Don't change bound GL context when creating new GL context for consistency
with behavior expected by virglrenderer that assumes context-creation doesn't
switch context. eglCreateContext() doesn't require GL context to be bound
when it's invoked. Update qemu_egl_create_context() to spawn GL sub-contexts
from a common parent GL context instead of a currently-bound context.
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
---
ui/dbus.c | 2 --
ui/egl-context.c | 3 +--
ui/egl-headless.c | 2 --
ui/gtk-egl.c | 4 ----
ui/spice-display.c | 2 --
5 files changed, 1 insertion(+), 12 deletions(-)
diff --git a/ui/dbus.c b/ui/dbus.c
index 905ee6fea71b..750a064e3fbf 100644
--- a/ui/dbus.c
+++ b/ui/dbus.c
@@ -47,8 +47,6 @@ static DBusDisplay *dbus_display;
static QEMUGLContext dbus_create_context(DisplayGLCtx *dgc,
QEMUGLParams *params)
{
- eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
- qemu_egl_rn_ctx);
return qemu_egl_create_context(dgc, params);
}
diff --git a/ui/egl-context.c b/ui/egl-context.c
index aed3e3ba1f3f..f9a998768beb 100644
--- a/ui/egl-context.c
+++ b/ui/egl-context.c
@@ -19,8 +19,7 @@ QEMUGLContext qemu_egl_create_context(DisplayGLCtx *dgc,
};
bool gles = (qemu_egl_mode == DISPLAY_GL_MODE_ES);
- ctx = eglCreateContext(qemu_egl_display, qemu_egl_config,
- eglGetCurrentContext(),
+ ctx = eglCreateContext(qemu_egl_display, qemu_egl_config, qemu_egl_rn_ctx,
gles ? ctx_att_gles : ctx_att_core);
return ctx;
}
diff --git a/ui/egl-headless.c b/ui/egl-headless.c
index 1f6b845500dd..19955792ac95 100644
--- a/ui/egl-headless.c
+++ b/ui/egl-headless.c
@@ -42,8 +42,6 @@ static void egl_gfx_switch(DisplayChangeListener *dcl,
static QEMUGLContext egl_create_context(DisplayGLCtx *dgc,
QEMUGLParams *params)
{
- eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
- qemu_egl_rn_ctx);
return qemu_egl_create_context(dgc, params);
}
diff --git a/ui/gtk-egl.c b/ui/gtk-egl.c
index 0dbb429958e5..6b3519419039 100644
--- a/ui/gtk-egl.c
+++ b/ui/gtk-egl.c
@@ -217,10 +217,6 @@ void gd_egl_switch(DisplayChangeListener *dcl,
QEMUGLContext gd_egl_create_context(DisplayGLCtx *dgc,
QEMUGLParams *params)
{
- VirtualConsole *vc = container_of(dgc, VirtualConsole, gfx.dgc);
-
- eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
- vc->gfx.esurface, vc->gfx.ectx);
return qemu_egl_create_context(dgc, params);
}
diff --git a/ui/spice-display.c b/ui/spice-display.c
index 28399f8a8174..ae0f771c2a38 100644
--- a/ui/spice-display.c
+++ b/ui/spice-display.c
@@ -1033,8 +1033,6 @@ static void spice_gl_switch(DisplayChangeListener *dcl,
static QEMUGLContext qemu_spice_gl_create_context(DisplayGLCtx *dgc,
QEMUGLParams *params)
{
- eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
- qemu_egl_rn_ctx);
return qemu_egl_create_context(dgc, params);
}
--
2.52.0On 2026/03/02 23:59, Dmitry Osipenko wrote:
> Don't change bound GL context when creating new GL context for consistency
> with behavior expected by virglrenderer that assumes context-creation doesn't
> switch context. eglCreateContext() doesn't require GL context to be bound
> when it's invoked. Update qemu_egl_create_context() to spawn GL sub-contexts
> from a common parent GL context instead of a currently-bound context.
