Re: [libvirt] [PATCH 11/12] qemu: Implement random number generator hotplug

On Fri, Feb 06, 2015 at 04:32:25PM +0100, Peter Krempa wrote: > From: Luyao Huang <lhuang(a)redhat.com&gt; > > Export the required helpers and add backend code to hotplug RNG devices. > > Signed-off-by: Luyao Huang <lhuang(a)redhat.com&gt; > Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; > --- > src/qemu/qemu_command.c | 2 +- > src/qemu/qemu_command.h | 4 ++ > src/qemu/qemu_driver.c | 8 +++- > src/qemu/qemu_hotplug.c | 99 +++++++++++++++++++++++++++++++++++++++++++++++++ > src/qemu/qemu_hotplug.h | 3 ++ > 5 files changed, 114 insertions(+), 2 deletions(-) > -- 8< 8< 8< -- > + > + /* attach the device - up to a 3 stage process */ > + qemuDomainObjEnterMonitor(driver, vm); > + > + if (rng->backend == VIR_DOMAIN_RNG_BACKEND_EGD && > + qemuMonitorAttachCharDev(priv->mon, charAlias, > + rng->source.chardev) < 0) > + goto failchardev; > + > + if (qemuMonitorAddObject(priv->mon, type, objAlias, props) < 0) > + goto failbackend; > + > + if (qemuMonitorAddDevice(priv->mon, devstr) < 0) > + goto failfrontend; > + > + if (qemuDomainObjExitMonitor(driver, vm) < 0) { > + vm = NULL; > + goto cleanup; > + } I know an OOM error at this exact location is not that likely, but it would be nicer to prealloc the space in vm->def before entering the monitor so that the operation below cannot fail, like we do when hotplugging other devices.

Jan