Commit b7798a07f93 (in fall of 2016) changed the way we generate aliases for 'dimm' memory devices as the alias itself is part of the migration stream section naming and thus must be treated as ABI.
The code added compatibility layer for VMs with memory hotplug started with the old scheme to prevent from generating wrong aliases. The compatibility layer broke though later when 'nvdimm' and 'pmem' devices were introduced as it wrongly detected them as old configuration. Now rather than attempting to fix the legacy compat layer to treat other devices properly we'll be better off simply removing it as it's extremely unlikely that somebody has a VM started in 2016 running with today's libvirt and attempts to hotplug more memory. This fixes a corner case when a user hot-adds a 'dimm' into a VM with a 'dimm' and a 'nvdimm' after restart of libvirtd and then attempts to migrate the VM. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2158701 Signed-off-by: Peter Krempa <pkre...@redhat.com> --- src/qemu/qemu_hotplug.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c index 026e1ee5ad..5840504d13 100644 --- a/src/qemu/qemu_hotplug.c +++ b/src/qemu/qemu_hotplug.c @@ -2275,9 +2275,7 @@ qemuDomainAttachMemory(virQEMUDriver *driver, goto cleanup; releaseaddr = true; - /* in cases where we are using a VM with aliases generated according to the - * index of the memory device we need to keep continue using that scheme */ - if (qemuAssignDeviceMemoryAlias(vm->def, mem, priv->memAliasOrderMismatch) < 0) + if (qemuAssignDeviceMemoryAlias(vm->def, mem, false) < 0) goto cleanup; objalias = g_strdup_printf("mem%s", mem->info.alias); -- 2.38.1
