September 2011 - Devel - libvirt List Archives

[libvirt] [PATCH] virsh: avoid memory leak on cmdVolCreateAs
by ajia＠redhat.com 02 Sep '11

02 Sep '11

* tools/virsh.c: fix memory leak on cmdVolCreateAs function. * Detected in valgrind run: ==4746== ==4746== 48 (40 direct, 8 indirect) bytes in 1 blocks are definitely lost in loss record 26 of 52 ==4746== at 0x4A04A28: calloc (vg_replace_malloc.c:467) ==4746== by 0x4C76E51: virAlloc (memory.c:101) ==4746== by 0x4CD9418: virGetStoragePool (datatypes.c:592) ==4746== by 0x4D21367: remoteStoragePoolLookupByName (remote_driver.c:4126) ==4746== by 0x4CE42B0: virStoragePoolLookupByName (libvirt.c:10232) ==4746== by 0x40C276: vshCommandOptPoolBy (virsh.c:13660) ==4746== by 0x40CA37: cmdVolCreateAs (virsh.c:8094) ==4746== by 0x412AF2: vshCommandRun (virsh.c:13770) ==4746== by 0x422F11: main (virsh.c:15127) ==4746== ==4746== 1,011 bytes in 1 blocks are definitely lost in loss record 45 of 52 ==4746== at 0x4A05FDE: malloc (vg_replace_malloc.c:236) ==4746== by 0x4A06167: realloc (vg_replace_malloc.c:525) ==4746== by 0x4C76ECB: virReallocN (memory.c:161) ==4746== by 0x4C60319: virBufferGrow (buf.c:72) ==4746== by 0x4C606AA: virBufferAdd (buf.c:106) ==4746== by 0x40CB37: cmdVolCreateAs (virsh.c:8118) ==4746== by 0x412AF2: vshCommandRun (virsh.c:13770) ==4746== by 0x422F11: main (virsh.c:15127) ==4746== ==4746== LEAK SUMMARY: ==4746== definitely lost: 1,051 bytes in 2 blocks ==4746== indirectly lost: 8 bytes in 1 blocks ==4746== possibly lost: 0 bytes in 0 blocks ==4746== still reachable: 390,767 bytes in 1,373 blocks ==4746== suppressed: 0 bytes in 0 blocks * How to reproduce? % valgrind -v --leak-check=full virsh vol-create-as default foo.img 10M \ --allocation 0 --format qcow2 --backing-vol bar.img Notes: bar.img doesn't exist. Signed-off-by: Alex Jia <ajia(a)redhat.com> --- tools/virsh.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/tools/virsh.c b/tools/virsh.c index f9bcd2c..44c2f1c 100644 --- a/tools/virsh.c +++ b/tools/virsh.c @@ -8166,7 +8166,7 @@ cmdVolCreateAs(vshControl *ctl, const vshCmd *cmd) } if (snapVol == NULL) { vshError(ctl, _("failed to get vol '%s'"), snapshotStrVol); - return false; + goto cleanup; } char *snapshotStrVolPath; -- 1.7.1

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[libvirt] [PATCH] lxc: do not require 'ifconfig' or 'ipconfig' in container
by Scott Moser 02 Sep '11

02 Sep '11

Currently, the lxc implementation invokes 'ip' and 'ifconfig' commands inside a container using 'virRun'. That has the side effect of requiring those commands to be present and to function in a manner consistent with the usage. Some small roots (such as ttylinux) may not have 'ip' or 'ifconfig'. This patch replaces the use of these commands with usage of netdevice. The result is that lxc containers do not have to implement those commands, and lxc in libvirt is only dependent on the netdevice interface. I've tested this patch locally against the ubuntu libvirt version enough to verify its generally sane. I attempted to build upstream today, but failed with: /usr/bin/ld: ../src/.libs/libvirt_driver_qemu.a(libvirt_driver_qemu_la-qemu_domain.o): undefined reference to symbol 'xmlXPathRegisterNs@@LIBXML2_2.4.30 Thats probably a local issue only, but I wanted to get this patch up and see what others thought of it. This is ubuntu bug https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/828211 . diff --git a/src/lxc/veth.c b/src/lxc/veth.c index 34cb804..c24df91 100644 --- a/src/lxc/veth.c +++ b/src/lxc/veth.c @@ -12,8 +12,11 @@ #include <config.h> +#include <linux/sockios.h> +#include <net/if.h> #include <string.h> #include <stdio.h> +#include <sys/ioctl.h> #include <sys/types.h> #include <sys/wait.h> @@ -186,41 +189,49 @@ int vethDelete(const char *veth) * @veth: name of veth device * @upOrDown: 0 => down, 1 => up * - * Enables a veth device using the ifconfig command. A NULL inetAddress - * will cause it to be left off the command line. + * Enables a veth device using SIOCSIFFLAGS * - * Returns 0 on success or -1 in case of error + * Returns 0 on success, -1 on failure, with errno set */ int vethInterfaceUpOrDown(const char* veth, int upOrDown) { - int rc; - const char *argv[] = {"ifconfig", veth, NULL, NULL}; - int cmdResult = 0; + struct ifreq ifr; + int fd, ret; - if (0 == upOrDown) - argv[2] = "down"; - else - argv[2] = "up"; + if ((fd = socket(PF_PACKET, SOCK_DGRAM, 0)) == -1) + return(-1); - rc = virRun(argv, &cmdResult); + memset(&ifr, 0, sizeof(struct ifreq)); - if (rc != 0 || - (WIFEXITED(cmdResult) && WEXITSTATUS(cmdResult) != 0)) { - if (0 == upOrDown) + if (virStrcpyStatic(ifr.ifr_name, veth) == NULL) { + errno = EINVAL; + return -1; + } + + if ((ret = ioctl(fd, SIOCGIFFLAGS, &ifr)) == 0) { + if (upOrDown) + ifr.ifr_flags |= IFF_UP; + else + ifr.ifr_flags &= ~(IFF_UP | IFF_RUNNING); + + ret = ioctl(fd, SIOCSIFFLAGS, &ifr); + } + + close(fd); + if (ret == -1) + if (upOrDown == 0) /* * Prevent overwriting an error log which may be set * where an actual failure occurs. */ - VIR_DEBUG("Failed to disable '%s' (%d)", - veth, WEXITSTATUS(cmdResult)); + VIR_DEBUG("Failed to disable '%s'", veth); else vethError(VIR_ERR_INTERNAL_ERROR, - _("Failed to enable '%s' (%d)"), - veth, WEXITSTATUS(cmdResult)); - rc = -1; - } + _("Failed to enable '%s'"), veth); + else + ret = 0; - return rc; + return(ret); } /** @@ -279,17 +290,29 @@ int setMacAddr(const char* iface, const char* macaddr) * @iface: name of device * @new: new name of @iface * - * Changes the name of the given device with the - * given new name using this command: - * ip link set @iface name @new + * Changes the name of the given device. * - * Returns 0 on success or -1 in case of error + * Returns 0 on success, -1 on failure with errno set. */ int setInterfaceName(const char* iface, const char* new) { - const char *argv[] = { - "ip", "link", "set", iface, "name", new, NULL - }; + struct ifreq ifr; + int fd = socket(PF_PACKET, SOCK_DGRAM, 0); - return virRun(argv, NULL); + memset(&ifr, 0, sizeof(struct ifreq)); + + if (virStrcpyStatic(ifr.ifr_name, iface) == NULL) { + errno = EINVAL; + return -1; + } + + if (virStrcpyStatic(ifr.ifr_newname, new) == NULL) { + errno = EINVAL; + return -1; + } + + if (ioctl(fd, SIOCSIFNAME, &ifr)) + return -1; + + return 0; }

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[libvirt] [RFC] Create ptmx as a device
by Serge Hallyn 02 Sep '11

02 Sep '11

Hi, I'm seeing an issue with udev and libvirt-lxc. Libvirt-lxc creates /dev/ptmx as a symlink to /dev/pts/ptmx. When udev starts up, it checks the device type, sees ptmx is 'not right', and replaces it with a 'proper' ptmx. In lxc, /dev/ptmx is bind-mounted from /dev/pts/ptmx instead of being symlinked, so udev sees the right device type and leaves it alone. A patch like the following seems to work for me. Would there be any objections to this? >From 4c5035de52de7e06a0de9c5d0bab8c87a806cba7 Mon Sep 17 00:00:00 2001 From: Ubuntu <ubuntu(a)domU-12-31-39-14-F0-B3.compute-1.internal> Date: Wed, 31 Aug 2011 18:15:54 +0000 Subject: [PATCH 1/1] make ptmx a bind mount rather than symlink udev on some systems checks the device type of /dev/ptmx, and replaces it if not as expected. The symlink created by libvirt-lxc therefore gets replaced. By creating it as a bind mount, the device type is correct and udev leaves it alone. Signed-off-by: Serge Hallyn <serge.hallyn(a)canonical.com> --- src/lxc/lxc_container.c | 20 ++++++++++---------- 1 files changed, 10 insertions(+), 10 deletions(-) diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c index e425328..6991aec 100644 --- a/src/lxc/lxc_container.c +++ b/src/lxc/lxc_container.c @@ -543,18 +543,18 @@ static int lxcContainerPopulateDevices(void) } } + dev_t dev = makedev(LXC_DEV_MAJ_TTY, LXC_DEV_MIN_PTMX); + if (mknod("/dev/ptmx", S_IFCHR, dev) < 0 || + chmod("/dev/ptmx", 0666)) { + virReportSystemError(errno, "%s", + _("Failed to make device /dev/ptmx")); + return -1; + } + if (access("/dev/pts/ptmx", W_OK) == 0) { - if (symlink("/dev/pts/ptmx", "/dev/ptmx") < 0) { - virReportSystemError(errno, "%s", - _("Failed to create symlink /dev/ptmx to /dev/pts/ptmx")); - return -1; - } - } else { - dev_t dev = makedev(LXC_DEV_MAJ_TTY, LXC_DEV_MIN_PTMX); - if (mknod("/dev/ptmx", S_IFCHR, dev) < 0 || - chmod("/dev/ptmx", 0666)) { + if (mount("/dev/pts/ptmx", "/dev/ptmx", "ptmx", MS_BIND, NULL) < 0) { virReportSystemError(errno, "%s", - _("Failed to make device /dev/ptmx")); + _("Failed to bind-mount /dev/ptmx to /dev/pts/ptmx")); return -1; } } -- 1.7.5.4

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[libvirt] [PATCH 1/2] BlockJob: Bandwidth parameter is in MB when using text monitor
by Adam Litke 02 Sep '11

02 Sep '11

Due to an unfortunate precedent in qemu, the units for the bandwidth parameter to block_job_set_speed are different between the text monitor and the qmp monitor. While the qmp monitor uses bytes/s, the text monitor expects MB/s. Correct the units for the text interface. Signed-off-by: Adam Litke <agl(a)us.ibm.com> --- src/qemu/qemu_monitor_text.c | 3 +-- 1 files changed, 1 insertions(+), 2 deletions(-) diff --git a/src/qemu/qemu_monitor_text.c b/src/qemu/qemu_monitor_text.c index f37c98c..854ee7f 100644 --- a/src/qemu/qemu_monitor_text.c +++ b/src/qemu/qemu_monitor_text.c @@ -3067,8 +3067,7 @@ int qemuMonitorTextBlockJob(qemuMonitorPtr mon, ret = virAsprintf(&cmd, "%s", cmd_name); } else if (mode == BLOCK_JOB_SPEED) { cmd_name = "block_job_set_speed"; - ret = virAsprintf(&cmd, "%s %s %llu", cmd_name, device, - bandwidth * 1024ULL * 1024ULL); + ret = virAsprintf(&cmd, "%s %s %luM", cmd_name, device, bandwidth); } else if (mode == BLOCK_JOB_PULL) { cmd_name = "block_stream"; ret = virAsprintf(&cmd, "%s %s", cmd_name, device); -- 1.7.3

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[libvirt] [PATCH] BlockPull: Set initial bandwidth limit if specified
by Adam Litke 02 Sep '11

02 Sep '11

The libvirt BlockPull API supports the use of an initial bandwidth limit but the qemu block_stream API does not. To get the desired behavior we use the two APIs strung together: first BlockPull, then BlockJobSetSpeed. We can do this at the driver level to avoid duplicated code in each monitor path. Signed-off-by: Adam Litke <agl(a)us.ibm.com> --- src/qemu/qemu_driver.c | 8 +++++++- src/qemu/qemu_monitor_json.c | 4 ---- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 4e8c691..7476bb4 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -9418,8 +9418,14 @@ static int qemuDomainBlockPull(virDomainPtr dom, const char *path, unsigned long bandwidth, unsigned int flags) { + int ret; + virCheckFlags(0, -1); - return qemuDomainBlockJobImpl(dom, path, bandwidth, NULL, BLOCK_JOB_PULL); + ret = qemuDomainBlockJobImpl(dom, path, bandwidth, NULL, BLOCK_JOB_PULL); + if (ret == 0 && bandwidth != 0) + ret = qemuDomainBlockJobImpl(dom, path, bandwidth, NULL, + BLOCK_JOB_SPEED); + return ret; } static virDriver qemuDriver = { diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c index 715b26e..4ceb536 100644 --- a/src/qemu/qemu_monitor_json.c +++ b/src/qemu/qemu_monitor_json.c @@ -2956,10 +2956,6 @@ int qemuMonitorJSONBlockJob(qemuMonitorPtr mon, if (ret == 0 && mode == BLOCK_JOB_INFO) ret = qemuMonitorJSONGetBlockJobInfo(reply, device, info); - if (ret == 0 && mode == BLOCK_JOB_PULL && bandwidth != 0) - ret = qemuMonitorJSONBlockJob(mon, device, bandwidth, NULL, - BLOCK_JOB_SPEED); - virJSONValueFree(cmd); virJSONValueFree(reply); return ret; -- 1.7.3

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[libvirt] [PATCH] Increase size of buffer for xend response
by Jim Fehlig 02 Sep '11

02 Sep '11

On systems with many pcpus, the sexpr returned by xend can be quite large for dom0 when it is configured to have #vcpus = #pcpus (default). E.g. on a 80 pcpu system, where dom0 had 80 vcpus, the sexpr details for dom0 was 73817 bytes! Increase maximum buffer size to 256k. --- 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 957cd17..1fdebe1 100644 --- a/src/xen/xend_internal.c +++ b/src/xen/xend_internal.c @@ -56,7 +56,7 @@ * The number of Xen scheduler parameters */ -#define XEND_RCV_BUF_MAX_LEN 65536 +#define XEND_RCV_BUF_MAX_LEN 262144 static int virDomainXMLDevID(virDomainPtr domain, -- 1.7.5.4

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[libvirt] [PATCH] Don't overwrite errors from xend_{get,req}
by Jim Fehlig 02 Sep '11

02 Sep '11

xenDaemonDomainFetch() was overwriting errors reported by xend_get() and xend_req(). E.g. without patch error: failed Xen syscall xenDaemonDomainFetch failed to find this domain with patch error: internal error Xend returned HTTP Content-Length of 73817, which exceeds maximum of 65536 --- src/xen/xend_internal.c | 12 +++++------- 1 files changed, 5 insertions(+), 7 deletions(-) diff --git a/src/xen/xend_internal.c b/src/xen/xend_internal.c index f44d674..957cd17 100644 --- a/src/xen/xend_internal.c +++ b/src/xen/xend_internal.c @@ -359,8 +359,10 @@ xend_get(virConnectPtr xend, const char *path, ret = xend_req(s, content); VIR_FORCE_CLOSE(s); - if (((ret < 0) || (ret >= 300)) && - ((ret != 404) || (!STRPREFIX(path, "/xend/domain/")))) { + if (ret < 0) + return ret; + + if ((ret >= 300) && ((ret != 404) || (!STRPREFIX(path, "/xend/domain/")))) { virXendError(VIR_ERR_GET_FAILED, _("%d status from xen daemon: %s:%s"), ret, path, NULLSTR(*content)); @@ -1810,12 +1812,8 @@ xenDaemonDomainFetch(virConnectPtr conn, root = sexpr_get(conn, "/xend/domain/%s?detail=1", name); else root = sexpr_get(conn, "/xend/domain/%d?detail=1", domid); - if (root == NULL) { - virXendError(VIR_ERR_XEN_CALL, - "%s", _("xenDaemonDomainFetch failed to" - " find this domain")); + if (root == NULL) return (NULL); - } priv = (xenUnifiedPrivatePtr) conn->privateData; -- 1.7.5.4

