[libvirt] [PATCH 2/2] qemu: Drop default channel path during migration
Migration to an older libvirt (pre v1.3.0-175-g7140807) is broken
because older versions of libvirt generated different channel paths and
they didn't drop the default paths when parsing domain XMLs. We'd get
such a nice error message:
internal error: process exited while connecting to monitor:
2016-07-08T15:28:02.665706Z qemu-kvm: -chardev socket,
id=charchannel0,path=/var/lib/libvirt/qemu/channel/target/
domain-3-nest/org.qemu.guest_agent.0,server,nowait: Failed to bind
socket to /var/lib/libvirt/qemu/channel/target/domain-3-nest/
org.qemu.guest_agent.0: No such file or directory
That said, we should not even format the default paths when generating a
migratable XML.
https://bugzilla.redhat.com/show_bug.cgi?id=1320470
Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com>
---
src/qemu/qemu_domain.c | 43 +++++++++++++++++++++++++++----------------
1 file changed, 27 insertions(+), 16 deletions(-)
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 1b0279b..0ef593c 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -2264,6 +2264,29 @@ qemuDomainDefaultNetModel(const virDomainDef *def,
return "rtl8139";
}
+
+/*
+ * Clear auto generated unix socket path, i.e., the one which starts with our
+ * channel directory.
+ */
+static void
+qemuDomainChrDefDropDefaultPath(virDomainChrDefPtr chr,
+ virQEMUDriverPtr driver)
+{
+ virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver);
+
+ if (chr->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL &&
+ chr->targetType == VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_VIRTIO &&
+ chr->source.type == VIR_DOMAIN_CHR_TYPE_UNIX &&
+ chr->source.data.nix.path &&
+ STRPREFIX(chr->source.data.nix.path, cfg->channelTargetDir)) {
+ VIR_FREE(chr->source.data.nix.path);
+ }
+
+ virObjectUnref(cfg);
+}
+
+
static int
qemuDomainDeviceDefPostParse(virDomainDeviceDefPtr dev,
const virDomainDef *def,
@@ -2345,21 +2368,8 @@ qemuDomainDeviceDefPostParse(virDomainDeviceDefPtr dev,
/* clear auto generated unix socket path for inactive definitions */
if ((parseFlags & VIR_DOMAIN_DEF_PARSE_INACTIVE) &&
- dev->type == VIR_DOMAIN_DEVICE_CHR &&
- dev->data.chr->deviceType == VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL &&
- dev->data.chr->targetType == VIR_DOMAIN_CHR_CHANNEL_TARGET_TYPE_VIRTIO
&&
- dev->data.chr->source.type == VIR_DOMAIN_CHR_TYPE_UNIX &&
- dev->data.chr->source.data.nix.path &&
- STRPREFIX(dev->data.chr->source.data.nix.path, cfg->channelTargetDir))
{
- /*
- * If the address is generated by us (starts with our
- * channel dir), we should not keep it in the persistent
- * XML. If libvirt is the one who generated it, users
- * shouldn't care about that. If they do, they are
- * supposed to set it themselves.
- */
- VIR_FREE(dev->data.chr->source.data.nix.path);
- }
+ dev->type == VIR_DOMAIN_DEVICE_CHR)
+ qemuDomainChrDefDropDefaultPath(dev->data.chr, driver);
/* forbid capabilities mode hostdev in this kind of hypervisor */
if (dev->type == VIR_DOMAIN_DEVICE_HOSTDEV &&
@@ -3174,7 +3184,8 @@ qemuDomainDefFormatBuf(virQEMUDriverPtr driver,
virDomainControllerDefFree(usb);
}
-
+ for (i = 0; i < def->nchannels; i++)
+ qemuDomainChrDefDropDefaultPath(def->channels[i], driver);
}
format:
--
2.9.0