From: Marek Marczykowski-Górecki <marma...@invisiblethingslab.com> Device model stubdomains (both Mini-OS + qemu-trad and linux + qemu-xen) are always started with at least 3 consoles: log, save, and restore. Until xenconsoled learns how to handle multiple consoles, this is needed for save/restore support.
For Mini-OS stubdoms, this is a bug. In practice, it works in most cases because there is something else that triggers qemu in dom0 too: vfb/vkb added if vnc/sdl/spice is enabled. Additionally, Linux-based stubdomain waits for all the backends to initialize during boot. Lack of some console backends results in stubdomain startup timeout. This is a temporary patch until xenconsoled will be improved. Signed-off-by: Marek Marczykowski-Górecki <marma...@invisiblethingslab.com> [Updated commit message with Marek's explanation from mailing list.] Signed-off-by: Jason Andryuk <jandr...@gmail.com> Acked-by: Ian Jackson <ian.jack...@eu.citrix.com> --- Changes in v6 - Update commit message Changes in v7 - Add Acked-by: Ian Jackson --- tools/libxl/libxl_dm.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/tools/libxl/libxl_dm.c b/tools/libxl/libxl_dm.c index 6a26634ef9..8801e9364e 100644 --- a/tools/libxl/libxl_dm.c +++ b/tools/libxl/libxl_dm.c @@ -2494,7 +2494,11 @@ static void spawn_stub_launch_dm(libxl__egc *egc, } } - need_qemu = libxl__need_xenpv_qemu(gc, dm_config); + /* + * Until xenconsoled learns how to handle multiple consoles, require qemu + * in dom0 to serve consoles for a stubdomain - it require at least 3 of them. + */ + need_qemu = 1 || libxl__need_xenpv_qemu(gc, &sdss->dm_config); for (i = 0; i < num_console; i++) { libxl__device device; @@ -2626,7 +2630,11 @@ static void qmp_proxy_spawn_outcome(libxl__egc *egc, int rc) { STATE_AO_GC(sdss->qmp_proxy_spawn.ao); - int need_pvqemu = libxl__need_xenpv_qemu(gc, &sdss->dm_config); + /* + * Until xenconsoled learns how to handle multiple consoles, require qemu + * in dom0 to serve consoles for a stubdomain - it require at least 3 of them. + */ + int need_pvqemu = 1 || libxl__need_xenpv_qemu(gc, &sdss->dm_config); if (rc) goto out; -- 2.25.1