>
> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
> ---
> ui/dbus.c | 2 --
> ui/egl-context.c | 3 +--
> ui/egl-headless.c | 2 --
> ui/gtk-egl.c | 4 ----
> ui/spice-display.c | 2 --
> 5 files changed, 1 insertion(+), 12 deletions(-)
>
> diff --git a/ui/dbus.c b/ui/dbus.c
> index 905ee6fea71b..750a064e3fbf 100644
> --- a/ui/dbus.c
> +++ b/ui/dbus.c
> @@ -47,8 +47,6 @@ static DBusDisplay *dbus_display;
> static QEMUGLContext dbus_create_context(DisplayGLCtx *dgc,
> QEMUGLParams *params)
> {
> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
> - qemu_egl_rn_ctx);
> return qemu_egl_create_context(dgc, params);
> }
>
> diff --git a/ui/egl-context.c b/ui/egl-context.c
> index aed3e3ba1f3f..f9a998768beb 100644
> --- a/ui/egl-context.c
> +++ b/ui/egl-context.c
> @@ -19,8 +19,7 @@ QEMUGLContext qemu_egl_create_context(DisplayGLCtx *dgc,
> };
> bool gles = (qemu_egl_mode == DISPLAY_GL_MODE_ES);
>
> - ctx = eglCreateContext(qemu_egl_display, qemu_egl_config,
> - eglGetCurrentContext(),
> + ctx = eglCreateContext(qemu_egl_display, qemu_egl_config, qemu_egl_rn_ctx,
> gles ? ctx_att_gles : ctx_att_core);
> return ctx;
> }
> diff --git a/ui/egl-headless.c b/ui/egl-headless.c
> index 1f6b845500dd..19955792ac95 100644
> --- a/ui/egl-headless.c
> +++ b/ui/egl-headless.c
> @@ -42,8 +42,6 @@ static void egl_gfx_switch(DisplayChangeListener *dcl,
> static QEMUGLContext egl_create_context(DisplayGLCtx *dgc,
> QEMUGLParams *params)
> {
> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
> - qemu_egl_rn_ctx);
> return qemu_egl_create_context(dgc, params);
> }
>
> diff --git a/ui/gtk-egl.c b/ui/gtk-egl.c
> index 0dbb429958e5..6b3519419039 100644
> --- a/ui/gtk-egl.c
> +++ b/ui/gtk-egl.c
> @@ -217,10 +217,6 @@ void gd_egl_switch(DisplayChangeListener *dcl,
> QEMUGLContext gd_egl_create_context(DisplayGLCtx *dgc,
> QEMUGLParams *params)
> {
> - VirtualConsole *vc = container_of(dgc, VirtualConsole, gfx.dgc);
> -
> - eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
> - vc->gfx.esurface, vc->gfx.ectx);
This uses vc->gfx.ectx instead of qemu_egl_rn_ctx so it should be passed
to qemu_egl_create_context().
Regards,
Akihiko Odaki
> return qemu_egl_create_context(dgc, params);
> }
>
> diff --git a/ui/spice-display.c b/ui/spice-display.c
> index 28399f8a8174..ae0f771c2a38 100644
> --- a/ui/spice-display.c
> +++ b/ui/spice-display.c
> @@ -1033,8 +1033,6 @@ static void spice_gl_switch(DisplayChangeListener *dcl,
> static QEMUGLContext qemu_spice_gl_create_context(DisplayGLCtx *dgc,
> QEMUGLParams *params)
> {
> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
> - qemu_egl_rn_ctx);
> return qemu_egl_create_context(dgc, params);
> }
>
On 3/3/26 06:49, Akihiko Odaki wrote:
> On 2026/03/02 23:59, Dmitry Osipenko wrote:
>> Don't change bound GL context when creating new GL context for
>> consistency
>> with behavior expected by virglrenderer that assumes context-creation
>> doesn't
>> switch context. eglCreateContext() doesn't require GL context to be bound
>> when it's invoked. Update qemu_egl_create_context() to spawn GL sub-
>> contexts
>> from a common parent GL context instead of a currently-bound context.
