Re: port-xen/46105: hypervisor-dependent(?) xen crash

[Jeff Rizzo <riz%NetBSD.org@localhost>]

The following reply was made to PR port-xen/46105; it has been noted by GNATS.

From: Jeff Rizzo <riz%NetBSD.org@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: Manuel Bouyer <bouyer%netbsd.org@localhost>
Subject: Re: port-xen/46105: hypervisor-dependent(?) xen crash
Date: Mon, 27 Feb 2012 09:21:13 -0800

 On 2/27/12 3:40 AM, Manuel Bouyer wrote:
 >  
 >  On Mon, Feb 27, 2012 at 01:25:01AM +0000, riz%NetBSD.org@localhost wrote:
 >  >   While creating NetBSD 6.0_BETA/i386 AMIs for Amazon EC2, 2 out of
 >  >   7 did not come up properly.  When I investigated more closely,
 >  >   both the ones which did not come up had a hypervisor version of
 >  >   3.1, while all the others were 3.4.
 >  > 
 >  >   Other details: the instances only had 1 vcpu, so MP should not
 >  >   be a factor.  The regions where the failures occurred (and
 >  >   are more likely, I guess, to have 3.1 hypervisors) were "us-west-1"
 >  >   and "ap-northeast-1".
 >  > 
 >  >   Here is the console log for one of the crashed instances:
 >  > [...]
 >  
 >  Hum, 6.0_BETA 201202250740Z boots fine for me on a NetBSD/amd64 domains0
 >  and 3.1.4 hypervisor. I tested both i386PAE and amd64 domUs.
 >  I fear it's one of the bugs we fixed with recursive table pages;
 >  if so it's going to be hard to work around.
 >  
 >  Do you know if it happens with all Amazon 3.1 hypervisors, or only
 >  some ?
 
 Appears to be only some;  I just tried duplicating the problem (with
 your patch), and of 5 launches, 2 were 3.1, and one of the two crashed. 
 Unfortunately, it did not seem to print the tiny version.  :/
 >  I guess there's no way to restricy a domain to some hypervisor versions
 >  on amazon ?
 
 Nope.
 
 >  
 >  Also, please apply the attached diff if you can reproduce this.
 >  It prints the tiny version of the hypervisor, which can help identifing bugs
 >  present.
 >
 
 It didn't seem to do anything;  maybe I biffed it somehow.
 
 Here is the dmesg from the instance that booted OK:
 
 Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
     2006, 2007, 2008, 2009, 2010, 2011, 2012
     The NetBSD Foundation, Inc.  All rights reserved.
 Copyright (c) 1982, 1986, 1989, 1991, 1993
     The Regents of the University of California.  All rights reserved.
 
 NetBSD 6.0_BETA (EC2) #1: Mon Feb 27 08:36:48 PST 2012
        
 
riz%breadfruit.tastylime.net@localhost:/home/riz/obj.i386/sys/arch/i386/compile/EC2
 total memory = 615 MB
 avail memory = 596 MB
 timecounter: Timecounters tick every 10.000 msec
 mainbus0 (root)
 hypervisor0 at mainbus0: Xen version 3.1
 VIRQ_DEBUG interrupt using event channel 3
 vcpu0 at hypervisor0: Intel(R) Xeon(R) CPU           E5430  @ 2.66GHz,
 id 0x1067a
 xenbus0 at hypervisor0: Xen Virtual Bus Interface
 xencons0 at hypervisor0: Xen Virtual Console Driver
 xencons0: console major 143, unit 0
 xencons0: using event channel 2
 npx0 at hypervisor0: using exception 16
 timecounter: Timecounter "clockinterrupt" frequency 100 Hz quality 0
 timecounter: Timecounter "xen_system_time" frequency 1000000000 Hz
 quality 10000
 Xen clock: using event channel 5
 xenbus0: using event channel 1
 xennet0 at xenbus0 id 0: Xen Virtual Network Interface
 xennet0: MAC address 12:31:3f:00:82:a5
 xennet0: using event channel 6
 xbd0 at xenbus0 id 2049: Xen Virtual Block Device Interface
 xbd0: using event channel 7
 xbd1 at xenbus0 id 2050: Xen Virtual Block Device Interface
 xbd1: using event channel 8
 balloon0 at xenbus0 id 0: Xen Balloon driver
 balloon0: current reservation: 629760 KiB
 xennet0: using RX copy mode
 xbd0: 1024 MB, 512 bytes/sect x 2097152 sectors
 xbd1: 5120 MB, 512 bytes/sect x 10485760 sectors
 Kernelized RAIDframe activated
 balloon0: current reservation: 157440 pages => target: 157440 pages
 boot device: xbd1
 root on xbd1a dumps on xbd1b
 root file system type: ffs
 xbd1: WARNING: cache flush not supported by backend