Re: [libvirt] RFC: Detaching interface from guest fails with improper error message if no mac given in xml
On 09/29/2017 09:15 AM, Madhu Pavan wrote: > This RFC is regarding https://bugzilla.redhat.com/show_bug.cgi?id=1497054 > > Let's say we have a network interface > > > > > function='0x0'/> > > > and we are trying to detach the above interface with the following > xml(vfpool.xml): > > > > function='0x0'/> > > Detaching the interface returns error: > # virsh detach-device vffuest vfpool.xml > error: Failed to detach device from vfpool.xml > error: operation failed: no device matching mac address > 52:54:00:54:f6:61 found > > Here the mac address is auto-generated as we haven't given in the > vfpool.xml. > And virDomainNetFindIdx will try to match the auto-generated mac address > with > the domain xml. It fails as there will be no match and the error message > says > "no device matching mac address 52:54:00:54:f6:61 found". > > Here in this scenario I see two possible improvements. > 1. As virDomainNetFindIdx search according to mac address and guest side > PCI address (if specified), we can search for PCI address and avoid > mac address search if mac is not given in the xml. As the PCI address > is unique we don't compromise in performance. Well, since I had discussion about (hot) unplug API recently, I still remember that it's documented that users are required to pass the full device XML and not just a portion of it. > 2. Improve error message by saying mac address is missing in the device > xml. But this is an actual bug. We can do better here. Michal -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] RFC: Detaching interface from guest fails with improper error message if no mac given in xml
On Fri, Sep 29, 2017 at 14:18:52 +0530, Madhu Pavan wrote: > > > On 09/29/2017 01:27 PM, Peter Krempa wrote: > > On Fri, Sep 29, 2017 at 12:45:30 +0530, Madhu Pavan wrote: > > > This RFC is regarding https://bugzilla.redhat.com/show_bug.cgi?id=1497054 > > > > > > Let's say we have a network interface > > > > > > > > > > > > > > > > > function='0x0'/> > > > > > > > > > and we are trying to detach the above interface with the following > > > xml(vfpool.xml): > > > > > > > > > > > > > > function='0x0'/> > > > > > > Detaching the interface returns error: > > > # virsh detach-device vffuest vfpool.xml > > > error: Failed to detach device from vfpool.xml > > > error: operation failed: no device matching mac address 52:54:00:54:f6:61 > > > found > > > > > > Here the mac address is auto-generated as we haven't given in the > > > vfpool.xml. > > > And virDomainNetFindIdx will try to match the auto-generated mac address > > > with > > > the domain xml. It fails as there will be no match and the error message > > > says > > > "no device matching mac address 52:54:00:54:f6:61 found". > > > > > > Here in this scenario I see two possible improvements. > > > 1. As virDomainNetFindIdx search according to mac address and guest side > > > PCI address (if specified), we can search for PCI address and avoid > > > mac address search if mac is not given in the xml. As the PCI address > > > is unique we don't compromise in performance. > > > 2. Improve error message by saying mac address is missing in the device > > > xml. > > I think the problem is that the mac address is always generated in the > > device XML parser. Auto assignment of the mac address is necessary when > > the device is added to the VM. When removing, generating the mac address > > is bogus. > > > > I think we need to make sure that no unique ids are added to the parser > > at least in the cases when the XML is parsed for the unplug code path. > I have a patch ready to search according to PCI address in the absence > of mac address. I can make changes to it so that mac address is not > auto-generated. Is this good to proceed in this direction? That patch probably will be necessary as well. The lookup of network devices tries to compare the mac address as the first thing. Since we've never had the option for the mac address to be missing you'll need to fix it. The problem is that you need to not generate the address since you won't be able to tell in the qemu code whether the address was present or not. Also there's the problem that the mac address is always present in the definition object so you are looking for a substantial refactoring job to make sure that it can be missing in some cases. Or at least remember that it was autogenerated. signature.asc Description: PGP signature -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] RFC: Detaching interface from guest fails with improper error message if no mac given in xml
