Message ID | 20230915113637.2127644-1-marcandre.lureau@redhat.com |
---|---|
State | New |
Headers | show |
Series | ui/gtk: fix UI info precondition | expand |
15.09.2023 14:36, marcandre.lureau@redhat.com: > From: Marc-André Lureau <marcandre.lureau@redhat.com> > > dpy_get_ui_info() shouldn't be called if the underlying GPU doesn't > support it. > > Before the assert() was added and the regression introduced, GTK code > used to get "zero" UI info, for ex with a simple VGA device. The assert > was added to prevent from calling when there are no console too. The > other display backend that calls dpy_get_ui_info() correctly checks that > pre-condition. > > Calling dpy_set_ui_info() is "safe" in this case, it will simply return > an error that can be generally ignored. > > Fixes: commit a92e7bb4c ("ui: add precondition for dpy_get_ui_info()") > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > --- > ui/gtk.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/ui/gtk.c b/ui/gtk.c > index e09f97a86b..7b542da0c0 100644 > --- a/ui/gtk.c > +++ b/ui/gtk.c > @@ -726,6 +726,10 @@ static void gd_set_ui_refresh_rate(VirtualConsole *vc, int refresh_rate) > { > QemuUIInfo info; > > + if (!dpy_ui_info_supported(vc->gfx.dcl.con)) { > + return; > + } > + > info = *dpy_get_ui_info(vc->gfx.dcl.con); Current dpy_ui_info_supported(): bool dpy_ui_info_supported(QemuConsole *con) { if (con == NULL) { con = active_console; } if (con == NULL) { return false; } return con->hw_ops->ui_info != NULL; } This whole thing smells a bit wrong. I'm not saying it *is* wrong, but the feeling is here. Where dpy_ui_info_supported() is called with a NULL con, so that an "active" console needs to be used instead? Maybe we should instead use something like if (!vc->gfx.dcl.con) here in gd_set_ui_refresh_rate() ? At the very least, the code is a bit, well, confusing. /mjt
Hi On Fri, Sep 15, 2023 at 4:46 PM Michael Tokarev <mjt@tls.msk.ru> wrote: > > 15.09.2023 14:36, marcandre.lureau@redhat.com: > > From: Marc-André Lureau <marcandre.lureau@redhat.com> > > > > dpy_get_ui_info() shouldn't be called if the underlying GPU doesn't > > support it. > > > > Before the assert() was added and the regression introduced, GTK code > > used to get "zero" UI info, for ex with a simple VGA device. The assert > > was added to prevent from calling when there are no console too. The > > other display backend that calls dpy_get_ui_info() correctly checks that > > pre-condition. > > > > Calling dpy_set_ui_info() is "safe" in this case, it will simply return > > an error that can be generally ignored. > > > > Fixes: commit a92e7bb4c ("ui: add precondition for dpy_get_ui_info()") > > Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com> > > --- > > ui/gtk.c | 8 ++++++++ > > 1 file changed, 8 insertions(+) > > > > diff --git a/ui/gtk.c b/ui/gtk.c > > index e09f97a86b..7b542da0c0 100644 > > --- a/ui/gtk.c > > +++ b/ui/gtk.c > > @@ -726,6 +726,10 @@ static void gd_set_ui_refresh_rate(VirtualConsole *vc, int refresh_rate) > > { > > QemuUIInfo info; > > > > + if (!dpy_ui_info_supported(vc->gfx.dcl.con)) { > > + return; > > + } > > + > > info = *dpy_get_ui_info(vc->gfx.dcl.con); > > Current dpy_ui_info_supported(): > > bool dpy_ui_info_supported(QemuConsole *con) > { > if (con == NULL) { > con = active_console; > } > if (con == NULL) { > return false; > } > > return con->hw_ops->ui_info != NULL; > } > > This whole thing smells a bit wrong. I'm not saying it *is* wrong, but > the feeling is here. > > Where dpy_ui_info_supported() is called with a NULL con, so that an "active" > console needs to be used instead? > > Maybe we should instead use something like > > if (!vc->gfx.dcl.con) > > here in gd_set_ui_refresh_rate() ? > > At the very least, the code is a bit, well, confusing. I agree it's a bit confusing to have dpy_*() functions accept NULL arguments to mean "active_console". I don't really have a good idea what to do else. Just having "if (!vc->gfx.dcl.con)" is not quite enough though, as we shouldn't get_ui_info() if it's not supported (there are no errors returned then, just "invalid/zero" values).
diff --git a/ui/gtk.c b/ui/gtk.c index e09f97a86b..7b542da0c0 100644 --- a/ui/gtk.c +++ b/ui/gtk.c @@ -726,6 +726,10 @@ static void gd_set_ui_refresh_rate(VirtualConsole *vc, int refresh_rate) { QemuUIInfo info; + if (!dpy_ui_info_supported(vc->gfx.dcl.con)) { + return; + } + info = *dpy_get_ui_info(vc->gfx.dcl.con); info.refresh_rate = refresh_rate; dpy_set_ui_info(vc->gfx.dcl.con, &info, true); @@ -735,6 +739,10 @@ static void gd_set_ui_size(VirtualConsole *vc, gint width, gint height) { QemuUIInfo info; + if (!dpy_ui_info_supported(vc->gfx.dcl.con)) { + return; + } + info = *dpy_get_ui_info(vc->gfx.dcl.con); info.width = width; info.height = height;