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[libvirt] PATCH [0/3] Filesystem pool formatting
by David Allan 22 Feb '10

22 Feb '10

I finished these patches this afternoon, and I need to do a bit more testing before I'm comfortable having these patches committed, but I'm sending them along so I can get everybody's feedback overnight. In particular, I'm wondering if my move of the pool unref call is correct. Dave

5 11

[libvirt] Failures in existing qemu domain save/restore.
by Laine Stump 21 Feb '10

21 Feb '10

After running a bunch more tests, I am now noticing failures in domain save/restore *without* my patch (ie sources built straight from git), not 100% in either case (with or without patches), and the same saved domain sometimes fails to restore and sometimes is successful. (Most of the time (but not all), when I try to restore a domain immediately after a save, it fails, but if I then force shutdown of that failed restore and restore again from the same file, it succeeds. (Note that this is all to/from a local disk - it's not related to NFS) Is there a known problem in domain save/restore? Is anyone else seeing any failures? On 02/19/2010 02:30 AM, Laine Stump wrote: > (This patch requires that you first apply the virFileOperation patches > that I sent to the list yesterday.) > > I'm hoping someone else's keen eye can see what I'm failing to see > here. > > The patch following this message makes domain save "work" on > root-squash NFS (both the libvirt header and the QEMU state are saved > to the file), but the files that it saves don't restore properly, even > when simply saving to a local directory w/o forking - the guest screen > comes up black, or reboots immediately, or some other such thing. I've > looked at the data files and the code, and can't see what difference > is causing this - at least the header written by libvirt seems to be > the same, and the part written by qemu starts in the same place and > looks similar. > > If anyone's got an idea, please let me know! I'd like to get this > figured out and a working patch submitted before the day is done. > > -- > libvir-list mailing list > libvir-list(a)redhat.com > https://www.redhat.com/mailman/listinfo/libvir-list > >

1 0

[libvirt] [PATCH] docs: add 3 missing spaces
by Dan Kenigsberg 21 Feb '10

21 Feb '10

From: danken <danken(a)redhat.com> --- docs/architecture.html.in | 2 +- docs/auth.html.in | 2 +- docs/logging.html.in | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/docs/architecture.html.in b/docs/architecture.html.in index 8eb6458..f5cc520 100644 --- a/docs/architecture.html.in +++ b/docs/architecture.html.in @@ -83,7 +83,7 @@ drivers present in driver.h: <li>xen_internal: provide the implementation of the functions possible via direct hypervisor access</li> <li>proxy_internal: provide read-only Xen access via a proxy, the proxy code - is in the <code>proxy/</code>directory.</li> + is in the <code>proxy/</code> directory.</li> <li>xm_internal: provide support for Xen defined but not running domains.</li> <li>qemu_internal: implement the driver functions for QEmu and diff --git a/docs/auth.html.in b/docs/auth.html.in index 3ca40c3..ab6c3e9 100644 --- a/docs/auth.html.in +++ b/docs/auth.html.in @@ -72,7 +72,7 @@ available. The two libvirt daemon actions available are named <code>org.libvirt. for the RO socket, and <code>org.libvirt.unix.manage</code> for the RW socket. -As an example, to allow a user <code>fred</code>full access to the RW socket, +As an example, to allow a user <code>fred</code> full access to the RW socket, while requiring <code>joe</code> to authenticate with the admin password, would require adding the following snippet to <code>PolicyKit.conf</code>. diff --git a/docs/logging.html.in b/docs/logging.html.in index 63a0b05..f4a5878 100644 --- a/docs/logging.html.in +++ b/docs/logging.html.in @@ -96,7 +96,7 @@ <li><code>x:stderr</code> output goes to stderr</li> <li><code>x:syslog:name</code> use syslog for the output and use the given <code>name</code> as the ident</li> - <li><code>x:file:file_path</code>output to a file, with the given + <li><code>x:file:file_path</code> output to a file, with the given filepath</li> </ul> In all cases the x prefix is the minimal level, acting as a filter: -- 1.6.6

2 1

[libvirt] [RFC][PATCH 2/2] Automatically recreate macvtap interface and reconnect to qemu
by Ed Swierk 20 Feb '10

