel paniced:

[   1.0000000] NetBSD 8.99.34 (INSTALL_XEN3PAE_DOMU) #0: Thu Feb 14 13:18:51 EET 2019
[   1.0000000]  root%guido.araneus.fi@localhost:/tmp/bracket/build/2019.02.14.08.18.26-i386/obj/sys/arch/i386/compile/INSTALL_XEN3PAE_DOMU
[   1.0000000] total memory = 32768 KB
[   1.0000000] avail memory = 18856 KB
[   1.0000000] running cgd selftest aes-xts-256 aes-xts-512 done
[   1.0000000] mainbus0 (root)
[   1.0000000] hypervisor0 at mainbus0: Xen version 4.11.0nb1
[   1.0000000] vcpu0 at hypervisor0
[   1.0000000] vcpu0: Intel(R) Xeon(R) CPU           L5630  @ 2.13GHz, id 0x206c2
[   1.0000000] vcpu0: package 1, core 0, smt 0
[   1.0000000] xenbus0 at hypervisor0: Xen Virtual Bus Interface
[   1.0000000] xencons0 at hypervisor0: Xen Virtual Console Driver
[   1.0000030] xenbus: can't get state for device/suspend/event-channel (2)
[   1.0000030] xbd0 at xenbus0 id 51712: Xen Virtual Block Device Interface
[   1.0100745] xbd1 at xenbus0 id 51728: Xen Virtual Block Device Interface
[   1.0200695] balloon0 at xenbus0 id 0: Xen Balloon driver
[   1.0200695] balloon0: current reservation: 32768 KiB
[   1.0200695] panic: kernel diagnostic assertion "bp != NULL" failed: file "/tmp/bracket/build/2019.02.14.08.18.26-i386/src/sys/arch/xen/xen/xbd_xenbus.c", line 706 
[   1.0200695] cpu0: Begin traceback...
[   1.0200695] vpanic(c0554a6c,c347ce28,c347ce64,c01393d1,c0554a6c,c0554a06,c0599d1a,c055aac4,2c2,1) at netbsd:vpanic+0x13f
[   1.0200695] kern_assert(c0554a6c,c0554a06,c0599d1a,c055aac4,2c2,1,0,c0ee2160,0,c3507000) at netbsd:kern_assert+0x23
[   1.0200695] xbd_handler(c0ee2008,c0d0e000,6,c0e5b2a8,c347cebc,c011a89f,c0e5b2a8,c347cf14,c0b19bc0,f9b46430) at netbsd:xbd_handler+0x3c1
[   1.0200695] xen_intr_biglock_wrapper(c0e5b2a8,c347cf14,c0b19bc0,f9b46430,cc,f9b8a970,0,80000000,0,c0c259b8) at netbsd:xen_intr_biglock_wrapper+0x1f
[   1.0200695] evtchn_do_event(6,c347cf14,c347cf58,1,c347cef0,0,c0b0b0c0,c0d0e000,c0d0e000,c0d0e800) at netbsd:evtchn_do_event+0x10f
[   1.0200695] do_hypervisor_callback(c347cf14,0,c0110011,c0b00031,c0e60011,c3470011,c0b0b0c0,c0e3ad40,c347cf74,deadf00d) at netbsd:do_hypervisor_callback+0x15c
[   1.0200695] Xhypervisor_pvhvm_callback(c0e3cd20,0,c0e3cd20,c0e3cd20,c0102102,c0e3cd20,c03ad7c0,c0e3cd20,0,c0102031) at netbsd:Xhypervisor_pvhvm_callback+0x67
[   1.0200695] idle_loop(c0e3cd20,d0e000,c0b22200,0,c010007a,0,0,0,0,0) at netbsd:idle_loop+0xbf
[   1.0200695] cpu0: End traceback...
[   1.0200695] fatal breakpoint trap in supervisor mode
[   1.0200695] trap type 1 code 0 eip 0xc0105634 cs 0x9 eflags 0x202 cr2 0 ilevel 0x8 esp 0xc347ce0c
[   1.0200695] curlwp 0xc0e3cd20 pid 0 lid 2 lowest kstack 0xc347a2c0
Stopped in pid 0.2 (system) at  netbsd:breakpoint+0x4:  popl    %ebp
breakpoint(c05548fc,c0c65f80,c0554a6c,c347ce28,c0ee2008,c055aac4,c0599d1a,c347ce
1c,c0525203,c0554a6c) at netbsd:breakpoint+0x4
vpanic(c0554a6c,c347ce28,c347ce64,c01393d1,c0554a6c,c0554a06,c0599d1a,c055aac4,2
c2,1) at netbsd:vpanic+0x13f
kern_assert(c0554a6c,c0554a06,c0599d1a,c055aac4,2c2,1,0,c0ee2160,0,c3507000) at n
etbsd:kern_assert+0x23
xbd_handler(c0ee2008,c0d0e000,6,c0e5b2a8,c347cebc,c011a89f,c0e5b2a8,c347cf14,c0b
19bc0,f9b46430) at netbsd:xbd_handler+0x3c1
xen_intr_biglock_wrapper(c0e5b2a8,c347cf14,c0b19bc0,f9b46430,cc,f9b8a970,0,80000
000,0,c0c259b8) at netbsd:xen_intr_biglock_wrapper+0x1f
evtchn_do_event(6,c347cf14,c347cf58,1,c347cef0,0,c0b0b0c0,c0d0e000,c0d0e000,c0d0
e800) at netbsd:evtchn_do_event+0x10f
do_hypervisor_callback(c347cf14,0,c0110011,c0b00031,c0e60011,c3470011,c0b0b0c0,c
0e3ad40,c347cf74,deadf00d) at netbsd:do_hypervisor_callback+0x15c
Xhypervisor_pvhvm_callback(c0e3cd20,0,c0e3cd20,c0e3cd20,c0102102,c0e3cd20,c03ad7
c0,c0e3cd20,0,c0102031) at netbsd:Xhypervisor_pvhvm_callback+0x67
idle_loop(c0e3cd20,d0e000,c0b22200,0,c010007a,0,0,0,0,0) at netbsd:idle_loop+0xb
f
ds          c3470011
es          c0550011    static_ltree+0x91
fs          31
gs          c3470011
edi         c347ce28
esi         c0554a6c    ostype+0xb04
ebp         c347cde8
ebx         104
edx         1
ecx         6
eax         0
eip         c0105634    breakpoint+0x4
cs          9
eflags      202
esp         c347cde8
ss          11
netbsd:breakpoint+0x4:  popl    %ebp
db{0}> 

>How-To-Repeat:

>Fix: