Re: [libvirt] [PATCH 1/2] util:mdev: Improve the error msg on non-existent mdev prior to VM start

missing space in summary On Fri, Mar 16, 2018 at 11:50:01 +0100, Erik Skultety wrote: > What one currently gets is: > failed to read '/sys/bus/mdev/devices/<UUID>/mdev_type/device_api': No > such file or directory > > This indicates that something is missing within the device's sysfs tree > which likely might be not be the case here because the device simply > doesn't exist yet. So, when creating our internal mdev obj, let's check > whether the device exists first prior to trying to verify the > user-provided model within domain XML. > > Signed-off-by: Erik Skultety <eskultet(a)redhat.com&gt; > --- > src/util/virmdev.c | 16 +++++++++++++--- > 1 file changed, 13 insertions(+), 3 deletions(-) > > diff --git a/src/util/virmdev.c b/src/util/virmdev.c > index e4816cf20..2e3769aa6 100644 > --- a/src/util/virmdev.c > +++ b/src/util/virmdev.c > @@ -150,13 +150,22 @@ virMediatedDeviceNew(const char *uuidstr, virMediatedDeviceModelType model) > { > virMediatedDevicePtr ret = NULL; > virMediatedDevicePtr dev = NULL; > + char *sysfspath = NULL; > + > + if (!(sysfspath = virMediatedDeviceGetSysfsPath(uuidstr))) > + goto cleanup; > + > + if (!virFileExists(sysfspath)) { > + virReportSystemError(errno, _("failed to read device '%s'"), > + sysfspath); You did not try to read the device at this point. It merely does not exist.