- Devel - libvirt List Archives

[Libvir] [RFC][PATCH 0/2] NUMA memory and topology patches
by beth kon 25 Sep '07

25 Sep '07

I am reposting an updated patch for accessing NUMA cell available memory, and posting the initial patch for accessing NUMA topology information. Again, this code is primarily untested. I am looking for comments in parallel with the testing I will begin tomorrow. These patches prereq Daniel Veillard's initial framework patch: https://www.redhat.com/archives/libvir-list/2007-September/msg00069.html [PATCH 1/2] - add capability to access free memory information on each NUMA cell. [PATCH 2/2] - add capability to access topology information (cell to cpu mapping) for each numa cell. I have not yet added the full node available memory API call that was discussed on the list. As I understand the NUMA code is more urgent. If you would like to get this code in too, I can create another patch for that. My focus for the moment is testing. Signed-off-by: Beth Kon (eak(a)us.ibm.com) -- Elizabeth Kon (Beth) IBM Linux Technology Center Open Hypervisor Team email: eak(a)us.ibm.com

1 0

[Libvir] RFC PATCH - Initial NodeGetCellsFreeMemory patch
by beth kon 24 Sep '07

24 Sep '07

Here is my first pass at a patch for accessing the available memory associated with each NUMA cell through libvirt. The initial framework patch provided by Daniel Veillard is a prereq of this patch: https://www.redhat.com/archives/libvir-list/2007-September/msg00069.html I have not yet tested this. I'm just distributing for comments. A few comments/questions: 1) I think I got the versioning stuff right but that deserves a close look. 2) In Daniel's patch, libvirt.h and libvirt.h.in were identical. I assumed the patch would be before running autogen.sh, and only contain changes in libvirt.h.in, so that's how I did mine. Let me know if I misunderstand something here. 3) I had to put #ifdef PROXY around calls to virXenErrorFunc in xenHypervisorNodeGetCellsFreeMemory to get this to build. I haven't figured out how the proxy code works so am not sure if this is the right approach. -- Elizabeth Kon (Beth) IBM Linux Technology Center Open Hypervisor Team email: eak(a)us.ibm.com

3 6

[Libvir] Remotely starting a fully-virtualized guest
by Meng Kuan 24 Sep '07

24 Sep '07

Hi, I am trying to start a fully virtualized guest called "full1" remotely. The connection URI I am using is "xen+ssh://root@dell1/". (Note that I am able to start/stop/resume/shutdown para-virtualized guests without any problems with this connection URI.) The XML definition for the fully virtualized guest is this: <domain type='xen'> <name>full1</name> <os> <type>hvm</type> <loader>/usr/lib/xen/boot/hvmloader</loader> <boot dev='hd'/> </os> <memory>1048576</memory> <vcpu>2</vcpu> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <features> <acpi/> <apic/> <pae/> </features> <clock offset='utc'/> <devices> <emulator>/usr/lib64/xen/bin/qemu-dm</emulator> <interface type='bridge'> <source bridge='xenbr0'/> <script path='vif-bridge'/> </interface> <disk type='file' device='disk'> <driver name='file'/> <source file='/xen/full1.img'/> <target dev='hda'/> </disk> <graphics type='vnc' port='5904'/> </devices> </domain> The guest failed to start up and this is what I found in the xend.log file: [2007-09-24 18:55:46 xend.XendDomainInfo 4176] DEBUG (XendDomainInfo: 190) XendDomainInfo.create(['vm', ['name', 'full1'] , ['memory', '1024'], ['maxmem', '1024'], ['vcpus', '2'], ['on_poweroff', 'destroy'], ['on_reboot', 'restart'], ['on_crash ', 'restart'], ['image', ['hvm', ['kernel', '/usr/lib/xen/boot/ hvmloader'], ['device_model', '/usr/lib64/xen/bin/qemu-dm '], ['vcpus', '2'], ['boot', 'c'], ['acpi', '1'], ['apic', '1'], ['pae', '1'], ['usb', '1'], ['vnc', '1'], ['vncdisplay' , '4']]], ['device', ['vbd', ['dev', 'hda:disk'], ['uname', 'file:/ xen/full1.img'], ['mode', 'w']]], ['device', ['vif', ['bridge', 'xenbr0'], ['script', 'vif-bridge'], ['type', 'ioemu']]]]) [2007-09-24 18:55:46 xend.XendDomainInfo 4176] DEBUG (XendDomainInfo: 296) parseConfig: config is ['vm', ['name', 'full1' ], ['memory', '1024'], ['maxmem', '1024'], ['vcpus', '2'], ['on_poweroff', 'destroy'], ['on_reboot', 'restart'], ['on_cras h', 'restart'], ['image', ['hvm', ['kernel', '/usr/lib/xen/boot/ hvmloader'], ['device_model', '/usr/lib64/xen/bin/qemu-d m'], ['vcpus', '2'], ['boot', 'c'], ['acpi', '1'], ['apic', '1'], ['pae', '1'], ['usb', '1'], ['vnc', '1'], ['vncdisplay ', '4']]], ['device', ['vbd', ['dev', 'hda:disk'], ['uname', 'file:/ xen/full1.img'], ['mode', 'w']]], ['device', ['vif', ['bridge', 'xenbr0'], ['script', 'vif-bridge'], ['type', 'ioemu']]]] [2007-09-24 18:55:46 xend.XendDomainInfo 4176] DEBUG (XendDomainInfo: 397) parseConfig: result is {'shadow_memory': None, 'start_time': None, 'uuid': None, 'on_crash': 'restart', 'on_reboot': 'restart', 'localtime': None, 'image': ['hvm', [' kernel', '/usr/lib/xen/boot/hvmloader'], ['device_model', '/usr/lib64/ xen/bin/qemu-dm'], ['vcpus', '2'], ['boot', 'c'], ['acpi', '1'], ['apic', '1'], ['pae', '1'], ['usb', '1'], ['vnc', '1'], ['vncdisplay', '4']], 'on_poweroff': 'destroy', 'bootloader_args': None, 'cpus': None, 'name': 'full1', 'backend': [], 'vcpus': 2, 'cpu_weight': None, 'features': None, 'vcpu_avail': None, 'memory': 768, 'device': [('vbd', ['vbd', ['dev', 'hda:disk'], ['uname', 'file:/xen/full1.img'], [' mode', 'w']]), ('vif', ['vif', ['bridge', 'xenbr0'], ['script', 'vif- bridge'], ['type', 'ioemu']])], 'bootloader': None, 'cpu': None, 'maxmem': 768} [2007-09-24 18:55:46 xend.XendDomainInfo 4176] DEBUG (XendDomainInfo: 1264) XendDomainInfo.construct: None [2007-09-24 18:55:46 xend.XendDomainInfo 4176] DEBUG (XendDomainInfo: 1296) XendDomainInfo.initDomain: 91 1.0 [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: boot, val: c [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: fda, val: None [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: fdb, val: None [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: soundhw, val: None [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: localtime, val: None [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: serial, val: None [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: std-vga, val: None [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: isa, val: None [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: vcpus, val: 2 [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: acpi, val: 1 [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: usb, val: 1 [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: usbdevice, val: None [2007-09-24 18:55:46 xend 4176] DEBUG (image:329) args: k, val: None [2007-09-24 18:55:46 xend.XendDomainInfo 4176] ERROR (XendDomainInfo: 202) Domain construction failed Traceback (most recent call last): File "/usr/lib64/python2.4/site-packages/xen/xend/ XendDomainInfo.py", line 195, in create vm.initDomain() File "/usr/lib64/python2.4/site-packages/xen/xend/ XendDomainInfo.py", line 1309, in initDomain self.info['device']) File "/usr/lib64/python2.4/site-packages/xen/xend/image.py", line 45, in create return findImageHandlerClass(imageConfig)(vm, imageConfig, deviceConfig) File "/usr/lib64/python2.4/site-packages/xen/xend/image.py", line 75, in __init__ self.configure(imageConfig, deviceConfig) File "/usr/lib64/python2.4/site-packages/xen/xend/image.py", line 272, in configure self.dmargs += self.configVNC(imageConfig) File "/usr/lib64/python2.4/site-packages/xen/xend/image.py", line 383, in configVNC ret += ['-vnc', '%d' % vncdisplay] TypeError: int argument required [2007-09-24 18:55:46 xend.XendDomainInfo 4176] DEBUG (XendDomainInfo: 1463) XendDomainInfo.destroy: domid=91 [2007-09-24 18:55:46 xend.XendDomainInfo 4176] DEBUG (XendDomainInfo: 1471) XendDomainInfo.destroyDomain(91) [2007-09-24 18:55:46 xend 4176] ERROR (SrvBase:88) Request create failed. Traceback (most recent call last): File "/usr/lib64/python2.4/site-packages/xen/web/SrvBase.py", line 85, in perform return op_method(op, req) File "/usr/lib64/python2.4/site-packages/xen/xend/server/ SrvDomainDir.py", line 82, in op_create raise XendError("Error creating domain: " + str(ex)) XendError: Error creating domain: int argument required It seems that xend got a string instead of an integer for the vnc port. I modified the file "image.py" at line 383 from this ret += ['-vnc', '%d' % vncdisplay] to this: ret += ['-vnc', '%s' % vncdisplay] Restarted xend for the change to take effect and then try starting the guest again. This time the guest gets created but its state does not change to "running". # xm list Name ID Mem(MiB) VCPUs State Time(s) Domain-0 0 451 2 r----- 356.7 full1 88 773 1 ------ 0.0 I removed the following vnc line from the xml definition and try again: <graphics type='vnc' port='5904'/> The guest gets created but again its state is not "running". According to xml format documentation the <graphics> tag is required. At this point I am stumped. Any ideas what else I can try? cheers, mengkuan

