Marc-André Lureau <marcandre.lur...@gmail.com> writes: > Hi > > On Tue, Jul 31, 2018 at 1:30 PM, Markus Armbruster <arm...@redhat.com> wrote: >> Marc-André Lureau <marcandre.lur...@redhat.com> writes: >> >>> A chardev may stop trying to write if the associated can_read() >>> callback returned 0. This happens when the monitor is suspended. >>> The frontend is supposed to call qemu_chr_fe_accept_input() when it is >>> ready to accept data again. >>> >>> Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com> >> >> Impact? > > I have observed the issue with a spice port, all pending commands > aren't flushed. Most chardev don't use the accept_input() callback, > and instead poll regularly, like char-socket.c:tcp_chr_read_poll()
The ones that do use it are braille, mux, msmouse, spice (abstract), spicevmc, spiceport, wctablet. A description of the impact should be worked into the commit message. >> Is this to be considered for 3.0? > > This is not a regression, afaik, and doesn't impact common monitor > chardev. So it could be delayed. But it's also a small fix for Spice > chardev that shouldn't create regression, so it should be fine for > 3.0. If the callbacks we now call all work fine, we should be good. But that's a chardev question, and I'm the guy for the monitor questions. I think the decision needs to be made by maintainers of the chardev subsystem. Preferably with an improved commit message: Acked-by: Markus Armbruster <arm...@redhat.com>