20 Feb '10

This patch implements a thread for each VM that iterates through the list of macvtap interfaces, attempting to recreate each one and reconnect it to qemu. See the PATCH 0 email for discussion. --- Index: libvirt-0.7.6/src/qemu/qemu_driver.c =================================================================== --- libvirt-0.7.6.orig/src/qemu/qemu_driver.c +++ libvirt-0.7.6/src/qemu/qemu_driver.c @@ -76,6 +76,7 @@ #include "xml.h" #include "cpu/cpu.h" #include "macvtap.h" +#include "threads.h" #define VIR_FROM_THIS VIR_FROM_QEMU @@ -96,6 +97,8 @@ struct _qemuDomainObjPrivate { int *vcpupids; qemuDomainPCIAddressSetPtr pciaddrs; + + pthread_t reconnectNetBackendsThread; }; static int qemudShutdown(void); @@ -143,6 +146,8 @@ static int qemudDomainDisconnectNetBacke virDomainObjPtr vm, virDomainNetDefPtr net); +static void *qemudDomainReconnectNetBackends(void *opaque); + static struct qemud_driver *qemu_driver = NULL; @@ -2794,6 +2799,10 @@ static int qemudStartVMDaemon(virConnect if (virDomainSaveStatus(conn, driver->caps, driver->stateDir, vm) < 0) goto abort; + if (pthread_create(&priv->reconnectNetBackendsThread, NULL, + qemudDomainReconnectNetBackends, vm->def->uuid)) + goto abort; + return 0; cleanup: @@ -5627,7 +5636,7 @@ static int qemudDomainConnectNetBackend( unsigned int qemuCmdFlags) { qemuDomainObjPrivatePtr priv = vm->privateData; - char *tapfd_name = NULL; + char *hostnet_name = NULL; int tapfd = -1; char *netstr = NULL; int ret = -1; @@ -5664,27 +5673,30 @@ static int qemudDomainConnectNetBackend( if (tapfd < 0) return -1; - if (virAsprintf(&tapfd_name, "fd-%s", net->info.alias) < 0) { + if (virAsprintf(&hostnet_name, "host%s", net->info.alias) < 0) { virReportOOMError(conn); close(tapfd); return -1; } if (!(netstr = qemuBuildHostNetStr(conn, net, ' ', - vlan, tapfd_name))) { - VIR_FREE(tapfd_name); + vlan, hostnet_name))) { + VIR_FREE(hostnet_name); close(tapfd); return -1; } qemuDomainObjEnterMonitorWithDriver(driver, vm); - if (qemuMonitorSendFileHandle(priv->mon, tapfd_name, tapfd) < 0) + if (qemuMonitorRemoveHostNetwork(priv->mon, vlan, hostnet_name) < 0) + VIR_INFO0("Did not remove existing host network"); + + if (qemuMonitorSendFileHandle(priv->mon, hostnet_name, tapfd) < 0) goto out; if (qemuMonitorAddHostNetwork(priv->mon, netstr) < 0) { - if (qemuMonitorCloseFileHandle(priv->mon, tapfd_name) < 0) - VIR_WARN(_("Failed to close tapfd with '%s'"), tapfd_name); + if (qemuMonitorCloseFileHandle(priv->mon, hostnet_name) < 0) + VIR_WARN(_("Failed to close tapfd with '%s'"), hostnet_name); goto out; } @@ -5693,7 +5705,7 @@ static int qemudDomainConnectNetBackend( out: qemuDomainObjExitMonitorWithDriver(driver, vm); VIR_FREE(netstr); - VIR_FREE(tapfd_name); + VIR_FREE(hostnet_name); close(tapfd); return ret; } @@ -8549,6 +8561,72 @@ out: return ret; } +static void *qemudDomainReconnectNetBackends(void *opaque) +{ + virConnectPtr conn = virConnectOpen("qemu:///system"); + struct qemud_driver *driver = conn->privateData; + const unsigned char *uuid = opaque; + + while (1) { + virDomainObjPtr vm; + unsigned int qemuCmdFlags; + int i; + + usleep(1000000); + + VIR_ERROR(_("qemuDomainReconnectNetBackends (%p %p)"), + conn, driver); + + qemuDriverLock(driver); + vm = virDomainFindByUUID(&driver->domains, uuid); + if (!vm) { + VIR_ERROR0("qemuDomainReconnectNetBackends done"); + qemuDriverUnlock(driver); + break; + } + + VIR_ERROR(_("qemuDomainReconnectNetBackends (%s)"), + vm->def->name); + + if (qemudExtractVersionInfo(vm->def->emulator, + NULL, + &qemuCmdFlags) < 0) + goto cleanup; + + if (qemuDomainObjBeginJobWithDriver(driver, vm) < 0) + goto cleanup; + + if (!virDomainObjIsActive(vm)) + goto endjob; + + for (i = 0 ; i < vm->def->nnets ; i++) { + virDomainNetDefPtr net = vm->def->nets[i]; + + VIR_ERROR(_("qemuDomainReconnectNetBackends (%s)"), net->ifname); + + if (net->type != VIR_DOMAIN_NET_TYPE_DIRECT) + continue; + + if (qemudDomainConnectNetBackend(conn, driver, vm, + net, qemuCmdFlags) < 0) + VIR_ERROR(_("qemudDomainConnectNetBackend failed (%s)"), + net->ifname); + } + + endjob: + if (vm && + qemuDomainObjEndJob(vm) == 0) + vm = NULL; + + cleanup: + if (vm) + virDomainObjUnlock(vm); + qemuDriverUnlock(driver); + } + + return NULL; +} + static int qemuCPUCompare(virConnectPtr conn, const char *xmlDesc,