2 2

[Libvir] PATCH 0/5: Rework the configure script
by Daniel P. Berrange 24 Sep '07

24 Sep '07

The following series of patches re-work the configure to solve a number of issues. I'll describe each one alongside its respective patch... Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

6 28

Re: [Libvir] RFC PATCH - Initial NodeGetCellsFreeMemory patch
by beth kon 21 Sep '07

21 Sep '07

oops... meant to post to list as well beth kon wrote: > Daniel Veillard wrote: > >> On Thu, Sep 20, 2007 at 05:10:49PM -0400, beth kon wrote: >> >> >>> Here is my first pass at a patch for accessing the available memory >>> associated with each NUMA cell through libvirt. >>> >> >> Thanks ! >> >> > Thanks for the quick comments! > >>> +struct xen_v2s4_availheap { >>> + uint32_t min_bitwidth; /* Smallest address width (zero if don't >>> care). */ >>> + uint32_t max_bitwidth; /* Largest address width (zero if don't >>> care). */ >>> >> >> I'm a bit puzzled by those 2 fields I still wonder what it is about :-) >> >> >> > I was puzzled too! These fields are related to the case when 32 bit > guests need to reserve certain ranges of memory for DMA, for example. > I checked with Ryan and he assured me we don't need to worry about > those fields for these purposes. > >>> + int32_t node; /* NUMA node (-1 for sum across all nodes). */ >>> + uint64_t avail_bytes; /* Bytes available in the specified region. */ >>> +}; >>> + >>> +typedef struct xen_v2s4_availheap xen_v2s4_availheap; >>> + >>> >> [...] >> >> > What does [...] mean? :-) > >> >> >>> +xenHypervisorNodeGetCellsFreeMemory(virConnectPtr conn, long long >>> *freeMems, >>> + int startCell, int maxCells) >>> { >>> - if ((conn == NULL) || (freeMems == NULL) || (nbCells < 0)) >>> - return -1; >>> + xen_op_v2_sys op_sys; >>> + int i, ret, nbCells; >>> + virNodeInfo nodeInfo; >>> + virNodeInfoPtr nodeInfoPtr = &nodeInfo; >>> + xenUnifiedPrivatePtr priv; >>> + >>> + if ((conn == NULL) || (freeMems == NULL) || (maxCells < 0)) >>> + return -1; >>> >> >> Hum, actually, that would catch the (maxCells == -1) so that won't work >> and won't catch maxCells == 0 which could lead to a segfault. Maybe >> (maxCells == 0) || (maxCells < -1) should be used instead. >> >> >> > Yes, you're right. I added maxcells = -1 and startCell as an > afterthought, and it shows! > >>> + /* get actual number of cells */ >>> + if (xenDaemonNodeGetInfo(conn, nodeInfoPtr)) { >>> >> >> Hum, since the number of cells is static, maybe this should be stored >> permanently in a variable on init. The xenDaemon RPC will be orders >> of magnitude >> more expensive than the direct hypercall below. >> >> >> >>> + virXenError(VIR_ERR_XEN_CALL, " cannot determine actual number of >>> cells", 0); >>> + return -1; >>> + } >>> + nbCells = nodeInfoPtr->nodes; >>> + >>> + if (maxCells > nbCells) >>> + maxCells = nbCells; >>> >> >> >> > I wondered about that. Would you like me to make that change as part > of this patch? > >> Hum ... maxCells is the number of entries in the array, I'm afraid >> you will >> need 2 counters or I misunderstood the way the API works (possible :-), >> I would fill in freeMems[] starting at index 0 for startCell, and >> going up. >> That feels more coherent than leaving uninitialized values at the >> start of >> the array: >> >> for (i = startCell, j = 0;(i < nbCells) && (j < maxCells);i++,j++) { >> op_sys.u.availheap.node = i; >> ret = xenHypervisorDoV2Sys(priv->handle, &op_sys); >> if (ret < 0) >> return(-1); >> freeMems[j] = op_sys.u.availheap.avail_bytes; >> } >> return (j); >> >> >> > Yes, right again! > > Thanks so much for the great feedback! > -- Elizabeth Kon (Beth) IBM Linux Technology Center Open Hypervisor Team email: eak(a)us.ibm.com

