[libvirt-users] Fail in virDomainUpdateDeviceFlags (libvirt-4.0.0 + Qemu-kvm 2.9.0 + Ceph 10.2.10)

Hello Everyone, My pc run in CentOS 7.4 and install libvirt-4.0.0 + Qemu-kvm 2.9.0 + Ceph 10.2.10 ALL-in-One. I use python-sdk with libvirt and run [self.domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_LIVE)] on CDROM (I want to change media path). However, I enable libvirt debug log , the log as below: "2018-02-26 13:09:13.638+0000: 50524: debug : virDomainLookupByName:412 : conn=0x7f7278000aa0, name=6ec499397d594ef2a64fcfc938f38225 2018-02-26 13:09:13.638+0000: 50515: debug : virDomainGetInfo:2431 : dom=0x7f726c000c30, (VM: name=6ec499397d594ef2a64fcfc938f38225, uuid=6ec49939-7d59-4ef2-a64f-cfc938f38225), info=0x7f72b9059b20 2018-02-26 13:09:13.638+0000: 50515: debug : qemuGetProcessInfo:1479 : Got status for 71205/0 user=14674 sys=3627 cpu=5 rss=105105 2018-02-26 13:09:13.644+0000: 50519: debug : virDomainGetXMLDesc:2572 : dom=0x7f7280002f20, (VM: name=6ec499397d594ef2a64fcfc938f38225, uuid=6ec49939-7d59-4ef2-a64f-cfc938f38225), flags=0x0 2018-02-26 13:09:13.653+0000: 50516: debug : virDomainUpdateDeviceFlags:8326 : dom=0x7f7274000b90, (VM: name=6ec499397d594ef2a64fcfc938f38225, uuid=6ec49939-7d59-4ef2-a64f-cfc938f38225), xml=<disk device="cdrom" type="network"><source name="zstack/08085a31f8c43f278ed2f649ee166b1f@08085a31f8c43f278ed2f649ee166b 1f" protocol="rbd"><host name="10.0.229.181" port="6789" /></source><auth username="zstack"><secret type="ceph" uuid="9b06bb70-dc13-4338-88fd-b0c72d5ab9e9" /></auth><target bus="ide" dev="hdc" /><readonly /></disk>, flags=0x1 2018-02-26 13:09:13.653+0000: 50516: debug : qemuDomainObjBeginJobInternal:4778 : Starting job: modify (vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225, current job=none async=none) 2018-02-26 13:09:13.653+0000: 50516: debug : qemuDomainObjBeginJobInternal:4819 : Started job: modify (async=none vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225) 2018-02-26 13:09:13.660+0000: 50516: debug : virQEMUCapsCacheLookup:5443 : Returning caps 0x7f7294126ac0 for /usr/libexec/qemu-kvm 2018-02-26 13:09:13.664+0000: 50516: debug : virQEMUCapsCacheLookup:5443 : Returning caps 0x7f7294126ac0 for /usr/libexec/qemu-kvm 2018-02-26 13:09:13.667+0000: 50516: debug : qemuSetupImageCgroupInternal:91 : Not updating cgroups for disk path '08085a31f8c43f278ed2f649ee166b1f@08085a31f8c43f278ed2f649ee166b1f', type: network 2018-02-26 13:09:13.667+0000: 50516: debug : qemuDomainObjEnterMonitorInternal:5048 : Entering monitor (mon=0x7f728c07f260 vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225) 2018-02-26 13:09:13.667+0000: 50516: debug : qemuMonitorEjectMedia:2487 : dev_name=drive-ide0-1-0 force=0 2018-02-26 13:09:13.667+0000: 50516: debug : qemuMonitorEjectMedia:2489 : mon:0x7f728c07f260 vm:0x7f7294100af0 json:1 fd:24 2018-02-26 13:09:13.667+0000: 50516: debug : qemuMonitorJSONCommandWithFd:301 : Send command '{"execute":"eject","arguments":{"device":"drive-ide0-1-0","force":false},"i d":"libvirt-78"}' for write with FD -1 2018-02-26 13:09:13.667+0000: 50516: info : qemuMonitorSend:1079 : QEMU_MONITOR_SEND_MSG: mon=0x7f728c07f260 msg={"execute":"eject","arguments":{"device":"drive-ide0-1-0","force":false} ,"id":"libvirt-78"} fd=-1 2018-02-26 13:09:13.667+0000: 50514: info : qemuMonitorIOWrite:553 : QEMU_MONITOR_IO_WRITE: mon=0x7f728c07f260 buf={"execute":"eject","arguments":{"device":"drive-ide0-1-0","force":false} ,"id":"libvirt-78"} len=93 ret=93 errno=0 2018-02-26 13:09:13.669+0000: 50514: debug : qemuMonitorJSONIOProcessLine:193 : Line [{"return": {}, "id": "libvirt-78"}] 2018-02-26 13:09:13.669+0000: 50514: info : qemuMonitorJSONIOProcessLine:213 : QEMU_MONITOR_RECV_REPLY: mon=0x7f728c07f260 reply={"return": {}, "id": "libvirt-78"} 2018-02-26 13:09:13.669+0000: 50516: debug : qemuMonitorJSONCommandWithFd:306 : Receive command reply ret=0 rxObject=0x5561b7c6abc0 2018-02-26 13:09:13.669+0000: 50516: debug : qemuDomainObjExitMonitorInternal:5071 : Exited monitor (mon=0x7f728c07f260 vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225) 2018-02-26 13:09:13.669+0000: 50516: debug : qemuDomainObjEnterMonitorInternal:5048 : Entering monitor (mon=0x7f728c07f260 vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225) 2018-02-26 13:09:13.669+0000: 50516: debug : qemuMonitorEjectMedia:2487 : dev_name=drive-ide0-1-0 force=0 2018-02-26 13:09:13.669+0000: 50516: debug : qemuMonitorEjectMedia:2489 : mon:0x7f728c07f260 vm:0x7f7294100af0 json:1 fd:24 2018-02-26 13:09:13.669+0000: 50516: debug : qemuMonitorJSONCommandWithFd:301 : Send command '{"execute":"eject","arguments":{"device":"drive-ide0-1-0","force":false},"i d":"libvirt-79"}' for write with FD -1 2018-02-26 13:09:13.669+0000: 50516: info : qemuMonitorSend:1079 : QEMU_MONITOR_SEND_MSG: mon=0x7f728c07f260 msg={"execute":"eject","arguments":{"device":"drive-ide0-1-0","force":false} ,"id":"libvirt-79"} fd=-1 2018-02-26 13:09:13.669+0000: 50514: info : qemuMonitorIOWrite:553 : QEMU_MONITOR_IO_WRITE: mon=0x7f728c07f260 buf={"execute":"eject","arguments":{"device":"drive-ide0-1-0","force":false} ,"id":"libvirt-79"} len=93 ret=93 errno=0 2018-02-26 13:09:13.670+0000: 50514: debug : qemuMonitorJSONIOProcessLine:193 : Line [{"return": {}, "id": "libvirt-79"}] 2018-02-26 13:09:13.670+0000: 50514: info : qemuMonitorJSONIOProcessLine:213 : QEMU_MONITOR_RECV_REPLY: mon=0x7f728c07f260 reply={"return": {}, "id": "libvirt-79"} 2018-02-26 13:09:13.670+0000: 50516: debug : qemuMonitorJSONCommandWithFd:306 : Receive command reply ret=0 rxObject=0x5561b7c6a080 2018-02-26 13:09:13.670+0000: 50516: debug : qemuDomainObjExitMonitorInternal:5071 : Exited monitor (mon=0x7f728c07f260 vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225) 2018-02-26 13:09:13.670+0000: 50516: debug : qemuDomainObjEnterMonitorInternal:5048 : Entering monitor (mon=0x7f728c07f260 vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225) 2018-02-26 13:09:13.670+0000: 50516: debug : qemuMonitorChangeMedia:2504 : dev_name=drive-ide0-1-0 newmedia=rbd:zstack/08085a31f8c43f278ed2f649ee166b1f@08085a31f8c43f278ed2f64 9ee166b1f:auth_supported=none:mon_host=10.0.229.181\:6789 format=raw 2018-02-26 13:09:13.670+0000: 50516: debug : qemuMonitorChangeMedia:2506 : mon:0x7f728c07f260 vm:0x7f7294100af0 json:1 fd:24 2018-02-26 13:09:13.670+0000: 50516: debug : qemuMonitorJSONCommandWithFd:301 : Send command '{"execute":"change","arguments":{"device":"drive-ide0-1-0","target":"rbd:zs tack/08085a31f8c43f278ed2f649ee166b1f@08085a31f8c43f278ed2f649ee166b1f:auth_ supported=none:mon_host=10.0.229.181\\:6789","arg":"raw"},"id":"libvirt-80"} ' for write with FD -1 2018-02-26 13:09:13.670+0000: 50516: info : qemuMonitorSend:1079 : QEMU_MONITOR_SEND_MSG: mon=0x7f728c07f260 msg={"execute":"change","arguments":{"device":"drive-ide0-1-0","target":"rbd :zstack/08085a31f8c43f278ed2f649ee166b1f@08085a31f8c43f278ed2f649ee166b1f:au th_supported=none:mon_host=10.0.229.181\\:6789","arg":"raw"},"id":"libvirt-8 0"} fd=-1 2018-02-26 13:09:13.670+0000: 50514: info : qemuMonitorIOWrite:553 : QEMU_MONITOR_IO_WRITE: mon=0x7f728c07f260 buf={"execute":"change","arguments":{"device":"drive-ide0-1-0","target":"rbd :zstack/08085a31f8c43f278ed2f649ee166b1f@08085a31f8c43f278ed2f649ee166b1f:au th_supported=none:mon_host=10.0.229.181\\:6789","arg":"raw"},"id":"libvirt-8 0"} len=229 ret=229 errno=0 2018-02-26 13:09:13.678+0000: 50514: debug : qemuMonitorJSONIOProcessLine:193 : Line [{"id": "libvirt-80", "error": {"class": "GenericError", "desc": "error connecting: Operation not supported"}}] 2018-02-26 13:09:13.678+0000: 50514: info : qemuMonitorJSONIOProcessLine:213 : QEMU_MONITOR_RECV_REPLY: mon=0x7f728c07f260 reply={"id": "libvirt-80", "error": {"class": "GenericError", "desc": "error connecting: Operation not supported"}} 2018-02-26 13:09:13.678+0000: 50516: debug : qemuMonitorJSONCommandWithFd:306 : Receive command reply ret=0 rxObject=0x5561b7c88f40 2018-02-26 13:09:13.678+0000: 50516: debug : qemuMonitorJSONCheckError:381 : unable to execute QEMU command {"execute":"change","arguments":{"device":"drive-ide0-1-0","target":"rbd:zst ack/08085a31f8c43f278ed2f649ee166b1f@08085a31f8c43f278ed2f649ee166b1f:auth_s upported=none:mon_host=10.0.229.181\\:6789","arg":"raw"},"id":"libvirt-80"}: {"id":"libvirt-80","error":{"class":"GenericError","desc":"error connecting: Operation not supported"}} 2018-02-26 13:09:13.678+0000: 50516: error : qemuMonitorJSONCheckError:392 : internal error: unable to execute QEMU command 'change': error connecting: Operation not supported 2018-02-26 13:09:13.678+0000: 50516: debug : qemuDomainObjExitMonitorInternal:5071 : Exited monitor (mon=0x7f728c07f260 vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225) 2018-02-26 13:09:13.678+0000: 50516: debug : qemuTeardownImageCgroup:123 : Not updating cgroups for disk path '08085a31f8c43f278ed2f649ee166b1f@08085a31f8c43f278ed2f649ee166b1f', type: network 2018-02-26 13:09:13.682+0000: 50516: debug : qemuDomainObjEndJob:4979 : Stopping job: modify (async=none vm=0x7f7294100af0 name=6ec499397d594ef2a64fcfc938f38225) 2018-02-26 13:09:13.983+0000: 50520: debug : virDomainLookupByName:412 : conn=0x7f7278000aa0, name=6ec499397d594ef2a64fcfc938f38225 2018-02-26 13:09:13.990+0000: 50518: debug : virDomainGetInfo:2431 : dom=0x7f72700009b0, (VM: name=6ec499397d594ef2a64fcfc938f38225, uuid=6ec49939-7d59-4ef2-a64f-cfc938f38225), info=0x7f72b7856b20 2018-02-26 13:09:13.990+0000: 50518: debug : qemuGetProcessInfo:1479 : Got status for 71205/0 user=14675 sys=3628 cpu=0 rss=105119 2018-02-26 13:09:13.991+0000: 50515: debug : virDomainGetXMLDesc:2572 : dom=0x7f726c000c30, (VM: name=6ec499397d594ef2a64fcfc938f38225, uuid=6ec49939-7d59-4ef2-a64f-cfc938f38225), flags=0x0" I see the flow is virDomainUpdateDeviceFlags -> qemuMonitorChangeMedia, but the cephx auth is drop, so make update error. Anybody meet this error? Best Regards, Star Guo

On 02/27/2018 03:06 AM, Star Guo wrote:
Hello Everyone,
My pc run in CentOS 7.4 and install libvirt-4.0.0 + Qemu-kvm 2.9.0 + Ceph 10.2.10 ALL-in-One.
I use python-sdk with libvirt and run [self.domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_LIVE)] on CDROM (I want to change media path). However, I enable libvirt debug log , the log as below:
<snip/>
I see the flow is virDomainUpdateDeviceFlags -> qemuMonitorChangeMedia, but the cephx auth is drop, so make update error. Anybody meet this error?
Yes, this is a libvirt bug. I think this fixes the issue: diff --git i/src/qemu/qemu_driver.c w/src/qemu/qemu_driver.c index 96454c17c..0e5ad9971 100644 --- i/src/qemu/qemu_driver.c +++ w/src/qemu/qemu_driver.c @@ -7842,6 +7842,8 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, virQEMUDriverPtr driver, bool force) { + virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); + qemuDomainObjPrivatePtr priv = vm->privateData; virDomainDiskDefPtr disk = dev->data.disk; virDomainDiskDefPtr orig_disk = NULL; virDomainDeviceDef oldDev = { .type = dev->type }; @@ -7850,6 +7852,9 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, if (virDomainDiskTranslateSourcePool(disk) < 0) goto cleanup; + if (qemuDomainPrepareDiskSource(disk, priv, cfg) < 0) + goto cleanup; + if (qemuDomainDetermineDiskChain(driver, vm, disk, false, true) < 0) goto cleanup; @@ -7898,6 +7903,7 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, ret = 0; cleanup: + virObjectUnref(cfg); return ret; } Can you check and confirm? Michal

On Tue, Feb 27, 2018 at 09:53:00 +0100, Michal Privoznik wrote:
On 02/27/2018 03:06 AM, Star Guo wrote:
Hello Everyone,
My pc run in CentOS 7.4 and install libvirt-4.0.0 + Qemu-kvm 2.9.0 + Ceph 10.2.10 ALL-in-One.
I use python-sdk with libvirt and run [self.domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_LIVE)] on CDROM (I want to change media path). However, I enable libvirt debug log , the log as below:
<snip/>
I see the flow is virDomainUpdateDeviceFlags -> qemuMonitorChangeMedia, but the cephx auth is drop, so make update error. Anybody meet this error?