>>
>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
>> ---
>> ui/dbus.c | 2 --
>> ui/egl-context.c | 3 +--
>> ui/egl-headless.c | 2 --
>> ui/gtk-egl.c | 4 ----
>> ui/spice-display.c | 2 --
>> 5 files changed, 1 insertion(+), 12 deletions(-)
>>
>> diff --git a/ui/dbus.c b/ui/dbus.c
>> index 905ee6fea71b..750a064e3fbf 100644
>> --- a/ui/dbus.c
>> +++ b/ui/dbus.c
>> @@ -47,8 +47,6 @@ static DBusDisplay *dbus_display;
>> static QEMUGLContext dbus_create_context(DisplayGLCtx *dgc,
>> QEMUGLParams *params)
>> {
>> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
>> - qemu_egl_rn_ctx);
>> return qemu_egl_create_context(dgc, params);
>> }
>> diff --git a/ui/egl-context.c b/ui/egl-context.c
>> index aed3e3ba1f3f..f9a998768beb 100644
>> --- a/ui/egl-context.c
>> +++ b/ui/egl-context.c
>> @@ -19,8 +19,7 @@ QEMUGLContext qemu_egl_create_context(DisplayGLCtx
>> *dgc,
>> };
>> bool gles = (qemu_egl_mode == DISPLAY_GL_MODE_ES);
>> - ctx = eglCreateContext(qemu_egl_display, qemu_egl_config,
>> - eglGetCurrentContext(),
>> + ctx = eglCreateContext(qemu_egl_display, qemu_egl_config,
>> qemu_egl_rn_ctx,
>> gles ? ctx_att_gles : ctx_att_core);
>> return ctx;
>> }
>> diff --git a/ui/egl-headless.c b/ui/egl-headless.c
>> index 1f6b845500dd..19955792ac95 100644
>> --- a/ui/egl-headless.c
>> +++ b/ui/egl-headless.c
>> @@ -42,8 +42,6 @@ static void egl_gfx_switch(DisplayChangeListener *dcl,
>> static QEMUGLContext egl_create_context(DisplayGLCtx *dgc,
>> QEMUGLParams *params)
>> {
>> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
>> - qemu_egl_rn_ctx);
>> return qemu_egl_create_context(dgc, params);
>> }
>> diff --git a/ui/gtk-egl.c b/ui/gtk-egl.c
>> index 0dbb429958e5..6b3519419039 100644
>> --- a/ui/gtk-egl.c
>> +++ b/ui/gtk-egl.c
>> @@ -217,10 +217,6 @@ void gd_egl_switch(DisplayChangeListener *dcl,
>> QEMUGLContext gd_egl_create_context(DisplayGLCtx *dgc,
>> QEMUGLParams *params)
>> {
>> - VirtualConsole *vc = container_of(dgc, VirtualConsole, gfx.dgc);
>> -
>> - eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
>> - vc->gfx.esurface, vc->gfx.ectx);
>
> This uses vc->gfx.ectx instead of qemu_egl_rn_ctx so it should be passed
> to qemu_egl_create_context().
Good catch. AFAICS, the vc->gfx.ectx is initialized only once in the
code. Will double check.
One problem with gtk-egl display is that this is the only display type I
haven't tested because it's not obvious how to do it, The gdk-area is
what always get used on my machine with both x11 and wayland, and
forcing gtk-egl in the code instead of gdk-area results in a crash. I'd
appreciate if anyone could clarify how to make QEMU use gtk-egl or
whether it has been obsoleted and doesn't work with modern GTK.
--
Best regards,
Dmitry
On 2026/03/03 21:05, Dmitry Osipenko wrote:
> On 3/3/26 06:49, Akihiko Odaki wrote:
>> On 2026/03/02 23:59, Dmitry Osipenko wrote:
>>> Don't change bound GL context when creating new GL context for
>>> consistency
>>> with behavior expected by virglrenderer that assumes context-creation
>>> doesn't
>>> switch context. eglCreateContext() doesn't require GL context to be bound
>>> when it's invoked. Update qemu_egl_create_context() to spawn GL sub-
>>> contexts
>>> from a common parent GL context instead of a currently-bound context.