2 1

[Libvir] How to deploy Virtual Machine via libvirt
by Omer Khalid 21 Sep '07

21 Sep '07

Hi, I have been using libvirt in my python software for a while just to get deployed domain information. Usually I create a xen configuration file with all the parameters and trigger a "xm create -f file" command to deploy the VM. The problem I have noticed since some time is that as this command is forwarded from Python to Xen, and no error code is returned; I loose track if the domain deployment request fails which is rare but happens. So I thought to use libvirt for virtual machine deployment, and wondered if there are python bindings which I could use. I also try to look up for some kind of small example code to deploy a VM via libvirt on the libvirt site but didn't succeed to find. Can any body help me out with their experience? Thanks, Omer -- ---------------------------------------------------------- CERN – European Organization for Nuclear Research, IT Department, CH-1211 Geneva 23, Switzerland Phone: +41 (0) 22 767 2224 Fax: +41 (0) 22 766 8683 E-mail : Omer.Khalid(a)cern.ch Homepage: http://cern.ch/Omer.Khalid

2 3

[Libvir] Java bindings
by Tóth István 21 Sep '07

21 Sep '07

Hello! A development version of the java bindings I've been working on are available at : http://tiger.3ginformatika.hu/java-libvirt.tgz I'd appreciate your feedback on it. Building: Have java/gcc set up correctly through alternatives ( I use jpackage sun java 1.5.0 on Fedora 7 x86_64) Fix the include path in jni/Makefile run build.sh You should have the .so and .jar files built, and see the output from the basic test program. Using: See the test in build.sh Note: It's meant to be a thin translation layer on top of libvirt. The object model is similar to the python one. All error handling is done exclusively through exceptions. No documentation yet, but It's pretty self-explanatory. The build system is very primitive, I just hacked together something to build it outside my eclipse devel environment. The bindings are pretty complete, but minimally tested. License is LGPL. Best regards István

3 6

[Libvir] [PATCH] add no_tty flag for ssh
by Richard W.M. Jones 21 Sep '07

21 Sep '07

This patch adds an extra no_tty=1 flag to the connection URI. This stops ssh from asking for a password if it can't log in automatically. Typical use-case for this is in graphical programs where if ssh asks for a password it would cause the GUI program to hang. Example: $ virsh -c xen+ssh://xxx/ list rjones@xxx's password: Permission denied, please try again. rjones@xxx's password: Permission denied, please try again. rjones@xxx's password: Permission denied (publickey,gssapi-with-mic,password). libvir: Remote error : Connection reset by peer error: failed to connect to the hypervisor error: no valid connection $ virsh -c xen+ssh://xxx/?no_tty=1 list Permission denied (publickey,gssapi-with-mic,password). libvir: Remote error : Connection reset by peer error: failed to connect to the hypervisor error: no valid connection Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903

3 8

[Libvir] PATCH: Do proper URI parsing for QEMU driver
by Daniel P. Berrange 21 Sep '07

21 Sep '07

The QEMU driver doesn't cope with URI parameters appended to the end of a path since it is just doing strcmp on the URI. This patch makes it use libxml's URI parsing code Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

2 2

[Libvir] [PATCH] detect path of dnsmasq, brctl
by Richard W.M. Jones 20 Sep '07

20 Sep '07

I have found 3 bugs in libvirtd in the way that it runs the external programs dnsmasq and brctl. Bug (1) is that it searches the $PATH to find dnsmasq. This is normally OK when libvirtd is launched from start-up scripts, but it's not very helpful if you run libvirtd by hand because likely-as-not your path won't contain /usr/sbin (the normal location of dnsmasq). Bug (2) is that if libvirtd can't execvp dnsmasq, then it doesn't fail in any obvious way. Bug (3) is that the path to brctl is hard-coded. This patch fixes bugs (1) & (3), but does not fix bug (2). Firstly configure has been changed so that it searches for dnsmasq and brctl programs in the usual places. If it find them then it generates a config.h file which looks like this: -------------------- /* Location or name of the brctl program (see bridge-utils) */ #define BRCTL "/usr/sbin/brctl" /* Location or name of the dnsmasq program */ #define DNSMASQ "/usr/sbin/dnsmasq" -------------------- If it doesn't find them then it just includes the program names, not full paths: -------------------- /* Location or name of the brctl program (see bridge-utils) */ #define BRCTL "brctl" /* Location or name of the dnsmasq program */ #define DNSMASQ "dnsmasq" -------------------- The code continues to use execvp to actually run the programs, so if the program names contain '/' then the absolute paths are used directly, otherwise execvp will do a shell-like search for the program along $PATH. Please nota bene the change to the spec file. Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903

2 2

Re: [Libvir] PATCH: Explicit detection of KVM version
by Daniel P. Berrange 20 Sep '07

20 Sep '07

On Thu, Sep 20, 2007 at 10:45:03AM +0200, Gerd Hoffmann wrote: > Daniel P. Berrange wrote: > > Before starting any guest, the QEMU driver needs to figure out what version > > of QEMU is in use & thus determine whether it supports particular command > > line flags. We currently do that just by calling /usr/bin/qemu, since all > > the various qemu-system-XXX binaries share the same syntax. The only problem > > is that qemu-kvm does not neccessarily match the version of qemu installed. > > So we detect QEMU version 0.8.2, but KVM is 0.9.0 based. The result is that > > we pass the wrong style VNC argument to KVM & it fails to start. The second > > problem is that even if you only ever want to run KVM guests, you still have > > to have KVM itself installed. > > We have the same problem if the domain.xml has > "<emulator>/path/to/qemu-foo</emulator>" specified, which I think isn't > addressed by this patch ... Nope it is not addressed. I think maybe instead of detecting once for QEMU and KVM for the QEMU driver as whole, I'll move the flags into the per-VM data structure. This will have extra overhead, since for each distinct VM we'll have todo a test launch of QEMU, but VM creation is not a performance bottleneck so I don't think its an issue. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