1 0

[libvirt] [RFC][PATCH 1/2] Separate backend setup from NIC device add/remove
by Ed Swierk 20 Feb '10

20 Feb '10

This patch moves backend setup code from qemudDomainAttachNetDevice and qemudDomainDetachNetDevice into separate functions. While the intent is to allow the new functions to be called separately without affecting VM NIC devices, this is arguably a worthwhile refactoring on its own. Currently it's based on 0.7.6 with some macvtap patches. I can rebase it against git if there's interest. Signed-off-by: Ed Swierk <eswierk(a)aristanetworks.com> --- Move the code that creates and destroys the network backend and connects it to qemu from the code that creates the virtual NIC. Index: libvirt-0.7.6/src/qemu/qemu_driver.c =================================================================== --- libvirt-0.7.6.orig/src/qemu/qemu_driver.c +++ libvirt-0.7.6/src/qemu/qemu_driver.c @@ -132,6 +132,17 @@ static int qemuDetectVcpuPIDs(virConnect static int qemuUpdateActivePciHostdevs(struct qemud_driver *driver, virDomainDefPtr def); +static int qemudDomainConnectNetBackend(virConnectPtr conn, + struct qemud_driver *driver, + virDomainObjPtr vm, + virDomainNetDefPtr net, + unsigned int qemuCmdFlags); + +static int qemudDomainDisconnectNetBackend(virConnectPtr conn, + struct qemud_driver *driver, + virDomainObjPtr vm, + virDomainNetDefPtr net); + static struct qemud_driver *qemu_driver = NULL; @@ -5609,19 +5620,17 @@ error: } -static int qemudDomainAttachNetDevice(virConnectPtr conn, - struct qemud_driver *driver, - virDomainObjPtr vm, - virDomainNetDefPtr net, - unsigned int qemuCmdFlags) +static int qemudDomainConnectNetBackend(virConnectPtr conn, + struct qemud_driver *driver, + virDomainObjPtr vm, + virDomainNetDefPtr net, + unsigned int qemuCmdFlags) { qemuDomainObjPrivatePtr priv = vm->privateData; char *tapfd_name = NULL; int tapfd = -1; - char *nicstr = NULL; char *netstr = NULL; int ret = -1; - virDomainDevicePCIAddress guestAddr; int vlan; if (!(qemuCmdFlags & QEMUD_CMD_FLAG_HOST_NET_ADD)) { @@ -5630,142 +5639,132 @@ static int qemudDomainAttachNetDevice(vi return -1; } + if (priv->monConfig->type != VIR_DOMAIN_CHR_TYPE_UNIX) { + qemudReportError(conn, dom, NULL, VIR_ERR_NO_SUPPORT, + _("network device type '%s' cannot be attached: " + "qemu is not using a unix socket monitor"), + virDomainNetTypeToString(net->type)); + return -1; + } + + if ((vlan = qemuDomainNetVLAN(net)) < 0) { + qemudReportError(conn, NULL, NULL, VIR_ERR_NO_SUPPORT, "%s", + _("Unable to connect network backend without vlan")); + goto out; + } + if (net->type == VIR_DOMAIN_NET_TYPE_BRIDGE || net->type == VIR_DOMAIN_NET_TYPE_NETWORK) { - if (priv->monConfig->type != VIR_DOMAIN_CHR_TYPE_UNIX) { - qemudReportError(conn, dom, NULL, VIR_ERR_NO_SUPPORT, - _("network device type '%s' cannot be attached: " - "qemu is not using a unix socket monitor"), - virDomainNetTypeToString(net->type)); - return -1; - } - - if ((tapfd = qemudNetworkIfaceConnect(conn, driver, net, qemuCmdFlags)) < 0) - return -1; + tapfd = qemudNetworkIfaceConnect(conn, driver, net, qemuCmdFlags); } else if (net->type == VIR_DOMAIN_NET_TYPE_DIRECT) { - if (priv->monConfig->type != VIR_DOMAIN_CHR_TYPE_UNIX) { - qemudReportError(conn, dom, NULL, VIR_ERR_NO_SUPPORT, - _("direct device type '%s' cannot be attached: " - "qemu is not using a unix socket monitor"), - virDomainNetTypeToString(net->type)); - return -1; - } + tapfd = qemudPhysIfaceConnect(conn, net, + net->data.direct.linkdev, + net->data.direct.mode); + } + if (tapfd < 0) + return -1; - if ((tapfd = qemudPhysIfaceConnect(conn, net, - net->data.direct.linkdev, - net->data.direct.mode)) < 0) - return -1; + if (virAsprintf(&tapfd_name, "fd-%s", net->info.alias) < 0) { + virReportOOMError(conn); + close(tapfd); + return -1; } - if (VIR_REALLOC_N(vm->def->nets, vm->def->nnets+1) < 0) - goto no_memory; + if (!(netstr = qemuBuildHostNetStr(conn, net, ' ', + vlan, tapfd_name))) { + VIR_FREE(tapfd_name); + close(tapfd); + return -1; + } + + qemuDomainObjEnterMonitorWithDriver(driver, vm); + + if (qemuMonitorSendFileHandle(priv->mon, tapfd_name, tapfd) < 0) + goto out; + + if (qemuMonitorAddHostNetwork(priv->mon, netstr) < 0) { + if (qemuMonitorCloseFileHandle(priv->mon, tapfd_name) < 0) + VIR_WARN(_("Failed to close tapfd with '%s'"), tapfd_name); + goto out; + } + + ret = 0; + +out: + qemuDomainObjExitMonitorWithDriver(driver, vm); + VIR_FREE(netstr); + VIR_FREE(tapfd_name); + close(tapfd); + return ret; +} + +static int qemudDomainAttachNetDevice(virConnectPtr conn, + struct qemud_driver *driver, + virDomainObjPtr vm, + virDomainNetDefPtr net, + unsigned int qemuCmdFlags) +{ + qemuDomainObjPrivatePtr priv = vm->privateData; + char *nicstr = NULL; + int ret = -1; + virDomainDevicePCIAddress guestAddr; + int vlan; + + if (VIR_REALLOC_N(vm->def->nets, vm->def->nnets+1) < 0) { + virReportOOMError(conn); + return -1; + } if ((qemuCmdFlags & QEMUD_CMD_FLAG_NET_NAME) || (qemuCmdFlags & QEMUD_CMD_FLAG_DEVICE)) { if (qemuAssignDeviceNetAlias(vm->def, net, -1) < 0) - goto cleanup; + goto out; } if ((qemuCmdFlags & QEMUD_CMD_FLAG_DEVICE) && qemuDomainPCIAddressEnsureAddr(priv->pciaddrs, &net->info) < 0) - goto cleanup; - - vlan = qemuDomainNetVLAN(net); + goto out; - if (vlan < 0) { + if ((vlan = qemuDomainNetVLAN(net)) < 0) { qemudReportError(conn, NULL, NULL, VIR_ERR_NO_SUPPORT, "%s", _("Unable to attach network devices without vlan")); - goto cleanup; - } - - if (tapfd != -1) { - if (virAsprintf(&tapfd_name, "fd-%s", net->info.alias) < 0) - goto no_memory; - - qemuDomainObjEnterMonitorWithDriver(driver, vm); - if (qemuMonitorSendFileHandle(priv->mon, tapfd_name, tapfd) < 0) { - qemuDomainObjExitMonitorWithDriver(driver, vm); - goto cleanup; - } - qemuDomainObjExitMonitorWithDriver(driver, vm); + goto out; } - if (!(netstr = qemuBuildHostNetStr(conn, net, ' ', - vlan, tapfd_name))) - goto try_tapfd_close; - - qemuDomainObjEnterMonitorWithDriver(driver, vm); - if (qemuMonitorAddHostNetwork(priv->mon, netstr) < 0) { - qemuDomainObjExitMonitorWithDriver(driver, vm); - goto try_tapfd_close; + if (qemudDomainConnectNetBackend(conn, driver, vm, net, qemuCmdFlags) < 0) { + VIR_WARN0(_("Failed to connect network backend")); + goto out; } - qemuDomainObjExitMonitorWithDriver(driver, vm); - - if (tapfd != -1) - close(tapfd); - tapfd = -1; if (!