Yes, this is a libvirt bug. I think this fixes the issue:
diff --git i/src/qemu/qemu_driver.c w/src/qemu/qemu_driver.c index 96454c17c..0e5ad9971 100644 --- i/src/qemu/qemu_driver.c +++ w/src/qemu/qemu_driver.c @@ -7842,6 +7842,8 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, virQEMUDriverPtr driver, bool force) { + virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); + qemuDomainObjPrivatePtr priv = vm->privateData; virDomainDiskDefPtr disk = dev->data.disk; virDomainDiskDefPtr orig_disk = NULL; virDomainDeviceDef oldDev = { .type = dev->type }; @@ -7850,6 +7852,9 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, if (virDomainDiskTranslateSourcePool(disk) < 0) goto cleanup;
+ if (qemuDomainPrepareDiskSource(disk, priv, cfg) < 0) + goto cleanup;
It's not that easy. At this point you also need to hotplug the 'secret' object. Without that the command will fail as the secret object referenced by the storage source definition will not be present. There should be a upstream bugzilla tracking this and I'm planing to fix this during my work on using the new blockdev stuff in qemu.

On 03/02/2018 08:28 AM, Peter Krempa wrote:
On Tue, Feb 27, 2018 at 09:53:00 +0100, Michal Privoznik wrote:
On 02/27/2018 03:06 AM, Star Guo wrote:
Hello Everyone,
My pc run in CentOS 7.4 and install libvirt-4.0.0 + Qemu-kvm 2.9.0 + Ceph 10.2.10 ALL-in-One.
I use python-sdk with libvirt and run [self.domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_LIVE)] on CDROM (I want to change media path). However, I enable libvirt debug log , the log as below:
<snip/>
I see the flow is virDomainUpdateDeviceFlags -> qemuMonitorChangeMedia, but the cephx auth is drop, so make update error. Anybody meet this error?
Yes, this is a libvirt bug. I think this fixes the issue:
diff --git i/src/qemu/qemu_driver.c w/src/qemu/qemu_driver.c index 96454c17c..0e5ad9971 100644 --- i/src/qemu/qemu_driver.c +++ w/src/qemu/qemu_driver.c @@ -7842,6 +7842,8 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, virQEMUDriverPtr driver, bool force) { + virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); + qemuDomainObjPrivatePtr priv = vm->privateData; virDomainDiskDefPtr disk = dev->data.disk; virDomainDiskDefPtr orig_disk = NULL; virDomainDeviceDef oldDev = { .type = dev->type }; @@ -7850,6 +7852,9 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, if (virDomainDiskTranslateSourcePool(disk) < 0) goto cleanup;
+ if (qemuDomainPrepareDiskSource(disk, priv, cfg) < 0) + goto cleanup;
It's not that easy. At this point you also need to hotplug the 'secret' object. Without that the command will fail as the secret object referenced by the storage source definition will not be present.
Just because it may not be obvious that the thread forked (probably email client for original poster)... Anyway, see what ended up being a longer explanation here: https://www.redhat.com/archives/libvirt-users/2018-February/msg00086.html Where the short story is I don't think you need to hotplug a secret object as that should already be there. One cannot hotplug a cdrom, so the definition and the secret used must already exist. It's a strange code path and while looking I didn't find a mechanism that would allow an "empty" or "tray='open'" to actually create a dummy entry. I believe there needs to be a way via the (newer, but not supported in libvirt) blockdev-change-medium qmp command to tell it what the secret object id is.
There should be a upstream bugzilla tracking this and I'm planing to fix this during my work on using the new blockdev stuff in qemu.
And yes, bzs would be good to track all this. John

On Fri, Mar 02, 2018 at 15:32:44 -0500, John Ferlan wrote:
On 03/02/2018 08:28 AM, Peter Krempa wrote:
On Tue, Feb 27, 2018 at 09:53:00 +0100, Michal Privoznik wrote:
On 02/27/2018 03:06 AM, Star Guo wrote:
Hello Everyone,
My pc run in CentOS 7.4 and install libvirt-4.0.0 + Qemu-kvm 2.9.0 + Ceph 10.2.10 ALL-in-One.