1 1

[Libvir] PATCH: Remove Xen Proxy driver
by Daniel P. Berrange 20 Sep '07

20 Sep '07

Since the previous patch allows the remote daemon to serve all the functions of the current Xen Proxy driver, this patch simply removes the Xen proxy and its driver. $ diffstat .hg/patches/remote-proxy Makefile.am | 2 a/proxy/.cvsignore | 5 a/proxy/Makefile.am | 19 a/proxy/libvirt_proxy.c | 852 ------------------------------------ a/src/proxy_internal.c | 1124 ------------------------------------------------ a/src/proxy_internal.h | 116 ---- src/Makefile.am | 1 src/xen_unified.c | 51 -- src/xen_unified.h | 9 9 files changed, 15 insertions(+), 2164 deletions(-) Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

3 5

[Libvir] [PATCH] Add support for virConnectGetHostname and virConnectGetURI for qemu
by Richard W.M. Jones 20 Sep '07

20 Sep '07

Specifically this just adds support for virConnectGetHostname on qemu:/// URIs. Because of the way that the qemu driver now works, calls to virConnectGetURI are answered by the remote driver before the qemu driver ever sees them, so they have worked all along. Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903

3 3

[Libvir] PATCH: Explicit detection of KVM version
by Daniel P. Berrange 20 Sep '07

20 Sep '07

Before starting any guest, the QEMU driver needs to figure out what version of QEMU is in use & thus determine whether it supports particular command line flags. We currently do that just by calling /usr/bin/qemu, since all the various qemu-system-XXX binaries share the same syntax. The only problem is that qemu-kvm does not neccessarily match the version of qemu installed. So we detect QEMU version 0.8.2, but KVM is 0.9.0 based. The result is that we pass the wrong style VNC argument to KVM & it fails to start. The second problem is that even if you only ever want to run KVM guests, you still have to have KVM itself installed. This patch tweaks the feature/version detection so we do separate detection just for KVM. With this applied I can successfully start KVM guests if the QEMU version is different, or even if QEMU is not installed. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

3 2

[Libvir] [PATCH] virConnectNumOfDefinedDomains should set virterror if cannot connect to xend
by Richard W.M. Jones 19 Sep '07

19 Sep '07

As well as $SUBJECT this also adds a comment so that the apparent lack of error in another part of the code is clear. Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903

3 2

[Libvir] PATCH: Cleanup conditionals from proxy driver in Xen code
by Daniel P. Berrange 19 Sep '07

19 Sep '07

The various xen drivers have alot of their code conditionally compiled using #ifdef PROXY to avoid functions when built into the proxy. Without the proxy this is no longer needed. There are a couple of functions that were only used by the proxy & so can go completely. $ diffstat .hg/patches/proxy-cpp-cleanup xen_internal.c | 24 +------------------ xend_internal.c | 70 +++----------------------------------------------------- xml.c | 2 - xs_internal.c | 59 +---------------------------------------------- 4 files changed, 8 insertions(+), 147 deletions(-) Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

2 1

[Libvir] PATCH: Allow control over UNIX socket perms & group in libvirtd
by Daniel P. Berrange 19 Sep '07

19 Sep '07

When I submitted the patches for PolicyKit[1] support a few weeks back Rich suggested that we should have the ability to set UNIX socket permissions and group ownership regardless. So this patch adds that ability. The default setting is still, group=root, and mode=0700 for R/W socket and mode=0777 for the R/O socket. It is possible to override this via the config file eg, Don't allow R/O monitoring unix_sock_ro_perms="0700" eg, Allow any user in 'admin' group to manage VMs unix_sock_group="admin" unix_sock_rw_perms="0770" eg, Allow anyone todo anything unix_sock_rw_perms="0777" NB, the fchgrp, and fchown syscalls don't have any effect on sockets, so to set the group ownership & desired mode, I have to play games with the setgid() and umask() calls prior to bind(), and then restore them to their original values. NB, the virConf apis don't seem to recognise Octal numbers when parsing the config file, so I've used strings for the permissions. Not a big deal really unless someone desperately wants to fix the config file parser... Dan. [1] A new set of patches will be forthcoming soon... -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

2 3

[Libvir] PATCH: Avahi advertisement for libvirtd
by Daniel P. Berrange 19 Sep '07