(nicstr = qemuBuildNicStr(conn, net, NULL, vlan))) - goto try_remove; + goto out_remove; qemuDomainObjEnterMonitorWithDriver(driver, vm); if (qemuMonitorAddPCINetwork(priv->mon, nicstr, &guestAddr) < 0) { qemuDomainObjExitMonitorWithDriver(driver, vm); - goto try_remove; + goto out_remove; } net->info.type = VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI; memcpy(&net->info.addr.pci, &guestAddr, sizeof(guestAddr)); qemuDomainObjExitMonitorWithDriver(driver, vm); + vm->def->nets[vm->def->nnets++] = net; ret = 0; + goto out; - vm->def->nets[vm->def->nnets++] = net; +out_remove: + if (qemudDomainDisconnectNetBackend(conn, driver, vm, net) < 0) + VIR_WARN0("Unable to disconnect network backend"); -cleanup: +out: if ((ret != 0) && (qemuCmdFlags & QEMUD_CMD_FLAG_DEVICE) && (net->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI) && qemuDomainPCIAddressReleaseAddr(priv->pciaddrs, &net->info) < 0) VIR_WARN0("Unable to release PCI address on NIC"); - VIR_FREE(nicstr); - VIR_FREE(netstr); - VIR_FREE(tapfd_name); - if (tapfd != -1) - close(tapfd); - return ret; - -try_remove: - if (vlan < 0) { - VIR_WARN0(_("Unable to remove network backend")); - } else { - char *hostnet_name; - if (virAsprintf(&hostnet_name, "host%s", net->info.alias) < 0) - goto no_memory; - qemuDomainObjEnterMonitorWithDriver(driver, vm); - if (qemuMonitorRemoveHostNetwork(priv->mon, vlan, hostnet_name) < 0) - VIR_WARN(_("Failed to remove network backend for vlan %d, net %s"), - vlan, hostnet_name); - qemuDomainObjExitMonitorWithDriver(driver, vm); - VIR_FREE(hostnet_name); - } - goto cleanup; - -try_tapfd_close: - if (tapfd_name) { - qemuDomainObjEnterMonitorWithDriver(driver, vm); - if (qemuMonitorCloseFileHandle(priv->mon, tapfd_name) < 0) - VIR_WARN(_("Failed to close tapfd with '%s'"), tapfd_name); - qemuDomainObjExitMonitorWithDriver(driver, vm); - } - - goto cleanup; - -no_memory: - virReportOOMError(conn); - goto cleanup; } @@ -6207,82 +6206,95 @@ cleanup: return ret; } -static int -qemudDomainDetachNetDevice(virConnectPtr conn, - struct qemud_driver *driver, - virDomainObjPtr vm, - virDomainDeviceDefPtr dev) +static int qemudDomainDisconnectNetBackend(virConnectPtr conn, + struct qemud_driver *driver, + virDomainObjPtr vm, + virDomainNetDefPtr net) { - int i, ret = -1; - virDomainNetDefPtr detach = NULL; qemuDomainObjPrivatePtr priv = vm->privateData; int vlan; char *hostnet_name = NULL; + if ((vlan = qemuDomainNetVLAN(net)) < 0) { + qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, + "%s", _("unable to determine original VLAN")); + return -1; + } + + if (virAsprintf(&hostnet_name, "host%s", net->info.alias) < 0) { + virReportOOMError(NULL); + return -1; + } + + qemuDomainObjEnterMonitorWithDriver(driver, vm); + if (qemuMonitorRemoveHostNetwork(priv->mon, vlan, hostnet_name) < 0) + VIR_WARN0("Failed to