Comfy-Org/ComfyUI · error · RuntimeError

eglCreateContext() failed

Error message

eglCreateContext() failed

What it means

Raised during GLContext initialization when eglCreateContext() with EGL_CONTEXT_CLIENT_VERSION=3 returns EGL_NO_CONTEXT. The display and pbuffer surface were created fine, but the driver refused to create a GLES 3.x context on the chosen config. The GLSL nodes require OpenGL ES 3.0 (MRT rendering to RGBA32F textures), so a GLES2-only stack fails here.

Source

Thrown at comfy_extras/nodes_glsl.py:285

                    EGL.EGL_BLUE_SIZE, 8, EGL.EGL_ALPHA_SIZE, 8,
                ),
                ctypes.byref(config), 1, ctypes.byref(n_configs),
            ) or n_configs.value == 0:
                raise RuntimeError("eglChooseConfig() failed")

            self._surface = EGL.eglCreatePbufferSurface(
                self._display, config,
                _egl_attribs(EGL.EGL_WIDTH, 64, EGL.EGL_HEIGHT, 64),
            )
            if not self._surface:
                raise RuntimeError("eglCreatePbufferSurface() failed")

            self._context = EGL.eglCreateContext(
                self._display, config, EGL.EGL_NO_CONTEXT,
                _egl_attribs(EGL.EGL_CONTEXT_CLIENT_VERSION, 3),
            )
            if not self._context:
                raise RuntimeError("eglCreateContext() failed")

            if not EGL.eglMakeCurrent(self._display, self._surface, self._surface, self._context):
                raise RuntimeError("eglMakeCurrent() failed")

            self._vao = gl.glGenVertexArrays(1)
            gl.glBindVertexArray(self._vao)

        except Exception:
            self._cleanup()
            raise

        elapsed = (time.perf_counter() - start) * 1000

        renderer = _gl_str(gl.GL_RENDERER)
        vendor = _gl_str(gl.GL_VENDOR)
        version = _gl_str(gl.GL_VERSION)

        GLContext._initialized = True

View on GitHub (pinned to 1c6d8d45b3)

Solutions

  1. Install the GLES3 runtime: apt install libgles3-mesa libegl-mesa0 (or distro equivalent) inside the container/host.
  2. Confirm ES3 support with eglinfo / es2_info: look for 'OpenGL ES 3.x' in the client APIs string.
  3. Update the GPU driver to a version with working EGL + GLES3 (especially NVIDIA >= 470 and recent Mesa).
  4. As a last resort on machines without GLES3, use non-GLSL image-manipulation nodes.
Defensive patterns

Strategy: validation

Validate before calling

# Before using GLSL nodes, confirm ES3 context creation is possible:
# eglinfo -B should list "OpenGL ES 3.x" under client APIs / supported contexts.
import subprocess, sys
r = subprocess.run(["eglinfo", "-B"], capture_output=True, text=True)
if "OpenGL ES 3" not in (r.stdout + r.stderr):
    print("Warning: GLES3 not available; GLSL nodes will fail at eglCreateContext")

Try / catch

try:
    out = glsl_render_node(...)
except RuntimeError as e:
    if "eglCreateContext" in str(e):
        # fall back to a torch-based equivalent effect node
        out = torch_fallback_effect(...)
    else:
        raise

Prevention

When it happens

Trigger: eglChooseConfig matched a config whose RENDERABLE_TYPE bits allow ES3 but the driver cannot create a version-3 context (driver bug or mismatched vendor); EGL 1.4-only implementations without proper ES3 support; containers with only libgles2 (GLES2) installed while libgles3 is missing.

Common situations: Minimal Docker images that install libgles2 but not libgles3; older embedded/ARM drivers advertising ES3 configs but lacking a working ES3 runtime; mixing Mesa EGL with proprietary GL libraries.

Related errors

AI-assisted analysis of Comfy-Org/ComfyUI@1c6d8d45b3 (2026-08-14). Data as JSON: /api/errors/893ee773cb0b82c2. Report an issue: GitHub.