Pkg xen devel - Apr 2014 - Bug#744159: HVM guest can't be saved/migrated with xl

Package: xen-utils-4.1
Version: 4.1.4-3+deb7u1
Severity: normal

It seems to be impossible to save or migrate HVM guest using the xl
toolstack. Trying to do so hangs the process initiating the action, and
the domU can't be shut down with the 'xl shutdown' command after
this.
'xl destroy' works. The domain keeps running during the save operation,
doesn't get paused for any noticeable time and keeps running fine after
that.

The savefile contains nothing after the configuration dump, which is as
follows:

kernel = '/usr/lib/xen/boot/hvmloader'
builder='hvm'
device_model = '/usr/lib/xen/bin/qemu-dm'
vnclisten="0.0.0.0:6369"
vncpasswd="x"
memory = 256
name = "x"
vcpus = 1
vif = [ 'vifname=x,mac=00:16:3e:00:01:0d,ip=x' ]
disk = [ 'phy:x,hda,w', ]



Stracing xl save revealed where it blocks:

[...]
open("x.sav", O_WRONLY|O_CREAT|O_TRUNC, 0644) = 6
write(6, "Xen saved domain, xl format\n \0 \r"..., 48) = 48
write(6, "\231\1\0\0\nkernel = '/usr/lib/xen/boot"..., 413) = 413
write(2, "Saving to x.sav new xl form"..., 54) = 54
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea162a0) = 0
open("/dev/xen/evtchn", O_RDWR)         = 7
stat("/var/run/xenstored/socket", {st_mode=S_IFSOCK|0600, st_size=0,
...}) = 0
socket(PF_FILE, SOCK_STREAM, 0)         = 9
fcntl(9, F_GETFD)                       = 0
fcntl(9, F_SETFD, FD_CLOEXEC)           = 0
connect(9, {sa_family=AF_FILE, path="/var/run/xenstored/socket"}, 110)
= 0
rt_sigaction(SIGPIPE, {SIG_IGN, [], SA_RESTORER, 0x7f696e28a4f0}, {SIG_DFL, [],
SA_RESTORER, 0x7f696e28a4f0}, 8) = 0
write(9, "\2\0\0\0\0\0\0\0\0\0\0\0.\0\0\0", 16) = 16
write(9, "/local/domain/46/device/suspend/"..., 46) = 46
read(9, "\2\0\0\0\0\0\0\0\0\0\0\0\1\0\0\0", 16) = 16
read(9, "5", 1)                         = 1
rt_sigaction(SIGPIPE, {SIG_DFL, [], SA_RESTORER, 0x7f696e28a4f0}, NULL, 8) = 0
close(9)                                = 0
umask(022)                              = 022
open("/var/lib/xen/suspend_evtchn_46_lock.d", O_RDWR|O_CREAT|O_EXCL,
0666) = 9
umask(022)                              = 022
write(9, "     16096", 10)              = 10
close(9)                                = 0
ioctl(7, EVIOCGVERSION, 0x7fffeea16320) = 56
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea16260) = 0
read(7, "8\0\0\0", 4)                   = 4
write(7, "8\0\0\0", 4)                  = 4
mmap(NULL, 16781312, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) =
0x7f696c3c8000
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea11b50) = 0
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea11b50) = 0
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea11b50) = 2162688
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea11f00) = 0
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea11ab0) = 0
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea11b40) = 1048575
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea11a70) = 0
ioctl(3, SNDCTL_DSP_RESET, 0x7fffeea11a70) = 0
ioctl(7, EVIOCGKEYCODE or EVIOCSKEYCODE, 0x7fffeea11ac0) = 0
read(7, 0x7fffeea11aac, 4)              = ? ERESTARTSYS (To be restarted)
--- SIGINT (Interrupt) @ 0 (0) ---
+++ killed by SIGINT +++

Your message dated Wed, 16 Apr 2014 13:24:29 +0200 (CEST)
with message-id <Pine.LNX.4.44.1404161316520.1164-100000 at hq>
and subject line 
has caused the Debian Bug report #744159,
regarding HVM guest can't be saved/migrated with xl
to be marked as done.

This means that you claim that the problem has been dealt with.
If this is not the case it is now your responsibility to reopen the
Bug report if necessary, and/or fix the problem forthwith.

(NB: If you are a system administrator and have no idea what this
message is talking about, this may indicate a serious mail system
misconfiguration somewhere. Please contact owner at bugs.debian.org
immediately.)


-- 
744159: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=744159
Debian Bug Tracking System
Contact owner at bugs.debian.org with problems
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