Re: [libvirt] [Spice-devel] [RFC PATCH] qemu: Use heads parameter for QXL driver

On Thu, Jun 11, 2015 at 12:39:50PM +0100, Frediano Ziglio wrote: Yes, this bit is worrying, the old behaviour could be considered as buggy as the XML contained '1' but the number of heads was not enforced. Suddenly enforcing the heads='1' (which libvirt will add by default to domain definitions which don't have it) will cause a change of behaviour for old guests though. Something like the patch below changes libvirt so that we don't always append heads='1' to domain XML, but I don't know if this interacts correctly with parallels and vmx which force it to be 1 (this probably should not be an issue, but maybe there are latent bugs). Also this is part of the things which are checked as part of virDomainVideoDefCheckABIStability() , so I suspect we'll need to be extra careful there too :( diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index 36de844..43067e9 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -11421,7 +11421,7 @@ virDomainVideoDefParseXML(xmlNodePtr node, goto error; } } else { - def->heads = 1; + def->heads = 0; } if (virDomainDeviceInfoParseXML(node, NULL, &def->info, flags) < 0) @@ -15507,7 +15507,6 @@ virDomainDefParseXML(xmlDocPtr xml, goto error; } video->vram = virDomainVideoDefaultRAM(def, video->type); - video->heads = 1; if (VIR_ALLOC_N(def->videos, 1) < 0) { virDomainVideoDefFree(video); goto error; diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 2bd63e1..03a0458 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -13411,7 +13411,6 @@ qemuParseCommandLine(virCapsPtr qemuCaps, vid->ram = 0; vid->vgamem = 0; } - vid->heads = 1; if (VIR_APPEND_ELEMENT(def->videos, def->nvideos, vid) < 0) { virDomainVideoDefFree(vid);