Hi Marc-André,
> Subject: Re: [PATCH] ui/gtk: Implement dpy_gl_ctx_destroy_texture for gtk-
> egl and gtk-gl-area
>
> Hi
>
> On Tue, Mar 3, 2026 at 4:13 AM <[email protected]> wrote:
> >
> > From: Dongwon Kim <[email protected]>
> >
> > Currently, the texture associated with a DisplaySurface is not deleted
> > when the surface is switched or freed, leading to a memory leak in the
> > GPU process. This occurs because the GTK backend lacks a mapping for
> > the 'dpy_gl_ctx_destroy_texture' operation.
> >
> > This patch implements the necessary cleanup functions for both EGL and
> > GL Area backends. Each implementation ensures the appropriate GL
> > context is made current before calling surface_gl_destroy_texture(),
> > ensuring that the underlying GL texture ID is safely released by the driver.
> >
> > Cc: Gerd Hoffmann <[email protected]>
> > Cc: Marc-André Lureau <[email protected]>
> > Cc: Vivek Kasireddy <[email protected]>
> > Signed-off-by: Dongwon Kim <[email protected]>
> > ---
> > include/ui/gtk.h | 4 ++++
> > ui/gtk-egl.c | 10 ++++++++++
> > ui/gtk-gl-area.c | 8 ++++++++
> > ui/gtk.c | 2 ++
> > 4 files changed, 24 insertions(+)
> >
> > diff --git a/include/ui/gtk.h b/include/ui/gtk.h index
> > 3e6ce3cb48..f1765ad5cb 100644
> > --- a/include/ui/gtk.h
> > +++ b/include/ui/gtk.h
> > @@ -170,6 +170,8 @@ void gd_egl_switch(DisplayChangeListener *dcl,
> > DisplaySurface *surface); QEMUGLContext
> > gd_egl_create_context(DisplayGLCtx *dgc,
> > QEMUGLParams *params);
> > +void gd_egl_destroy_texture(DisplayGLCtx *dgc,
> > + DisplaySurface *surface);
> > void gd_egl_scanout_disable(DisplayChangeListener *dcl); void
> > gd_egl_scanout_texture(DisplayChangeListener *dcl,
> > uint32_t backing_id, @@ -206,6 +208,8 @@
> > QEMUGLContext gd_gl_area_create_context(DisplayGLCtx *dgc,
> > QEMUGLParams *params); void
> > gd_gl_area_destroy_context(DisplayGLCtx *dgc,
> > QEMUGLContext ctx);
> > +void gd_gl_area_destroy_texture(DisplayGLCtx *dgc,
> > + DisplaySurface *surface);
> > void gd_gl_area_scanout_dmabuf(DisplayChangeListener *dcl,
> > QemuDmaBuf *dmabuf); void
> > gd_gl_area_scanout_texture(DisplayChangeListener *dcl, diff --git
> > a/ui/gtk-egl.c b/ui/gtk-egl.c index ae9239999c..c1b32bc41b 100644
> > --- a/ui/gtk-egl.c
> > +++ b/ui/gtk-egl.c
> > @@ -225,6 +225,16 @@ QEMUGLContext
> gd_egl_create_context(DisplayGLCtx *dgc,
> > return qemu_egl_create_context(dgc, params); }
> >
> > +void gd_egl_destroy_texture(DisplayGLCtx *dgc, DisplaySurface
> > +*surface) {
> > + VirtualConsole *vc = container_of(dgc, VirtualConsole, gfx.dgc);
> > +
> > + eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
> > + vc->gfx.esurface, vc->gfx.ectx);
> > +
> > + surface_gl_destroy_texture(dgc->gls, surface); }
> > +
> > void gd_egl_scanout_disable(DisplayChangeListener *dcl) {
> > VirtualConsole *vc = container_of(dcl, VirtualConsole, gfx.dcl);
> > diff --git a/ui/gtk-gl-area.c b/ui/gtk-gl-area.c index
> > cd86022d26..84e41f4221 100644
> > --- a/ui/gtk-gl-area.c
> > +++ b/ui/gtk-gl-area.c
> > @@ -299,6 +299,14 @@ void gd_gl_area_destroy_context(DisplayGLCtx
> *dgc, QEMUGLContext ctx)
> > g_clear_object(&ctx);
> > }
> >
> > +void gd_gl_area_destroy_texture(DisplayGLCtx *dgc, DisplaySurface
> > +*surface) {
> > + VirtualConsole *vc = container_of(dgc, VirtualConsole, gfx.dgc);
> > +
> > + gtk_gl_area_make_current(GTK_GL_AREA(vc->gfx.drawing_area));
> > + surface_gl_destroy_texture(dgc->gls, surface); }
> > +
> > void gd_gl_area_scanout_texture(DisplayChangeListener *dcl,
> > uint32_t backing_id,
> > bool backing_y_0_top, diff --git
> > a/ui/gtk.c b/ui/gtk.c index 9ebe7e8df0..217f425075 100644
> > --- a/ui/gtk.c
> > +++ b/ui/gtk.c
> > @@ -636,6 +636,7 @@ static const DisplayGLCtxOps gl_area_ctx_ops = {
> > .dpy_gl_ctx_is_compatible_dcl = gd_gl_area_is_compatible_dcl,
> > .dpy_gl_ctx_create = gd_gl_area_create_context,
> > .dpy_gl_ctx_destroy = gd_gl_area_destroy_context,
> > + .dpy_gl_ctx_destroy_texture = gd_gl_area_destroy_texture,
> > .dpy_gl_ctx_make_current = gd_gl_area_make_current, };
> >
> > @@ -670,6 +671,7 @@ static const DisplayGLCtxOps egl_ctx_ops = {
> > .dpy_gl_ctx_is_compatible_dcl = gd_egl_is_compatible_dcl,
> > .dpy_gl_ctx_create = gd_egl_create_context,
> > .dpy_gl_ctx_destroy = qemu_egl_destroy_context,
> > + .dpy_gl_ctx_destroy_texture = gd_egl_destroy_texture,
> > .dpy_gl_ctx_make_current = gd_egl_make_current,
>
> But there is no dpy_gl_ctx_create_texture(), how can
> dpy_gl_ctx_destroy_texture() get called?
Textures are also created via surface_gl_create_texture in the places like,
gtk-egl.c
static void gtk_egl_set_scanout_mode(VirtualConsole *vc, bool scanout)
{
.....
egl_fb_destroy(&vc->gfx.guest_fb);
if (vc->gfx.surface) {
surface_gl_destroy_texture(vc->gfx.gls, vc->gfx.ds);
surface_gl_create_texture(vc->gfx.gls, vc->gfx.ds);
}
surface_gl_create_texture always come after surface_gl_destroy_texture
so there is no leak while the guest is running but texture would remain
unremoved
if we do none in dpy_gl_ctx_destroy_texture() when the guest is rebooting.
>
> > };
> > #endif
> > --
> > 2.43.0
> >
> >
>
>
> --
> Marc-André Lureau
Thanks