remove host network"); + qemuDomainObjExitMonitorWithDriver(driver, vm); + +#if WITH_MACVTAP + if (net->type == VIR_DOMAIN_NET_TYPE_DIRECT) { + if (net->ifname) + delMacvtap(conn, net->ifname); + } +#endif + + VIR_FREE(hostnet_name); + return 0; +} + +static int qemudDomainDetachNetDevice(virConnectPtr conn, + struct qemud_driver *driver, + virDomainObjPtr vm, + virDomainDeviceDefPtr dev) +{ + int i = -1; + virDomainNetDefPtr net = NULL; + qemuDomainObjPrivatePtr priv = vm->privateData; + for (i = 0 ; i < vm->def->nnets ; i++) { - virDomainNetDefPtr net = vm->def->nets[i]; + virDomainNetDefPtr n = vm->def->nets[i]; - if (!memcmp(net->mac, dev->data.net->mac, sizeof(net->mac))) { - detach = net; + if (!memcmp(n->mac, dev->data.net->mac, sizeof(n->mac))) { + net = n; break; } } - if (!detach) { + if (!net) { qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, _("network device %02x:%02x:%02x:%02x:%02x:%02x not found"), dev->data.net->mac[0], dev->data.net->mac[1], dev->data.net->mac[2], dev->data.net->mac[3], dev->data.net->mac[4], dev->data.net->mac[5]); - goto cleanup; + return -1; } - if (!virDomainDeviceAddressIsValid(&detach->info, + if (!virDomainDeviceAddressIsValid(&net->info, VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI)) { qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, "%s", _("device cannot be detached without a PCI address")); - goto cleanup; - } - - if ((vlan = qemuDomainNetVLAN(detach)) < 0) { - qemudReportError(conn, NULL, NULL, VIR_ERR_OPERATION_FAILED, - "%s", _("unable to determine original VLAN")); - goto cleanup; - } - - if (virAsprintf(&hostnet_name, "host%s", detach->info.alias) < 0) { - virReportOOMError(NULL); - goto cleanup; + return -1; } qemuDomainObjEnterMonitorWithDriver(driver, vm); if (qemuMonitorRemovePCIDevice(priv->mon, - &detach->info.addr.pci) < 0) { - qemuDomainObjExitMonitorWithDriver(driver, vm); - goto cleanup; - } - - if (qemuMonitorRemoveHostNetwork(priv->mon, vlan, hostnet_name) < 0) { + &net->info.addr.pci) < 0) { qemuDomainObjExitMonitorWithDriver(driver, vm); - goto cleanup; + return -1; } qemuDomainObjExitMonitorWithDriver(driver, vm); -#if WITH_MACVTAP - if (detach->type == VIR_DOMAIN_NET_TYPE_DIRECT) { - if (detach->ifname) - delMacvtap(conn, detach->ifname); - } -#endif + if (qemudDomainDisconnectNetBackend(conn, driver, vm, net) < 0) + VIR_WARN0("Failed to disconnect network backend"); - if ((driver->macFilter) && (detach->ifname != NULL)) { + if ((driver->macFilter) && (net->ifname != NULL)) { if ((errno = networkDisallowMacOnPort(conn, driver, - detach->ifname, - detach->mac))) { + net->ifname, + net->mac))) { virReportSystemError(conn, errno, _("failed to remove ebtables rule on '%s'"), - detach->ifname); + net->ifname); } } @@ -6299,13 +6311,9 @@ qemudDomainDetachNetDevice(virConnectPtr VIR_FREE(vm->def->nets); vm->def->nnets = 0; } - virDomainNetDefFree(detach); + virDomainNetDefFree(net); - ret = 0; - -cleanup: - VIR_FREE(hostnet_name); - return ret; + return 0; } static int qemudDomainDetachHostPciDevice(virConnectPtr conn,