>>>
>>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
>>> ---
>>> ui/dbus.c | 2 --
>>> ui/egl-context.c | 3 +--
>>> ui/egl-headless.c | 2 --
>>> ui/gtk-egl.c | 4 ----
>>> ui/spice-display.c | 2 --
>>> 5 files changed, 1 insertion(+), 12 deletions(-)
>>>
>>> diff --git a/ui/dbus.c b/ui/dbus.c
>>> index 905ee6fea71b..750a064e3fbf 100644
>>> --- a/ui/dbus.c
>>> +++ b/ui/dbus.c
>>> @@ -47,8 +47,6 @@ static DBusDisplay *dbus_display;
>>> static QEMUGLContext dbus_create_context(DisplayGLCtx *dgc,
>>> QEMUGLParams *params)
>>> {
>>> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
>>> - qemu_egl_rn_ctx);
>>> return qemu_egl_create_context(dgc, params);
>>> }
>>> diff --git a/ui/egl-context.c b/ui/egl-context.c
>>> index aed3e3ba1f3f..f9a998768beb 100644
>>> --- a/ui/egl-context.c
>>> +++ b/ui/egl-context.c
>>> @@ -19,8 +19,7 @@ QEMUGLContext qemu_egl_create_context(DisplayGLCtx
>>> *dgc,
>>> };
>>> bool gles = (qemu_egl_mode == DISPLAY_GL_MODE_ES);
>>> - ctx = eglCreateContext(qemu_egl_display, qemu_egl_config,
>>> - eglGetCurrentContext(),
>>> + ctx = eglCreateContext(qemu_egl_display, qemu_egl_config,
>>> qemu_egl_rn_ctx,
>>> gles ? ctx_att_gles : ctx_att_core);
>>> return ctx;
>>> }
>>> diff --git a/ui/egl-headless.c b/ui/egl-headless.c
>>> index 1f6b845500dd..19955792ac95 100644
>>> --- a/ui/egl-headless.c
>>> +++ b/ui/egl-headless.c
>>> @@ -42,8 +42,6 @@ static void egl_gfx_switch(DisplayChangeListener *dcl,
>>> static QEMUGLContext egl_create_context(DisplayGLCtx *dgc,
>>> QEMUGLParams *params)
>>> {
>>> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
>>> - qemu_egl_rn_ctx);
>>> return qemu_egl_create_context(dgc, params);
>>> }
>>> diff --git a/ui/gtk-egl.c b/ui/gtk-egl.c
>>> index 0dbb429958e5..6b3519419039 100644
>>> --- a/ui/gtk-egl.c
>>> +++ b/ui/gtk-egl.c
>>> @@ -217,10 +217,6 @@ void gd_egl_switch(DisplayChangeListener *dcl,
>>> QEMUGLContext gd_egl_create_context(DisplayGLCtx *dgc,
>>> QEMUGLParams *params)
>>> {
>>> - VirtualConsole *vc = container_of(dgc, VirtualConsole, gfx.dgc);
>>> -
>>> - eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
>>> - vc->gfx.esurface, vc->gfx.ectx);
>>
>> This uses vc->gfx.ectx instead of qemu_egl_rn_ctx so it should be passed
>> to qemu_egl_create_context().
>
> Good catch. AFAICS, the vc->gfx.ectx is initialized only once in the
> code. Will double check.
>
> One problem with gtk-egl display is that this is the only display type I
> haven't tested because it's not obvious how to do it, The gdk-area is
> what always get used on my machine with both x11 and wayland, and
> forcing gtk-egl in the code instead of gdk-area results in a crash. I'd
> appreciate if anyone could clarify how to make QEMU use gtk-egl or
> whether it has been obsoleted and doesn't work with modern GTK.
>
The following worked for me:
GDK_BACKEND=x11 qemu-system-aarch64 -M virt -display gtk,gl=on
Regards,
Akihiko Odaki
On 3/3/26 15:52, Akihiko Odaki wrote:
> On 2026/03/03 21:05, Dmitry Osipenko wrote:
>> On 3/3/26 06:49, Akihiko Odaki wrote:
>>> On 2026/03/02 23:59, Dmitry Osipenko wrote:
>>>> Don't change bound GL context when creating new GL context for
>>>> consistency
>>>> with behavior expected by virglrenderer that assumes context-creation
>>>> doesn't
>>>> switch context. eglCreateContext() doesn't require GL context to be
>>>> bound
>>>> when it's invoked. Update qemu_egl_create_context() to spawn GL sub-
>>>> contexts
>>>> from a common parent GL context instead of a currently-bound context.