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[libvirt] [PATCH] Change my email domain
by Jim Fehlig 01 Sep '11

01 Sep '11

I'd like to change my primary email address to jfehlig(a)suse.com. This patch changes it in AUTHORS and .mailmap. --- .mailmap | 3 ++- AUTHORS | 2 +- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/.mailmap b/.mailmap index cdfd9fd..2795047 100644 --- a/.mailmap +++ b/.mailmap @@ -13,7 +13,8 @@ <meyering(a)redhat.com> <jim(a)meyering.net> <socketpair(a)gmail.com> <socketpair gmail com> <soren(a)linux2go.dk> <soren(a)ubuntu.com> -<jfehlig(a)novell.com> <jfehlig(a)linux-ypgk.site> +<jfehlig(a)suse.com> <jfehlig(a)novell.com> +<jfehlig(a)suse.com> <jfehlig(a)linux-ypgk.site> <jclift(a)redhat.com> <justin(a)salasaga.org> <berrange(a)redhat.com> <dan(a)berrange.com> <soren(a)linux2go.dk> <soren(a)canonical.com> diff --git a/AUTHORS b/AUTHORS index 6cf2cd5..3dc34e9 100644 --- a/AUTHORS +++ b/AUTHORS @@ -13,7 +13,7 @@ The primary maintainers and people with commit access rights: Mark McLoughlin <markmc(a)redhat.com> Anthony Liguori <aliguori(a)us.ibm.com> Jim Meyering <meyering(a)redhat.com> - Jim Fehlig <jfehlig(a)novell.com> + Jim Fehlig <jfehlig(a)suse.com> Chris Lalancette <clalance(a)redhat.com> Cole Robinson <crobinso(a)redhat.com> Guido Günther <agx(a)sigxcpu.org> -- 1.7.5.4

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[libvirt] [PATCHv3 00/43] cleaned up snapshot series
by Eric Blake 01 Sep '11