1 0

[libvirt] [RFC][PATCH 0/2] Dynamic backend setup for macvtap interfaces
by Ed Swierk 20 Feb '10

20 Feb '10

Using a bridge to connect a qemu NIC to a host interface offers a fair amount of flexibility to reconfigure the host without restarting the VM. For example, if the bridge connects host interface eth0 to the qemu tap0 interface, eth0 can be hot-removed and hot-plugged without affecting the VM. Similarly, if the bridge connects host VLAN interface vlan0 to the qemu tap0 interface, the admin can easily replace vlan0 with vlan1 without the VM noticing. Using the macvtap driver instead of a kernel bridge, the host interface is much more tightly tied to the VM. Qemu communicates with the macvtap interface through a file descriptor, and the macvtap interface is bound permanently to a specific host interface when it is first created. What's more, if the underlying host interface disappears, the macvtap interface vanishes along with it, leaving the VM holding a file descriptor for a deleted file. To avoid race conditions during system startup, I would like libvirt to allow starting up the VM with a NIC even if the underlying host interface doesn't yet exist, deferring creation of the macvtap interface (analogous to starting up the VM with a tap interface bound to an orphan bridge). To support adding and removing a host interface without restarting the VM, I would like libvirt to react to the (re)appearance of the underlying host interface, creating a new macvtap interface and passing the new fd to qemu to reconnect to the NIC. (It would also be nice if libvirt allowed the user to change which underlying host interface the qemu NIC is connected to. I'm ignoring this issue for now, except to note that implementing the above features should make this easier.) The libvirt API already supports domainAttachDevice and domainDetachDevice to add or remove an interface while the VM is running. In the qemu implementation, these commands add or remove the VM NIC device as well as reconfiguring the host side. This works only if the OS and application running in the VM can handle PCI hotplug and dynamically reconfigure its network. I would like to isolate the VM from changes to the host network setup, whether you use macvtap or a bridge. The changes I think are needed to implement this include: 1. Refactor qemudDomainAttachNetDevice/qemudDomainDetachNetDevice, which currently handle both backend (host) setup and adding/removing the VM NIC device; move the backend setup code into separate functions that can called separately without affecting VM devices. 2. Implement a thread or task that watches for changes to the underlying host interface for each configured macvtap interface, and reacts by invoking the appropriate backend setup code. 3. Change qemudBuildCommandLine to defer backend setup if qemu supports the necessary features for doing it later (e.g. the host_net_add monitor command). 4. Implement appropriate error handling and reporting, and any necessary changes to the configuration schema. The following patches are a partial implementation of the above as a proof of concept. Patch 1 implements change (1) above, moving the backend setup code to new functions qemudDomainConnectNetBackend/qemudDomainDisconnectNetBackend, and calling these functions from the existing qemudDomainAttachNetDevice/qemudDomainDetachNetDevice. I think this change is useful on its own: it breaks up two monster functions into more manageable pieces, and eliminates some code duplication (e.g. the try_remove clause at the end of qemudDomainAttachNetDevice). Patch 2 is a godawful hack roughly implementing change (2) above (did I mention that this is a proof of concept?). It spawns a thread that simply tries reconnecting the backend of each macvtap interface once a second. As long as the interface is already up, the reconnection fails. If the macvtap interface goes away because the underlying host interface disappears, the reconnection fails until the host interface reappears. I ran into two major issues while implementing change (2): - Can we use the existing virEvent functions to invoke the reconnection process, triggered either by a timer or by an event from the host? It seems like this ought to work, but it appears that communication between libvirt and the qemu monitor relies on an event, and since all events run in the same thread, there's no way for an event to call the monitor. - Should the reconnection process use udev or hal to get notifications, or leverage the node device code which itself uses udev or hal? Currently there doesn't appear to be a way to get notifications of changes to node devices; if there were, we'd still need to address the threading issue. If we use node devices, what changes to the configuration schema would be needed to associate a macvtap interface with the underlying node device? I didn't attempt to implement changes (3) or (4) above but would welcome input on those items as well. --Ed

1 0

[libvirt] [PATCH 0/1] A couple of problems with the daemon-conf test
by David Allan 19 Feb '10

19 Feb '10

Here's a patch fixing two problems I found with the daemon-conf test that prevented the test from passing if the system libvirt was running on my system. The first change only affects the direct running of the daemon-conf script, i.e, if someone executes ./daemon-conf, which will always exit failure because the default config file contains a line that the test believes should not be there. The invocation by make-check supplies a different config file that's not subject to that problem. The second problem is that the corrupt config tests don't supply the pid-file argument to libvirt, so on my system it was attempting to use the same pidfile as the running system daemon and failing all the tests except the valid config test. Supplying the --pid-file argument when running the corrupt config tests as it is supplied for the valid config tests fixes the problem. Dave

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[libvirt] [PATCH] virFork: placate static analyzers: ignore pthread_sigmask return value
by Jim Meyering 19 Feb '10