>>>>
>>>> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
>>>> ---
>>>> ui/dbus.c | 2 --
>>>> ui/egl-context.c | 3 +--
>>>> ui/egl-headless.c | 2 --
>>>> ui/gtk-egl.c | 4 ----
>>>> ui/spice-display.c | 2 --
>>>> 5 files changed, 1 insertion(+), 12 deletions(-)
>>>>
>>>> diff --git a/ui/dbus.c b/ui/dbus.c
>>>> index 905ee6fea71b..750a064e3fbf 100644
>>>> --- a/ui/dbus.c
>>>> +++ b/ui/dbus.c
>>>> @@ -47,8 +47,6 @@ static DBusDisplay *dbus_display;
>>>> static QEMUGLContext dbus_create_context(DisplayGLCtx *dgc,
>>>> QEMUGLParams *params)
>>>> {
>>>> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
>>>> - qemu_egl_rn_ctx);
>>>> return qemu_egl_create_context(dgc, params);
>>>> }
>>>> diff --git a/ui/egl-context.c b/ui/egl-context.c
>>>> index aed3e3ba1f3f..f9a998768beb 100644
>>>> --- a/ui/egl-context.c
>>>> +++ b/ui/egl-context.c
>>>> @@ -19,8 +19,7 @@ QEMUGLContext qemu_egl_create_context(DisplayGLCtx
>>>> *dgc,
>>>> };
>>>> bool gles = (qemu_egl_mode == DISPLAY_GL_MODE_ES);
>>>> - ctx = eglCreateContext(qemu_egl_display, qemu_egl_config,
>>>> - eglGetCurrentContext(),
>>>> + ctx = eglCreateContext(qemu_egl_display, qemu_egl_config,
>>>> qemu_egl_rn_ctx,
>>>> gles ? ctx_att_gles : ctx_att_core);
>>>> return ctx;
>>>> }
>>>> diff --git a/ui/egl-headless.c b/ui/egl-headless.c
>>>> index 1f6b845500dd..19955792ac95 100644
>>>> --- a/ui/egl-headless.c
>>>> +++ b/ui/egl-headless.c
>>>> @@ -42,8 +42,6 @@ static void egl_gfx_switch(DisplayChangeListener
>>>> *dcl,
>>>> static QEMUGLContext egl_create_context(DisplayGLCtx *dgc,
>>>> QEMUGLParams *params)
>>>> {
>>>> - eglMakeCurrent(qemu_egl_display, EGL_NO_SURFACE, EGL_NO_SURFACE,
>>>> - qemu_egl_rn_ctx);
>>>> return qemu_egl_create_context(dgc, params);
>>>> }
>>>> diff --git a/ui/gtk-egl.c b/ui/gtk-egl.c
>>>> index 0dbb429958e5..6b3519419039 100644
>>>> --- a/ui/gtk-egl.c
>>>> +++ b/ui/gtk-egl.c
>>>> @@ -217,10 +217,6 @@ void gd_egl_switch(DisplayChangeListener *dcl,
>>>> QEMUGLContext gd_egl_create_context(DisplayGLCtx *dgc,
>>>> QEMUGLParams *params)
>>>> {
>>>> - VirtualConsole *vc = container_of(dgc, VirtualConsole, gfx.dgc);
>>>> -
>>>> - eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
>>>> - vc->gfx.esurface, vc->gfx.ectx);
>>>
>>> This uses vc->gfx.ectx instead of qemu_egl_rn_ctx so it should be passed
>>> to qemu_egl_create_context().
>>
>> Good catch. AFAICS, the vc->gfx.ectx is initialized only once in the
>> code. Will double check.
>>
>> One problem with gtk-egl display is that this is the only display type I
>> haven't tested because it's not obvious how to do it, The gdk-area is
>> what always get used on my machine with both x11 and wayland, and
>> forcing gtk-egl in the code instead of gdk-area results in a crash. I'd
>> appreciate if anyone could clarify how to make QEMU use gtk-egl or
>> whether it has been obsoleted and doesn't work with modern GTK.
>>
>
> The following worked for me:
> GDK_BACKEND=x11 qemu-system-aarch64 -M virt -display gtk,gl=on
That works, thanks a lot.
--
Best regards,
Dmitry
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