On Fri, Jan 22, 2021 at 01:49:38PM +0100, Laszlo Ersek wrote: > On 01/22/21 09:46, Gerd Hoffmann wrote: > >> This patch breaks QEMU for me. > > > >> The symptom is the following: in virt-manager, the display remains dead > >> (black), when I start an OVMF guest. At the same time, unusually high > >> CPU load can be seen on the host; it makes me think that virt-manager is > >> trying, in a busy loop, to complete the VNC handshake, or some such. > >> Ultimately, although the guest boots up fine, virt-manager gives up, and > >> the display window says "Viewer was disconnected". > > > > It is the vnc_colordepth() call. Seems gtk-vnc sends a update request > > with incremental=0 as response to the VNC_ENCODING_WMVi message. So > > sending that as response to an incremental=0 update request creates an > > endless loop ... > > Interesting; I saw that commit 9e1632ad07ca *added* (as opposed to > *moving*) the vnc_colordepth() call; I thought it was a relatively > insignificant bit...
/me too. Some discussions in the resize changes indicated that the idea of a non-incremetal update request is that the server sends the *full* server-side state, so the client can render the screen properly without remembering old state. So I thought ok, lets send the colordepth info too, no big deal ... take care, Gerd