On 07/09/2018 10:32 AM, Michal Privoznik wrote:
On 07/06/2018 08:50 PM, John Ferlan wrote:
Prior to the hostdev being inserted in the hostdevs list, add a check during qemuDomainAttachDeviceConfig to determine whether the new/incoming <hostdev ...> device is providing the same <address> as some existing hostdev on the list and if so fail the cold attach.
This cannot be done during virDomainHostdevDefPostParse because that is called after virDomainDefParseXML would have inserted a hostdev onto the hostdevs list and thus would have a "conflict" with itself. Therefore, the post parse processing can only compare if the current hostdev address conflicts with a SCSI <disk> address.
By comparison this is similar to the validation phase checks in virDomainDefCheckDuplicateDriveAddresses that occur during define/startup processing but are not run during config attach of a live guest.
Signed-off-by: John Ferlan <jferlan@redhat.com> --- src/qemu/qemu_driver.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 9a35e04a85..ef1abe3f68 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -8007,6 +8007,12 @@ qemuDomainAttachDeviceConfig(virDomainDefPtr vmdef, _("device is already in the domain configuration")); return -1; } + if (dev->data.hostdev->info->type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE && + virDomainDefHasDeviceAddress(vmdef, dev->data.hostdev->info)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("a device with the same address already exists ")); + return -1; + } if (virDomainHostdevInsert(vmdef, hostdev)) return -1; dev->data.hostdev = NULL;
I think hostdevs are not the only type of device suffering from this. In fact, I've just tested disks and libvirt accepts attaching another disk onto same <address/> happily.
I wonder if this should go into virDomainDefCompatibleDevice() (now that we have @action there ;-) ).
It's a case of myopia for the bug I'm working on as listed in patch2. What I did is no different than the VIR_DOMAIN_DEVICE_RNG check in the same function. Still, if I change this patch to add: if (action == VIR_DOMAIN_DEVICE_ACTION_ATTACH && !live && data.newInfo && data.newInfo->type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE && virDomainDefHasDeviceAddress(def, data.newInfo)) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", _("a device with the same address already exists ")); return -1; } to virDomainDefCompatibleDevice and remove the (new)hostdev and (existing)rng checks, then I believe it covers the existing cases. Tks - John