I use python-sdk with libvirt and run [self.domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_LIVE)] on CDROM (I want to change media path). However, I enable libvirt debug log , the log as below:
<snip/>
I see the flow is virDomainUpdateDeviceFlags -> qemuMonitorChangeMedia, but the cephx auth is drop, so make update error. Anybody meet this error?
Yes, this is a libvirt bug. I think this fixes the issue:
diff --git i/src/qemu/qemu_driver.c w/src/qemu/qemu_driver.c index 96454c17c..0e5ad9971 100644 --- i/src/qemu/qemu_driver.c +++ w/src/qemu/qemu_driver.c @@ -7842,6 +7842,8 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, virQEMUDriverPtr driver, bool force) { + virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); + qemuDomainObjPrivatePtr priv = vm->privateData; virDomainDiskDefPtr disk = dev->data.disk; virDomainDiskDefPtr orig_disk = NULL; virDomainDeviceDef oldDev = { .type = dev->type }; @@ -7850,6 +7852,9 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, if (virDomainDiskTranslateSourcePool(disk) < 0) goto cleanup;
+ if (qemuDomainPrepareDiskSource(disk, priv, cfg) < 0) + goto cleanup;
It's not that easy. At this point you also need to hotplug the 'secret' object. Without that the command will fail as the secret object referenced by the storage source definition will not be present.
Just because it may not be obvious that the thread forked (probably email client for original poster)... Anyway, see what ended up being a longer explanation here:
https://www.redhat.com/archives/libvirt-users/2018-February/msg00086.html
Where the short story is I don't think you need to hotplug a secret object as that should already be there. One cannot hotplug a cdrom, so the definition and the secret used must already exist. It's a strange
No, no, no. That is plain wrong. The secret object is property of the image and not the drive. If you change the image you need to unplug all old encryption and authentication secrets and plug back new ones. That was the reason why I insisted so much that you actually make it a member of virStorageSource.
code path and while looking I didn't find a mechanism that would allow an "empty" or "tray='open'" to actually create a dummy entry.
I believe there needs to be a way via the (newer, but not supported in libvirt) blockdev-change-medium qmp command to tell it what the secret object id is.
The object id of the secret is added via blockdev-add. Blockdev-change-medium then uses that node as a media for the drive.
There should be a upstream bugzilla tracking this and I'm planing to fix this during my work on using the new blockdev stuff in qemu.
And yes, bzs would be good to track all this.
John

On 03/05/2018 03:47 AM, Peter Krempa wrote:
On Fri, Mar 02, 2018 at 15:32:44 -0500, John Ferlan wrote:
On 03/02/2018 08:28 AM, Peter Krempa wrote:
On Tue, Feb 27, 2018 at 09:53:00 +0100, Michal Privoznik wrote:
On 02/27/2018 03:06 AM, Star Guo wrote:
Hello Everyone,
My pc run in CentOS 7.4 and install libvirt-4.0.0 + Qemu-kvm 2.9.0 + Ceph 10.2.10 ALL-in-One.
I use python-sdk with libvirt and run [self.domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_LIVE)] on CDROM (I want to change media path). However, I enable libvirt debug log , the log as below:
<snip/>
I see the flow is virDomainUpdateDeviceFlags -> qemuMonitorChangeMedia, but the cephx auth is drop, so make update error. Anybody meet this error?
