Repeated panic in obj_getmethods()

[Mark Staudinger]

Hi Folks,

I've seen this panic recently, twice, on two companion servers running  
Varnish-4.1.8 on FreeBSD-11.0

% varnishd -V
varnishd (varnish-4.1.8 revision d266ac5c6)
Copyright (c) 2006 Verdens Gang AS
Copyright (c) 2006-2015 Varnish Software AS

% uname -a
FreeBSD hostname 11.0-RELEASE-p2 FreeBSD 11.0-RELEASE-p2 #0: Mon Oct 24  
06:55:27 UTC 2016      
root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  amd64

Unfortunately I do not have the full backtrace, but here's what I do have.

Oct 16 12:24:47 hostname varnishd[50931]: Child (50932) Last panic at:  
Mon, 16 Oct 2017 12:24:47 GMT "Assert error in obj_getmethods(),  
cache/cache_obj.c line 55:   Condition((oc->stobj->stevedore) != NULL) not  
true. thread = (cache-worker) version = varnish-4.1.8 revision d266ac5c6  
ident =  
FreeBSD,11.0-RELEASE-p2,amd64,-junix,-sfile,-smalloc,-sfile,-hcritbit,kqueue  
now = 3794380.754560 (mono), 1508156686.857677 (real) Backtrace:    
0x433a38: varnishd   0x431821: varnishd   0x431f62: varnishd   0x425f9d:  
varnishd   0x41eb0c: varnishd   0x420d51: varnishd   0x41e8db: varnishd    
0x41e36a: varnishd   0x426155: varnishd busyobj = 0xbf88dbbb60 {   ws =  
0xbf88dbbbf8 {     id = \"bo\",     {s,f,r,e} =  
{0xbf88dbdab0,+4712,0x0,+57480},   },   refcnt = 2,   retries = 0, failed  
= 1, state = 1,   flags = {do_esi, is_gzip},   http_conn = 0xbf88dbde30  
{     fd = 153,     doclose = RX_BODY,     ws = 0xbf88dbbbf8,      
{rxbuf_b, rxbuf_e} = {0xbf88dbdee0, 0xbf88dbe134},     {pipeline_b,  
pipeline_e} = {0xbf88dbe134, 0xbf88dbea65},
Oct 16 12:24:47 hostname kernel: xbf88dbea65},

Varnishd process uptime was near-identical on both servers, and the panics  
occurred at around the same time on both machines, which could potentially  
indicate that the panic was caused either by a particular request, and/or  
some resource-related issue.  Time between panics was approximately 19  
days.

I would welcome any advice about known possible causes for this particular  
assertion failing!

Best Regards,
Mark Staudinger