As pointed out by the Xen folks [1], HVM nics should always be set to type LIBXL_NIC_TYPE_VIF_IOEMU unless the user explicity requests LIBXL_NIC_TYPE_VIF via model='netfront'. The current logic in libxlMakeNic() only sets the nictype to LIBXL_NIC_TYPE_VIF_IOEMU if a model is specified that is not 'netfront', which breaks PXE booting configurations where no model is specified (i.e. use the hypervisor default). Reported-by: Stefan Bader <stefan.bader(a)canonical.com&gt; [1] https://www.redhat.com/archives/libvir-list/2013-December/msg01156.html Signed-off-by: Jim Fehlig <jfehlig(a)suse.com&gt; --- I toyed with detecting whether to use an IOEMU nic in libxlMakeNicList() and passing the bool to libxlMakeNic(), but in the end left the detection to libxlMakeNic(). src/libxl/libxl_conf.c | 20 ++++++++++++++------ src/libxl/libxl_conf.h | 4 +++- 2 files changed, 17 insertions(+), 7 deletions(-) diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index aaeb00e..04d01af 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -855,8 +855,12 @@ error: } int -libxlMakeNic(virDomainNetDefPtr l_nic, libxl_device_nic *x_nic) +libxlMakeNic(virDomainDefPtr def, + virDomainNetDefPtr l_nic, + libxl_device_nic *x_nic) { + bool ioemu_nic = STREQ(def->os.type, "hvm"); + /* TODO: Where is mtu stored? * * x_nics[i].mtu = 1492; @@ -866,12 +870,16 @@ libxlMakeNic(virDomainNetDefPtr l_nic, libxl_device_nic *x_nic) virMacAddrGetRaw(&l_nic->mac, x_nic->mac); - if (l_nic->model && !STREQ(l_nic->model, "netfront")) { - if (VIR_STRDUP(x_nic->model, l_nic->model) < 0) - return -1; + if (ioemu_nic) x_nic->nictype = LIBXL_NIC_TYPE_VIF_IOEMU; - } else { + else x_nic->nictype = LIBXL_NIC_TYPE_VIF; + + if (l_nic->model) { + if (VIR_STRDUP(x_nic->model, l_nic->model) < 0) + return -1; + if (STREQ(l_nic->model, "netfront")) + x_nic->nictype = LIBXL_NIC_TYPE_VIF; } if (VIR_STRDUP(x_nic->ifname, l_nic->ifname) < 0) @@ -908,7 +916,7 @@ libxlMakeNicList(virDomainDefPtr def, libxl_domain_config *d_config) return -1; for (i = 0; i < nnics; i++) { - if (libxlMakeNic(l_nics[i], &x_nics[i])) + if (libxlMakeNic(def, l_nics[i], &x_nics[i])) goto error; } diff --git a/src/libxl/libxl_conf.h b/src/libxl/libxl_conf.h index ffa93bd..90d590f 100644 --- a/src/libxl/libxl_conf.h +++ b/src/libxl/libxl_conf.h @@ -142,7 +142,9 @@ libxlMakeCapabilities(libxl_ctx *ctx); int libxlMakeDisk(virDomainDiskDefPtr l_dev, libxl_device_disk *x_dev); int -libxlMakeNic(virDomainNetDefPtr l_nic, libxl_device_nic *x_nic); +libxlMakeNic(virDomainDefPtr def, + virDomainNetDefPtr l_nic, + libxl_device_nic *x_nic); int libxlMakeVfb(libxlDriverPrivatePtr driver, virDomainGraphicsDefPtr l_vfb, libxl_device_vfb *x_vfb); -- 1.8.1.4