01 Sep '11

As promised, here is my v3, which includes all the self-replies I was scattering throughout v2: https://www.redhat.com/archives/libvir-list/2011-August/msg00620.html Also available here: git fetch git://repo.or.cz/libvirt/ericb.git snapshot or browse online at: http://repo.or.cz/w/libvirt/ericb.git/shortlog/refs/heads/snapshot I've tested that this can create external disk snapshots with SELinux running using the qemu snapshot_blkdev monitor command, then deleting the metadata for those snapshots. Other things from my RFC still remain to be coded: https://www.redhat.com/archives/libvir-list/2011-August/msg00361.html support for offline external disk snapshots support for more flags (such as starting an offline snapshot on revert) support for revert and delete of disk snapshots new apis for easier manipulation of snapshot hierarchies Eric Blake (43): snapshot: better event when reverting qemu to paused snapshot snapshot: improve reverting to qemu paused snapshots snapshot: properly revert qemu to offline snapshots snapshot: don't leak resources on qemu snapshot failure snapshot: only pass snapshot to qemu command line when reverting snapshot: track current snapshot across restarts snapshot: allow deletion of just snapshot metadata snapshot: avoid crash when deleting qemu snapshots snapshot: simplify acting on just children snapshot: let qemu discard only snapshot metadata snapshot: identify which snapshots have metadata snapshot: identify qemu snapshot roots snapshot: prevent stranding snapshot data on domain destruction snapshot: refactor some qemu code snapshot: cache qemu-img location snapshot: support new undefine flags in qemu snapshot: teach virsh about new undefine flags snapshot: prevent migration from stranding snapshot data snapshot: refactor domain xml output snapshot: allow full domain xml in snapshot snapshot: correctly escape generated xml snapshot: update rng to support full domain in xml snapshot: store qemu domain details in xml snapshot: additions to domain xml for disks snapshot: reject transient disks where code is not ready snapshot: reflect recent options in virsh snapshot: introduce new deletion flag snapshot: expose new delete flag in virsh snapshot: allow halting after snapshot snapshot: refactor virsh snapshot creation snapshot: expose halt-after-creation in virsh snapshot: wire up new qemu monitor command snapshot: support extra state in snapshots snapshot: add <disks> to snapshot xml snapshot: also support disks by path snapshot: add virsh domblklist command snapshot: add flag for requesting disk snapshot snapshot: reject unimplemented disk snapshot features snapshot: make it possible to audit external snapshot snapshot: wire up disk-only flag to snapshot-create snapshot: wire up live qemu disk snapshots snapshot: refactor qemu file opening snapshot: use SELinux and lock manager with external snapshots docs/formatdomain.html.in | 40 +- docs/formatsnapshot.html.in | 253 ++- docs/schemas/Makefile.am | 1 + docs/schemas/domain.rng | 2555 +------------------- docs/schemas/{domain.rng => domaincommon.rng} | 32 +- docs/schemas/domainsnapshot.rng | 89 +- include/libvirt/libvirt.h.in | 62 +- src/conf/domain_audit.c | 12 +- src/conf/domain_audit.h | 4 +- src/conf/domain_conf.c | 861 ++++++-- src/conf/domain_conf.h | 75 +- src/esx/esx_driver.c | 41 +- src/libvirt.c | 132 +- src/libvirt_private.syms | 8 + src/libxl/libxl_conf.c | 5 + src/libxl/libxl_driver.c | 11 +- src/qemu/qemu_command.c | 12 +- src/qemu/qemu_conf.h | 1 + src/qemu/qemu_driver.c | 1611 +++++++++---- src/qemu/qemu_hotplug.c | 18 +- src/qemu/qemu_migration.c | 2 +- src/qemu/qemu_monitor.c | 24 + src/qemu/qemu_monitor.h | 4 + src/qemu/qemu_monitor_json.c | 33 + src/qemu/qemu_monitor_json.h | 4 + src/qemu/qemu_monitor_text.c | 40 + src/qemu/qemu_monitor_text.h | 4 + src/qemu/qemu_process.c | 21 +- src/qemu/qemu_process.h | 1 + src/uml/uml_driver.c | 56 +- src/vbox/vbox_tmpl.c | 46 +- src/xen/xend_internal.c | 12 +- src/xenxs/xen_sxpr.c | 5 + src/xenxs/xen_xm.c | 5 + tests/domainsnapshotxml2xmlin/disk_snapshot.xml | 16 + tests/domainsnapshotxml2xmlout/disk_snapshot.xml | 77 + tests/domainsnapshotxml2xmlout/full_domain.xml | 35 + .../qemuxml2argv-disk-snapshot.args | 7 + .../qemuxml2argv-disk-snapshot.xml | 39 + .../qemuxml2argv-disk-transient.xml | 27 + tests/qemuxml2argvtest.c | 2 + tools/virsh.c | 755 +++++- tools/virsh.pod | 111 +- 43 files changed, 3616 insertions(+), 3533 deletions(-) copy docs/schemas/{domain.rng => domaincommon.rng} (98%) create mode 100644 tests/domainsnapshotxml2xmlin/disk_snapshot.xml create mode 100644 tests/domainsnapshotxml2xmlout/disk_snapshot.xml create mode 100644 tests/domainsnapshotxml2xmlout/full_domain.xml create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-snapshot.args create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-snapshot.xml create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-transient.xml -- 1.7.4.4

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[libvirt] Problems with "attach-interface" command of libvirt
by Tao Siheng 01 Sep '11

01 Sep '11

Dear libvirt-developer: I'm a student of computer science and technology in China. I encountered a problem when I want to attach a bridge to an existed Virtual Machine. I used the command "attach-interface domain_id bridge br0 --target tap0". "br0" was created by brctl and "tap0" was created by tunctl.Here is the error information: error: Failed to attach interface error: internal error unable to send TAP file handle: No file descriptor supplied via SCM_RIGHTS. I know there are some bugs in the earlier version of libvirt. So I upgraded the ubuntu kernel to 2.6.38.8 and added the module "macvtap" by the using the command "sudo modprobe macvtap". I have installed libvirt0.8.8, QEMU 0.8.8 and QEMU 0.12.3.Although I did all the above, the problem is still not solved. I need your help sincerely. Tao Siheng 2011.9.1

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