Re: [libvirt] [PATCH 02/12] qemu: command: spice: Pick the first available DRM render node

Up until now, we formatted 'rendernode=' onto QEMU cmdline only if the user specified it in the XML, otherwise we let QEMU do it for us. This causes permission issues because by default the /dev/dri/renderDX permissions are as follows: crw-rw----. 1 root video There's literally no reason why it shouldn't be libvirt picking the DRM render node instead of QEMU, that way (and because we're using namespaces by default), we can safely relabel the device within the namespace. Signed-off-by: Erik Skultety <eskultet(a)redhat.com&gt; --- src/qemu/qemu_command.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 23a6661c10..f6bee10d5c 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -8235,6 +8235,8 @@ qemuBuildGraphicsSPICECommandLine(virQEMUDriverConfigPtr cfg, } if (graphics->data.spice.gl == VIR_TRISTATE_BOOL_YES) { + char **rendernode = &graphics->data.spice.rendernode; + if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_SPICE_GL)) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", _("This QEMU doesn't support spice OpenGL")); @@ -8246,17 +8248,20 @@ qemuBuildGraphicsSPICECommandLine(virQEMUDriverConfigPtr cfg, virBufferAsprintf(&opt, "gl=%s,", virTristateSwitchTypeToString(graphics->data.spice.gl)); - if (graphics->data.spice.rendernode) { - if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_SPICE_RENDERNODE)) { - virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", - _("This QEMU doesn't support spice OpenGL rendernode")); - goto error; - } - - virBufferAddLit(&opt, "rendernode="); - virQEMUBuildBufferEscapeComma(&opt, graphics->data.spice.rendernode); - virBufferAddLit(&opt, ","); + if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_SPICE_RENDERNODE)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("This QEMU doesn't support spice OpenGL rendernode")); + goto error; } + + /* pick the first DRM render node if none was specified */ + if (!*rendernode && + !(*rendernode = virHostGetDRMRenderNode()))