Yes, this is a libvirt bug. I think this fixes the issue:
diff --git i/src/qemu/qemu_driver.c w/src/qemu/qemu_driver.c index 96454c17c..0e5ad9971 100644 --- i/src/qemu/qemu_driver.c +++ w/src/qemu/qemu_driver.c @@ -7842,6 +7842,8 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, virQEMUDriverPtr driver, bool force) { + virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); + qemuDomainObjPrivatePtr priv = vm->privateData; virDomainDiskDefPtr disk = dev->data.disk; virDomainDiskDefPtr orig_disk = NULL; virDomainDeviceDef oldDev = { .type = dev->type }; @@ -7850,6 +7852,9 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, if (virDomainDiskTranslateSourcePool(disk) < 0) goto cleanup;
+ if (qemuDomainPrepareDiskSource(disk, priv, cfg) < 0) + goto cleanup;
It's not that easy. At this point you also need to hotplug the 'secret' object. Without that the command will fail as the secret object referenced by the storage source definition will not be present.
Just because it may not be obvious that the thread forked (probably email client for original poster)... Anyway, see what ended up being a longer explanation here:
https://www.redhat.com/archives/libvirt-users/2018-February/msg00086.html
Where the short story is I don't think you need to hotplug a secret object as that should already be there. One cannot hotplug a cdrom, so the definition and the secret used must already exist. It's a strange
No, no, no. That is plain wrong. The secret object is property of the image and not the drive. If you change the image you need to unplug all old encryption and authentication secrets and plug back new ones.
Well... Kind of... Perhaps it's a matter of how I phrased things. Yes, I agree the secret is associated with the image and not the drive; however, the image is part of the drive command. So while technically there is a split, my description didn't make that distinction mainly because when it comes to the change commands all that matters is the "filename" (or target) that's being changed and not the server. Since, the authentication is to/for the server and changing the "filename" does not make it possible to change the "server", just which file on the server is being used. Thus, even if you unplugged the old encryption and authentication secret and plugged a new one in, AFAICT the "blockdev-change-medium" command provides no mechanism to use the secrets. There is no parsing of server and secret options. Perhaps it's better to provide an example. Using an example since I have iSCSI set up, when first started... -object secret,id=ide0-0-1-secret0,..., -drive file.driver=iscsi,file... {portal=, target=, lun=, transport=, user=, file.password-secret=ide0-0-1-secret0}...,id=drive-ide0-0-1,... -device ide-cd,bus=ide.0,...drive=drive-ide0-0-1,id=ide0-0-1 In order to open the iSCSI (or RBD) device the "file.password-secret" command option of the "-drive" command describes the secret object id to be used during the backend driver open (e.g. target of bdrv_file_open) - using the example above "ide0-0-1-secret0". It's not the -drive command id/alias (or "drive-ide0-0-1"). The file that gets opened on the server would be the "file.target=" value. The "change" command passes the device or drive alias ("drive-ide0-0-1"), the target or new source path, and an arg for format. Internally to qemu, the change command "converts" into the blockdev-change-medium. The "blockdev-change-medium" takes similar options, but notes that the device (e.g. drive alias) is deprecated in favor of an "id=" option (although it still accepts the device if provided). AFAICT, the "id" option is not used in libvirt yet. The block_set_io_throttle being the example I looked at. Following the code for using the "id" option, I see no connection to the secret object which would store the server passphrase. So when the bdrv_open is called from qmp_blockdev_change_medium, there is no way to "connect" to the alias. If it happens differently than that, then please show me what I'm missing.
That was the reason why I insisted so much that you actually make it a member of virStorageSource.
code path and while looking I didn't find a mechanism that would allow an "empty" or "tray='open'" to actually create a dummy entry.
I believe there needs to be a way via the (newer, but not supported in libvirt) blockdev-change-medium qmp command to tell it what the secret object id is.
The object id of the secret is added via blockdev-add. Blockdev-change-medium then uses that node as a media for the drive.
The former I see; however, the latter I'm not seeing how that happens. John
There should be a upstream bugzilla tracking this and I'm planing to fix this during my work on using the new blockdev stuff in qemu.
And yes, bzs would be good to track all this.