19 Sep '07

This is a serious patch at supporting Avahi advertisement of the libvirtd service. - configure by default will probe to see if avahi is available and if found will enable appropriate code. --with-avahi will force error if not found --without-avahi will disable it with no checking - HAVE_AVAHI is defined in config.h if avahi is found & used to conditionally enable some code in qemud/qemud.c - HAVE_AVAHI is also a Makefile conditional to enable compilation of the mdns.c and mdns.h files. A little makefile rearrangement was needed to make sure variables like EXTRA_DIST were defined before we appended to them with += - The code in mdns.c contains all the support for dealing with the Avahi APIs. - The primary Avahi API is horribily complicated for day-to-day use in application code, exposing far too much of the event loop and state machine. So we expose a simplified API to libvirt in mdns.h - We fully support the Avahi state machine, so you can start libvirt even if Avahi is not running on the machine. If you later start Avahi, then libvirt will automatically detect & register with it. Likewise if you stop Avahi we handle that gracefully by shutting down our internal mdns support & waiting for avahi to restart. NB this does require that the DBus system bus daemon is running. This is a limitation of the current Avahi client library & not our use of it. It is expected this will be fixed in future avahi releases. - The Avahi client library is basically a shim which talks to the Avahi daemon using DBus system daemon. The DBus stuff doesn't leak out of the Avahi APIs - it is loosely couple - all we need do is provide Avahi with an event loop implementation which was surprisingly easy. The libvirtd daemon does now indirectly link with DBus, but I don't see any problem with this. Don't want it - then use --without-avahi - We advertise a service name of _libvirt._tcp The IETF draft recommends use of the name from /etc/services associated with your app. There is a way to register official Avahi services names. We don't have an /etc/service name registered either though. - If TLS is *not* enabled, we advertise _libvirt._tcp with a port number of 0. The use of a port number 0 is explicitly allowed by the IETF draft docs - see [1] "8. Flagship Naming". If seeing the _libvirt._tcp service with a port of 0, then clients should figure out some way to to tunnel to the UNXI domain socket on the advertised machine. The tunnel mechanism is undefined, though SSH is the obvious choice. If TLS is enabled, then we use getsockname() to fetch the actual port number we're listening on for the TLS enabled socket. This plays nice with admins ability to override the port number. Clients can still of course choose to tunnel instead of use TLS. NB. we explicitly refuse to advertise the non-TLS port. - The default service name we advertise is 'Virtualization Host %h' where '%h' is the short hostname (ie without domain name). This has to be less than 63 characters & stripping domain name is usual practice, since this is implicit from the mdns domain you are browsing. This can be overridden with mdns_name="Blah" in the libvirtd.conf configuration file. Service names *must* be unique in the LAN. If a name clashes, then avahi appends junk like #1, #2, #3... until it is unique. - Even when compiled in, use of Avahi mdns can be disabled by setting the mdns_adv=0 config file parameter in /etc/libvirt/libvirtd.conf - This patch does not advertise any per-VM VNC server instances, but I have prepared the APIs in mdns.h to be ready to support that with minimal effort. A pre-requisite for this is an extension to the driver API to get async signals when VMs start & stop, since making the daemon poll hypervisors will suck big time. When implemented each VM will be its own mdns 'group' and the VNC server associated with it will be the 'service' advertised in that group. Having applied this patch & started the daemon, if /etc/init.d/avahi-daemon is running, you should see the service advertised on the LAN. As mentioned earlier if you start Avahi daemon after libvirt it should detect this too. You can verify by running the following on another box on the same local LAN segment. $ avahi-browse --resolve _libvirt._tcp When you start libvirtd on the other box the avahi-browse should print out a record. It should look like this: + eth0 IPv4 Virtualization Host avocado _libvirt._tcp local = eth0 IPv4 Virtualization Host avocado _libvirt._tcp local hostname = [avocado.local] address = [10.13.7.48] port = [16514] txt = ["org.freedesktop.Avahi.cookie=3025088350"] If you've not configured TLS, then port will be '0' instead of 16514. So that brings me nicely onto the main outstanding issue. Notice the hostname is 'avocado.local' - this is the standard mdns practice for zero-conf DNS hostnames. If you're /etc/nsswitch.conf is setup correctly the name avocado.local will actually resolve to the IP address you see there of '10.13.7.48' (well s/avocado/your hostname/ of course). Well, x509 certificates include a FQDN in them & the client is expected to validate the certificate hostname against the hostname it connected to. Now my FQDN is avocado.virt.boston.redhat.com which is obviously going to not validate against avocado.local. There're a couple of ways around this issue I can come up with so far - Recommend that the client try to reverse-DNS the 'address' field from the mdns advertisement. If reverse-DNS is working, 10.13.7.48 will be transformed into 'avocado.virt.boston.redhat.com' which the client can then connect to. - Add TXT record containing the hostname associated with the certificate. If the client were to use this record, then obviously any validation of it against the resulting certificate is sort-of pointless, since both came from the server. The first approach rather had this drawback too. - Advertise the records in the real domain 'virt.boston.redhat.com' instead of '.local'. Not been able to make this work. - Simply don't bother validating the remote hostname against the server certificate cname. ie, take the position that if using zero-conf then you already have some implicit level of trust in your LAN and validating the cert against the CA cert is sufficient & hostname matching can be ignored. These are all mildy abusing mdns / zeroconf, but then x509 certificates don't really fit into the model of 'zero conf' in the first place. If people want true zero-conf then the (SSH) tunnel is better (and always available), but if they've setup certificates they should still be allowed to use zero-conf to at least locate hosts. So mildly abusing the rules is reasonable IMHO. Personally I'm tending towards the latter approach. Regards, Dan. [1] http://files.dns-sd.org/draft-cheshire-dnsext-dns-sd.txt -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