19 Feb '10

Since we check all other uses of pthread_sigmask, be consistent and clear: mark that we're deliberately ignoring this one. >From 0cb4b2ffa51bb8c73243876221bff6d7edecd9cf Mon Sep 17 00:00:00 2001 From: Jim Meyering <meyering(a)redhat.com> Date: Fri, 19 Feb 2010 18:40:14 +0100 Subject: [PATCH] virFork: placate static analyzers: ignore pthread_sigmask return value * src/util/util.c: Include "ignore-value.h". (virFork): We really do want to ignore pthread_sigmask failure. --- src/util/util.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/src/util/util.c b/src/util/util.c index 624e570..cf7bba5 100644 --- a/src/util/util.c +++ b/src/util/util.c @@ -69,6 +69,7 @@ #include "virterror_internal.h" #include "logging.h" #include "event.h" +#include "ignore-value.h" #include "buf.h" #include "util.h" #include "memory.h" @@ -344,7 +345,7 @@ int virFork(pid_t *pid) { if (*pid < 0) { /* attempt to restore signal mask, but ignore failure, to avoid obscuring the fork failure */ - pthread_sigmask(SIG_SETMASK, &oldmask, NULL); + ignore_value (pthread_sigmask(SIG_SETMASK, &oldmask, NULL)); virReportSystemError(saved_errno, "%s", _("cannot fork child process")); goto cleanup; -- 1.7.0.233.g05e1a

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[libvirt] [PATCH] virBufferVSprintf: do not omit va_end(argptr) call
by Jim Meyering 19 Feb '10

19 Feb '10

Just realized I didn't post a version of this without the gnulib diff that Eric pointed out, so here you go: >From 4501145dd3529dc510e6cb52025a71dd0b111b4d Mon Sep 17 00:00:00 2001 From: Jim Meyering <meyering(a)redhat.com> Date: Thu, 18 Feb 2010 21:25:01 +0100 Subject: [PATCH] virBufferVSprintf: do not omit va_end(argptr) call * src/util/buf.c (virBufferVSprintf): Do not omit va_end(argptr). Improved-by: Daniel Veillard. --- src/util/buf.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/src/util/buf.c b/src/util/buf.c index cc0a087..fc1217b 100644 --- a/src/util/buf.c +++ b/src/util/buf.c @@ -245,12 +245,15 @@ virBufferVSprintf(const virBufferPtr buf, const char *format, ...) va_end(locarg); grow_size = (count > 1000) ? count : 1000; - if (virBufferGrow(buf, grow_size) < 0) + if (virBufferGrow(buf, grow_size) < 0) { + va_end(argptr); return; + } size = buf->size - buf->use - 1; va_copy(locarg, argptr); } + va_end(argptr); va_end(locarg); buf->use += count; buf->content[buf->use] = '\0'; -- 1.7.0.233.g05e1a

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[libvirt] [PATCH] xend_internal.c: don't dereference NULL for unexpected input
by Jim Meyering 19 Feb '10

19 Feb '10

My recent xend_internal.c change introduced a bug. "val" could be NULL just before the STREQ comparisons. Here's a fix: >From 5cc834ab30a444cc35ddc9317379f4be3b5cf4c5 Mon Sep 17 00:00:00 2001 From: Jim Meyering <meyering(a)redhat.com> Date: Fri, 19 Feb 2010 17:45:41 +0100 Subject: [PATCH] xend_internal.c: don't dereference NULL for unexpected input * src/xen/xend_internal.c (xenDaemonDomainSetAutostart): Avoid a NULL dereference upon non-SEXPR_VALUE'd on_xend_start. This bug was introduced by commit 37ce5600c0bb1aed9e2f2888922388de4340ebd3. --- src/xen/xend_internal.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/src/xen/xend_internal.c b/src/xen/xend_internal.c index 1f8b106..9d95291 100644 --- a/src/xen/xend_internal.c +++ b/src/xen/xend_internal.c @@ -4411,7 +4411,7 @@ xenDaemonDomainSetAutostart(virDomainPtr domain, if (autonode) { const char *val = (autonode->u.s.car->kind == SEXPR_VALUE ? autonode->u.s.car->u.value : NULL); - if (!STREQ(val, "ignore") && !STREQ(val, "start")) { + if (!val || (!STREQ(val, "ignore") && !STREQ(val, "start"))) { virXendError(domain->conn, VIR_ERR_INTERNAL_ERROR, "%s", _("unexpected value from on_xend_start")); goto error; -- 1.7.0.233.g05e1a

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