John

On Mon, Mar 05, 2018 at 11:11:37 -0500, John Ferlan wrote:
On 03/05/2018 03:47 AM, Peter Krempa wrote:
On Fri, Mar 02, 2018 at 15:32:44 -0500, John Ferlan wrote:
On 03/02/2018 08:28 AM, Peter Krempa wrote:
On Tue, Feb 27, 2018 at 09:53:00 +0100, Michal Privoznik wrote:
On 02/27/2018 03:06 AM, Star Guo wrote:
Hello Everyone,
My pc run in CentOS 7.4 and install libvirt-4.0.0 + Qemu-kvm 2.9.0 + Ceph 10.2.10 ALL-in-One.
I use python-sdk with libvirt and run [self.domain.updateDeviceFlags(xml, libvirt.VIR_DOMAIN_AFFECT_LIVE)] on CDROM (I want to change media path). However, I enable libvirt debug log , the log as below:
<snip/>
I see the flow is virDomainUpdateDeviceFlags -> qemuMonitorChangeMedia, but the cephx auth is drop, so make update error. Anybody meet this error?
Yes, this is a libvirt bug. I think this fixes the issue:
diff --git i/src/qemu/qemu_driver.c w/src/qemu/qemu_driver.c index 96454c17c..0e5ad9971 100644 --- i/src/qemu/qemu_driver.c +++ w/src/qemu/qemu_driver.c @@ -7842,6 +7842,8 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, virQEMUDriverPtr driver, bool force) { + virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); + qemuDomainObjPrivatePtr priv = vm->privateData; virDomainDiskDefPtr disk = dev->data.disk; virDomainDiskDefPtr orig_disk = NULL; virDomainDeviceDef oldDev = { .type = dev->type }; @@ -7850,6 +7852,9 @@ qemuDomainChangeDiskLive(virDomainObjPtr vm, if (virDomainDiskTranslateSourcePool(disk) < 0) goto cleanup;
+ if (qemuDomainPrepareDiskSource(disk, priv, cfg) < 0) + goto cleanup;
It's not that easy. At this point you also need to hotplug the 'secret' object. Without that the command will fail as the secret object referenced by the storage source definition will not be present.
Just because it may not be obvious that the thread forked (probably email client for original poster)... Anyway, see what ended up being a longer explanation here:
https://www.redhat.com/archives/libvirt-users/2018-February/msg00086.html
Where the short story is I don't think you need to hotplug a secret object as that should already be there. One cannot hotplug a cdrom, so the definition and the secret used must already exist. It's a strange
No, no, no. That is plain wrong. The secret object is property of the image and not the drive. If you change the image you need to unplug all old encryption and authentication secrets and plug back new ones.
Well... Kind of... Perhaps it's a matter of how I phrased things. Yes, I agree the secret is associated with the image and not the drive; however, the image is part of the drive command. So while technically there is a split, my description didn't make that distinction mainly because when it comes to the change commands all that matters is the "filename" (or target) that's being changed and not the server. Since,
So this is again misleading. The qemu blockdev-change-medium does not only change the "filename" of the image on the same server. The filename argument is a new full target specification including the server. So anything you provide is a new image regardless of whether it changed server or not.
the authentication is to/for the server and changing the "filename" does not make it possible to change the "server", just which file on the server is being used.
That does not matter. It's a different image even on the same server. It can require different authentication or encryption. The fact that in this case it's on the same server with the same authentication does not help much in the general case. Note that even the libvirt API accepts the full XML, so you can specify any possible image.
Thus, even if you unplugged the old encryption and authentication secret and plugged a new one in, AFAICT the "blockdev-change-medium" command provides no mechanism to use the secrets. There is no parsing of server and secret options.
That's true. We need to use 'x-blockdev-insert-medium' which uses blockdev-add and node-names. Note that 'blockdev-change-medium' documents that it's just a combination of blockdev-open-tray, x-blockdev-remove-medium, x-blockdev-insert-medium and blockdev-close-tray. (Also technically it does provide a way to pass secret, since 'filename' is passed to bdrv_open thus you can pass the JSON pseudo-protocol spec to it.)
participants (4)
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John Ferlan
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Michal Privoznik
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Peter Krempa
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Star Guo