3 5

[Libvir] PATCH: Allow updating of timer & file handle event watches
by Daniel P. Berrange 19 Sep '07

19 Sep '07

The forthcoming patch to add Avahi support requires a couple of enhancements to our event loop to support integration with Avahi's event callback needs - Ability to update the event mask for a pre-existing file handle watch - Ability to change the frequency of a timer watch - Ability to have a timer which fires immediately - Ability to disable events on a timer watch The first point was trivial - just change the 'events' flag we have recorded in the virEventHandle struct. The second point was also trivial - just change the period of the timer as recorded in virEventTimer struct. The last two points were more tricky, but doable. To fire a timer immediately I tweaked the logic so that it allows a frequency of '0'. Obviously to avoid spinning 100%, the app should unregister the timer once it has fired the desired number of times (usually 1). To disable a timer temporarily I allow the use of '-1' in the frequency. THe code had a bad mix of terminology using a 'timer' and 'timeout' field in the virEventTimer struct which confused me no end. So I renamed the 'timeout' field to 'frequency' which reflects its actual purpose. Finally, when building with debugging, the event loop can generate alot of data, so I added a EVENT_DEBUG macro to the file which prefixes EVENT: on all debug output so allow easy filtering. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

2 3

[Libvir] PATCH: Disable automake portability warnings
by Daniel P. Berrange 19 Sep '07

19 Sep '07

The latest automake has a nasty habit of complaining about use of GNU Make features such as wildcards. We use these extensively in the tests/ directory since there are so many test datafiles, listing them explicitly is a waste of time. The attached patch passes the -Wno-portability flag to automake to make it keep quiet. NB, to do this required a bit of a re-working of the automake/autoconf initialization stuff. Our current configure script uses AC_INIT and AM_INIT_AUTOMAKE in the so called 'legacy style'. To quote the automake manual [quote] If your `configure.ac' has: AC_INIT([src/foo.c]) AM_INIT_AUTOMAKE([mumble], [1.5]) you can modernize it as follows: AC_INIT([mumble], [1.5]) AC_CONFIG_SRCDIR([src/foo.c]) AM_INIT_AUTOMAKE [/quote] This re-arrangement is valid on any non-jurassic era automake & only impacts developers running autogen.sh - not end users running the configure script itself. The one complication is that the version given to AC_INIT must be a literal, but we currently used an environment variable. So m4 black-magic gets around this problem. I also killed LIBVIRT_VERSION_EXTRA since it is not referenced anywhere in the source tree. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

2 2

[Libvir] Network blocking issue
by Shuveb Hussain 17 Sep '07

17 Sep '07

Hi, I observed this while using the python bindings and accessing a remote host with libvirt: >>> import libvirt >>> c = libvirt.open('xen://veetee/') >>> c.getInfo() ['i686', 2021, 2, 1864, 1, 1, 2, 1] >>> c.getInfo() ['i686', 2021, 2, 1864, 1, 1, 2, 1] # remove network cable from remote machine now >>> c.getInfo() # blocks forever.... What is the problem here and is there a solution to this? I am running FC7 and here is the version info from virsh: virsh # version Compiled against library: libvir 0.3.2 Using library: libvir 0.3.2 Using API: Xen 3.0.1 Running hypervisor: Xen 3.1.0 I observed this for more than 10 mins, it was still hung. Thanks in advance! -- Shuveb Hussain. Money has nothing to do with Happiness, But, Poverty has a lot to do with Sorrow. Company: www.binarykarma.com Blog: www.binarykarma.org

4 9

[Libvir] NUMA topology calls
by beth kon 17 Sep '07

17 Sep '07

Daniel, We agreed that xenHypervisorGetCapabilities will call a xend_internal.c function to get the topology through xend. Was your intent to extend xenDaemonNodeGetInfo or have a new function, such as xenDaemonNodeGetTopology? I assumed a new function would be cleaner, but you didn't include such a function in your patch so I'm not sure if you had some other idea. -- Elizabeth Kon (Beth) IBM Linux Technology Center Open Hypervisor Team email: eak(a)us.ibm.com

