From d34640b0c0ec45ac59f508b0d616518740ee5d90 Mon Sep 17 00:00:00 2001 From: Lei Yang Date: Mon, 30 Aug 2021 16:02:50 +0800 Subject: [PATCH] qemu: fix iothread residual when qemuProcessSetupIOThread failed In process of iothread hotplug, qemuDomainHotplugAddIOThread() calls qemuProcessSetupIOThread(). When qemuProcessSetupIOThread() returned a failure, only the cgroup directory 'iothread' was cleaned up within the function. Right after that qemuDomainHotplugAddIOThread() would return failure directly without rolling back the livedef and iothread process that created previously. Further, when 'virsh schedinfo domain --live' requires schedinfo of such machine, the interface will always return a failure print as follows: 'Failed to create v1 controller cpu for group: No such file or directory'. The reason is qemuGetIOThreadsBWLive() using member vm->def->iothreadids[0]->iothread_id to findout the corresponding cgroup dircetory. In case mentioned previously, iothreadids[0] was not been cleaned up while whose cgroup directroy has already been removed. This patch rolls back the livedef and iothread process after qemuProcessSetupIOThread() returned a failure. Of course we are not limited to this function, we also perform the same rolling back after any exception proecss in qemuDomainHotplugAddIOThread(). Signed-off-by: Lei Yang Signed-off-by: Wang Xin Signed-off-by: Michal Privoznik Reviewed-by: Michal Privoznik --- src/qemu/qemu_driver.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) mode change 100644 => 100755 src/qemu/qemu_driver.c diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c old mode 100644 new mode 100755 index f1f961c51c..cbd48b1849 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -5293,6 +5293,8 @@ qemuDomainHotplugAddIOThread(virQEMUDriver *driver, qemuMonitorIOThreadInfo **new_iothreads = NULL; virDomainIOThreadIDDef *iothrid; virJSONValue *props = NULL; + bool threadAdded = false; + bool objectAdded = false; if (!(alias = g_strdup_printf("iothread%u", iothread_id))) return -1; @@ -5305,6 +5307,8 @@ qemuDomainHotplugAddIOThread(virQEMUDriver *driver, if (qemuMonitorAddObject(priv->mon, &props, NULL) < 0) goto exit_monitor; + objectAdded = true; + exp_niothreads++; /* After hotplugging the IOThreads we need to re-detect the @@ -5344,6 +5348,7 @@ qemuDomainHotplugAddIOThread(virQEMUDriver *driver, if (!(iothrid = virDomainIOThreadIDAdd(vm->def, iothread_id))) goto cleanup; + threadAdded = true; iothrid->thread_id = new_iothreads[idx]->thread_id; if (qemuProcessSetupIOThread(vm, iothrid) < 0) @@ -5352,6 +5357,19 @@ qemuDomainHotplugAddIOThread(virQEMUDriver *driver, ret = 0; cleanup: + if (ret < 0) { + if (threadAdded) + virDomainIOThreadIDDel(vm->def, iothread_id); + + if (objectAdded) { + qemuDomainObjEnterMonitor(driver, vm); + if (qemuMonitorDelObject(priv->mon, alias, true) < 0) + VIR_WARN("deletion of iothread object %d of domain %s failed when cleanup", + iothread_id, vm->def->name); + ignore_value(qemuDomainObjExitMonitor(driver, vm)); + } + } + if (new_iothreads) { for (idx = 0; idx < new_niothreads; idx++) VIR_FREE(new_iothreads[idx]);