Reporting how much memory is exposed to the guest happens under <currentMemory/> which is taken from def->mem.cur_balloon. The reported amount should account for both balloon size and the sum of @actualsize of all virtio-mems. For instance, if domain has 4GiB via balloon and additional 2GiB via virtio-mem, then the domain XML should report 6GiB. The same applies for domain statistics.
The way to achieve this is to account for either balloon or virtio-mem when the size of the other is changed, e.g. on balloon change we have to add all @actualsize (for non virtio-mem these will be zero, so the check for memory model is needless, but makes it more obvious what's happening), and vice versa. Signed-off-by: Michal Privoznik <mpriv...@redhat.com> --- src/qemu/qemu_driver.c | 4 ++++ src/qemu/qemu_process.c | 17 +++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 6bcbc75fbc..d5891e32c3 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -4323,6 +4323,7 @@ processMemoryDeviceSizeChange(virQEMUDriverPtr driver, { virDomainMemoryDefPtr mem = NULL; virObjectEventPtr event = NULL; + unsigned long long balloon; if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0) return; @@ -4338,7 +4339,10 @@ processMemoryDeviceSizeChange(virQEMUDriverPtr driver, goto endjob; } + balloon = vm->def->mem.cur_balloon - mem->actualsize; mem->actualsize = VIR_DIV_UP(info->size, 1024); + balloon += mem->actualsize; + vm->def->mem.cur_balloon = balloon; event = virDomainEventMemoryDeviceSizeChangeNewFromObj(vm, info->devAlias, diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index dc301371ef..f6da5afb48 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -1253,10 +1253,19 @@ qemuProcessHandleBalloonChange(qemuMonitorPtr mon G_GNUC_UNUSED, virQEMUDriverPtr driver = opaque; virObjectEventPtr event = NULL; g_autoptr(virQEMUDriverConfig) cfg = virQEMUDriverGetConfig(driver); + size_t i; virObjectLock(vm); event = virDomainEventBalloonChangeNewFromObj(vm, actual); + /* We want the balloon size stored in domain definition to account for the + * actual size of virtio-mem too. */ + VIR_DEBUG("balloon size before fix is %lld", actual); + for (i = 0; i < vm->def->nmems; i++) { + if (vm->def->mems[i]->model == VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM) + actual += vm->def->mems[i]->actualsize; + } + VIR_DEBUG("Updating balloon from %lld to %lld kb", vm->def->mem.cur_balloon, actual); vm->def->mem.cur_balloon = actual; @@ -2451,6 +2460,7 @@ qemuProcessRefreshBalloonState(virQEMUDriverPtr driver, int asyncJob) { unsigned long long balloon; + size_t i; int rc; /* if no ballooning is available, the current size equals to the current @@ -2467,6 +2477,13 @@ qemuProcessRefreshBalloonState(virQEMUDriverPtr driver, if (qemuDomainObjExitMonitor(driver, vm) < 0 || rc < 0) return -1; + /* We want the balloon size stored in domain definition to account for the + * actual size of virtio-mem too. */ + VIR_DEBUG("balloon size before fix is %lld", balloon); + for (i = 0; i < vm->def->nmems; i++) { + if (vm->def->mems[i]->model == VIR_DOMAIN_MEMORY_MODEL_VIRTIO_MEM) + balloon += vm->def->mems[i]->actualsize; + } vm->def->mem.cur_balloon = balloon; return 0; -- 2.26.2