2 1

[Libvir] PATCH: Prevent zombie ssh tunnels
by Daniel P. Berrange 17 Sep '07

17 Sep '07

I noticed that when using the SSH tunnel for the remote driver I ended up with alot of zombie SSH processes. We simply forgot to waitpid() on the child when a connection attempt failed, or when shutting down an open remote connection. Attached is a possible patch Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

4 10

[Libvir] RFC: Broadcast our presence with avahi
by Daniel P. Berrange 14 Sep '07

14 Sep '07

All the really trendy network services these days broadcast their presence on the LAN using mDNS. In Linux world this means becoming an Avahi client and registering our services. virt-manager is also able to become an Avahi client and browser for services. So you'll be able to let the user just pick a host straight off a list instead of typing in hostname. The attached patch does two things: - Extends our event loop implementation so it can modify the event mask associated with an FD, and the timeout associated with a timer. While you could simulate this with an add & remove, this has the possibility of failure (from malloc). Merely updating an existing event can be done without failure. Avahi needs this ability for its event loop integration - Added qemu/mdns.c file to actually provide the service information. This has two parts. The first section of code is taken straight from one of the Avahi example programs. The second section is a implementaiton of the Avahi event loop contract in terms of our event API - it works very nicely which says good things about design of our event loop Some things... - I arbitrarily picked a service type of '_libvirtd._tcp'. The docs on picking service types seem non-existant on Avahi website, but it seems to be common to use service name from /etc/services and protocol both prefixed with _. - I advertise two subtypes, of '_xen.libvirtd._tcp' and '_qemu.libvirtd._tcp' What I actually want todo is to be able to probe the libvirt local drivers to auto-discover what virtualization platforms are available. A sort of lightweight virConnectOpen which merely returns TRUE/FALSE and doesn't actually allocate a virConnectPtr object. Need to extend the internal driver API for this. - I want to advertise whether the server is configured with TLS certs or not, so remote clients can automatically choose to use SSH urls with the remote driver if neccessary. - Let the admin turn advertisement on/off in the config file because some people may not like it on their LAN. If you fancy trying it, avahi-browse --all from another host on the LAN should show the service being advertised. The advertisements do not cross LAN routers by default. Dan. -- |=- Red Hat, Engineering, Emerging Technologies, Boston. +1 978 392 2496 -=| |=- Perl modules: http://search.cpan.org/~danberr/ -=| |=- Projects: http://freshmeat.net/~danielpb/ -=| |=- GnuPG: 7D3B9505 F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 -=|

4 8

[Libvir] Segfault with invalid virConnectPtr
by Richard W.M. Jones 13 Sep '07

13 Sep '07

Program terminated with signal 11, Segmentation fault. #0 0x0000003d8b472a1b in free () from /lib64/libc.so.6 (gdb) bt #0 0x0000003d8b472a1b in free () from /lib64/libc.so.6 #1 0x00002aaaaaae8dd7 in virResetError (err=0x33535c8) at virterror.c:111 #2 0x00002aaaaaae8fce in __virRaiseError (conn=0x33535a0, dom=0x0, net=0x0, domain=0, code=6, level=VIR_ERR_ERROR, str1=0x2aaaaab0c678 "invalid connection pointer in %s", str2=0x2aaaaab08560 "virConnectNumOfDomains", str3=0x0, int1=0, int2=0, msg=0x2aaaaab0c678 "invalid connection pointer in %s") at virterror.c:358 #3 0x00002aaaaaacfa8e in virLibConnError (conn=0x33535a0, error=VIR_ERR_INVALID_CONN, info=0x2aaaaab08560 "virConnectNumOfDomains") at libvirt.c:127 #4 0x00002aaaaaad1052 in virConnectNumOfDomains (conn=0x736e6961) at libvirt.c:758 #5 0x000000000043fa4e in ?? () A preliminary look at the code seems to indicate a fault in this logic: int virConnectNumOfDomains(virConnectPtr conn) { DEBUG("conn=%p", conn); if (!VIR_IS_CONNECT(conn)) { virLibConnError(conn, VIR_ERR_INVALID_CONN, __FUNCTION__); The VIR_IS_CONNECT macro is defined as: #define VIR_CONNECT_MAGIC 0x4F23DEAD #define VIR_IS_CONNECT(obj) ((obj) && (obj)->magic==VIR_CONNECT_MAGIC) Obviously if VIR_IS_CONNECT fails then "conn" should not be used further, so calling virLibConnError (conn, ...) is wrong. Personally I think when we detect memory corruption in a C program we should just call abort(). I'll see if I can come up with a patch to fix this later ... at the moment I'm more interested in why my program is passing an invalid connection pointer in the first place :-( Rich. -- Emerging Technologies, Red Hat - http://et.redhat.com/~rjones/ Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 03798903

2 4