On 09/29/2017 01:27 PM, Peter Krempa wrote: On Fri, Sep 29, 2017 at 12:45:30 +0530, Madhu Pavan wrote: This RFC is regarding https://bugzilla.redhat.com/show_bug.cgi?id=1497054 Let's say we have a network interface and we are trying to detach the above interface with the following xml(vfpool.xml): Detaching the interface returns error: # virsh detach-device vffuest vfpool.xml error: Failed to detach device from vfpool.xml error: operation failed: no device matching mac address 52:54:00:54:f6:61 found Here the mac address is auto-generated as we haven't given in the vfpool.xml. And virDomainNetFindIdx will try to match the auto-generated mac address with the domain xml. It fails as there will be no match and the error message says "no device matching mac address 52:54:00:54:f6:61 found". Here in this scenario I see two possible improvements. 1. As virDomainNetFindIdx search according to mac address and guest side PCI address (if specified), we can search for PCI address and avoid mac address search if mac is not given in the xml. As the PCI address is unique we don't compromise in performance. 2. Improve error message by saying mac address is missing in the device xml. I think the problem is that the mac address is always generated in the device XML parser. Auto assignment of the mac address is necessary when the device is added to the VM. When removing, generating the mac address is bogus. I think we need to make sure that no unique ids are added to the parser at least in the cases when the XML is parsed for the unplug code path. I have a patch ready to search according to PCI address in the absence of mac address. I can make changes to it so that mac address is not auto-generated. Is this good to proceed in this direction? -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] RFC: Detaching interface from guest fails with improper error message if no mac given in xml
On Fri, Sep 29, 2017 at 12:45:30 +0530, Madhu Pavan wrote: > This RFC is regarding https://bugzilla.redhat.com/show_bug.cgi?id=1497054 > > Let's say we have a network interface > > > > > function='0x0'/> > > > and we are trying to detach the above interface with the following > xml(vfpool.xml): > > > > function='0x0'/> > > Detaching the interface returns error: > # virsh detach-device vffuest vfpool.xml > error: Failed to detach device from vfpool.xml > error: operation failed: no device matching mac address 52:54:00:54:f6:61 > found > > Here the mac address is auto-generated as we haven't given in the > vfpool.xml. > And virDomainNetFindIdx will try to match the auto-generated mac address > with > the domain xml. It fails as there will be no match and the error message > says > "no device matching mac address 52:54:00:54:f6:61 found". > > Here in this scenario I see two possible improvements. > 1. As virDomainNetFindIdx search according to mac address and guest side > PCI address (if specified), we can search for PCI address and avoid > mac address search if mac is not given in the xml. As the PCI address > is unique we don't compromise in performance. > 2. Improve error message by saying mac address is missing in the device xml. I think the problem is that the mac address is always generated in the device XML parser. Auto assignment of the mac address is necessary when the device is added to the VM. When removing, generating the mac address is bogus. I think we need to make sure that no unique ids are added to the parser at least in the cases when the XML is parsed for the unplug code path. signature.asc Description: PGP signature -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
[libvirt] RFC: Detaching interface from guest fails with improper error message if no mac given in xml
This RFC is regarding https://bugzilla.redhat.com/show_bug.cgi?id=1497054 Let's say we have a network interface function='0x0'/> and we are trying to detach the above interface with the following xml(vfpool.xml): function='0x0'/> Detaching the interface returns error: # virsh detach-device vffuest vfpool.xml error: Failed to detach device from vfpool.xml error: operation failed: no device matching mac address 52:54:00:54:f6:61 found Here the mac address is auto-generated as we haven't given in the vfpool.xml. And virDomainNetFindIdx will try to match the auto-generated mac address with the domain xml. It fails as there will be no match and the error message says "no device matching mac address 52:54:00:54:f6:61 found". Here in this scenario I see two possible improvements. 1. As virDomainNetFindIdx search according to mac address and guest side PCI address (if specified), we can search for PCI address and avoid mac address search if mac is not given in the xml. As the PCI address is unique we don't compromise in performance. 2. Improve error message by saying mac address is missing in the device xml. -- libvir-list mailing list libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
