On 28.02.2018 12:02, David Hildenbrand wrote: > On 27.02.2018 12:32, Thomas Huth wrote: >> The file name of the netboot binary is currently hard-coded to >> "s390-netboot.img", without a possibility for the user to select >> an alternative firmware image here. That's unfortunate, especially >> since the basics are already there: The filename is a property of >> the s390-ipl device. So we just have to add a check whether the user >> already provided the property and only set the default if the string >> is still empty. Now it is possible to select a different firmware >> image with "-global s390-ipl.netboot_fw=/path/to/s390-netboot.img". >> >> Signed-off-by: Thomas Huth <th...@redhat.com> >> --- >> hw/s390x/s390-virtio-ccw.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c >> index 4abbe89..7b3fb5f 100644 >> --- a/hw/s390x/s390-virtio-ccw.c >> +++ b/hw/s390x/s390-virtio-ccw.c >> @@ -254,8 +254,10 @@ static void s390_init_ipl_dev(const char >> *kernel_filename, >> } >> qdev_prop_set_string(dev, "cmdline", kernel_cmdline); >> qdev_prop_set_string(dev, "firmware", firmware); >> - qdev_prop_set_string(dev, "netboot_fw", netboot_fw); >> qdev_prop_set_bit(dev, "enforce_bios", enforce_bios); >> + if (!strlen(object_property_get_str(new, "netboot_fw", &error_abort))) { > > Isn't it the case that object_property_get_str() can return also NULL? > > (looking at s390_ipl_set_loadparm())
It can return NULL in case of errors (e.g. the property is not a string or not available at all). In this case, we know that the property is a string and that it is available, so IMHO no need to check for NULL here. Not sure why s390_ipl_set_loadparm() explicitely checks for this ... maybe this was originally required to support the old s390-virtio (non-ccw) machine, too? Thomas