port-xen/60228: panic: can't allocate fixed interrupt source

["campbell+netbsd%mumble.net@localhost via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         60228
>Category:       port-xen
>Synopsis:       panic: can't allocate fixed interrupt source
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-xen-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon May 04 15:35:00 +0000 2026
>Originator:     Taylor R Campbell
>Release:        netbsd-10
>Organization:
The NetBSD Foundation
>Environment:
NetBSD 10.1_STABLE (amd64-DOMU_SERVER) #3: Sat Jun 21 13:32:10 UTC 2025
 spz%franklin.NetBSD.org@localhost:/home/netbsd/10/amd64/obj/sys/arch/amd64/compile/amd64-DOMU_SERVER
>Description:
Intermittent failure at boot:

[   1.0000000] Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
[   1.0000000]     2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013,
[   1.0000000]     2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023,
[   1.0000000]     2024, 2025
[   1.0000000]     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 10.1_STABLE (amd64-DOMU_SERVER) #3: Sat Jun 21 13:32:10 UTC 2025
[   1.0000000]  spz%franklin.NetBSD.org@localhost:/home/netbsd/10/amd64/obj/sys/arch/amd64/compile/amd64-DOMU_SERVER
[   1.0000000] total memory = 4096 MB
[   1.0000000] avail memory = 3945 MB
[   1.0000000] mainbus0 (root)
[   1.0000000] hypervisor0 at mainbus0: Xen version 4.18.0_20231116nb0
[   1.0000000] vcpu0 at hypervisor0
[   1.0000000] vcpu0: Intel(R) Xeon(R) CPU           L5630  @ 2.13GHz, id 0x206c2
[   1.0000000] vcpu0: node 0, package 0, core 0, smt 0
[   1.0000000] vcpu1 at hypervisor0
[   1.0000000] vcpu1: Intel(R) Xeon(R) CPU           L5630  @ 2.13GHz, id 0x206c2
[   1.0000000] vcpu1: node 0, package 0, core 0, smt 0
[   1.0000000] vcpu2 at hypervisor0
[   1.0000000] vcpu2: Intel(R) Xeon(R) CPU           L5630  @ 2.13GHz, id 0x206c2
[   1.0000000] vcpu2: node 0, package 0, core 0, smt 0
[   1.0000000] vcpu3 at hypervisor0
[   1.0000000] vcpu3: Intel(R) Xeon(R) CPU           L5630  @ 2.13GHz, id 0x206c2
[   1.0000000] vcpu3: node 0, package 0, core 0, smt 0
[   1.0000000] xenbus0 at hypervisor0: Xen Virtual Bus Interface
[   1.0000000] xencons0 at hypervisor0: Xen Virtual Console Driver
[   1.0000000] WARNING: system needs entropy for security; see entropy(7)
[   2.0000511] xenbus0: can't get state for device/suspend/event-channel (2)
[   2.0000511] xbd0 at xenbus0 id 1: Xen Virtual Block Device Interface
[   2.0000511] xbd1 at xenbus0 id 2: Xen Virtual Block Device Interface
[   2.0000511] panic: can't allocate fixed interrupt source
[   2.0000511] xbd0: 1024 MB, 512 bytes/sect x 2097152 sectors
[   2.0000511] cpu3: Begin traceback...
[   2.0000511] xbd0: backend features 0x1<CACHE-FLUSH>
[   2.0000511] vpanic() at netbsd:vpanic+0x177
[   2.0100593] panic() at netbsd:panic+0x3c
[   2.0100593] event_set_handler() at netbsd:event_set_handler+0x4ad
[   2.0100593] intr_establish_xname() at netbsd:intr_establish_xname+0x9a
[   2.0100593] xbd_xenbus_resume() at netbsd:xbd_xenbus_resume+0x2c7
[   2.0100593] xbd_xenbus_attach() at netbsd:xbd_xenbus_attach+0x3d0
[   2.0100593] config_attach_internal() at netbsd:config_attach_internal+0x197
[   2.0100593] config_found() at netbsd:config_found+0xc1
[   2.0100593] xenbus_probe_device_type() at netbsd:xenbus_probe_device_type+0x3d9
[   2.0100593] xenbus_probe_frontends.isra.0() at netbsd:xenbus_probe_frontends.isra.0+0xa4
[   2.0100593] xenbus_probe() at netbsd:xenbus_probe+0x33
[   2.0100593] xenbus_probe_init() at netbsd:xenbus_probe_init+0x8a
[   2.0100593] cpu3: End traceback...
[   2.0100593] fatal breakpoint trap in supervisor mode
[   2.0100593] trap type 1 code 0 rip 0xffffffff8022e975 cs 0xe030 rflags 0x202 cr2 0 ilevel 0 rsp 0xffff8c0144a099a0
[   2.0100593] curlwp 0xffff8c000812db40 pid 0.99 lowest kstack 0xffff8c0144a052c0
Stopped in pid 0.99 (system) at netbsd:breakpoint+0x5:  leave
breakpoint() at netbsd:breakpoint+0x5
vpanic() at netbsd:vpanic+0x177
panic() at netbsd:panic+0x3c
event_set_handler() at netbsd:event_set_handler+0x4ad
intr_establish_xname() at netbsd:intr_establish_xname+0x9a
xbd_xenbus_resume() at netbsd:xbd_xenbus_resume+0x2c7
xbd_xenbus_attach() at netbsd:xbd_xenbus_attach+0x3d0
config_attach_internal() at netbsd:config_attach_internal+0x197
config_found() at netbsd:config_found+0xc1
xenbus_probe_device_type() at netbsd:xenbus_probe_device_type+0x3d9
xenbus_probe_frontends.isra.0() at netbsd:xenbus_probe_frontends.isra.0+0xa4
xenbus_probe() at netbsd:xenbus_probe+0x33
xenbus_probe_init() at netbsd:xenbus_probe_init+0x8a
ds          ffff
es          3
fs          e02b
gs          9950
rdi         0
rsi         ffff8c0144a0970c
rbp         ffff8c0144a099a0
rbx         ffff8c00083fb000
rdx         1
rcx         ffffffffffffff
rax         800000000000000
r8          0
r9          0
r10         0
r11         fffffffe
r12         ffffffff8058c348    ostype+0x178c
r13         ffff8c0144a099e8
r14         104
r15         d
rip         ffffffff8022e975    breakpoint+0x5
cs          e030
rflags      202
rsp         ffff8c0144a099a0
ss          e02b
netbsd:breakpoint+0x5:  leave
db{3}> 

>How-To-Repeat:
reboot a few times
>Fix:
Yes, please!