From a98e4195f567b39af9fd8a6cfccec6f772efe9fc Mon Sep 17 00:00:00 2001 From: Pierre-Eric Pelloux-Prayer Date: Tue, 24 Jan 2023 21:42:49 +0100 Subject: [PATCH] yegl/wayland: fix glthread deadlocks MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We need to make sure that glthread is idle before using wl_* functions or they might be used from 2 threads at the same time. Thanks to @deltib for the investigation of this issue. Fixes: 58f90fd03f4 ("egl/wayland: fix glthread crashes") Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/7624 Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/8136 Reviewed-by: Michel Dänzer Reviewed-by: Marek Olšák Part-of: --- src/egl/drivers/dri2/platform_wayland.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/src/egl/drivers/dri2/platform_wayland.c b/src/egl/drivers/dri2/platform_wayland.c index 209a77143ec..fe152294a85 100644 --- a/src/egl/drivers/dri2/platform_wayland.c +++ b/src/egl/drivers/dri2/platform_wayland.c @@ -1588,6 +1588,19 @@ dri2_wl_swap_buffers_with_damage(_EGLDisplay *disp, if (!dri2_surf->wl_win) return _eglError(EGL_BAD_NATIVE_WINDOW, "dri2_swap_buffers"); + /* Flush (and finish glthread) before: + * - update_buffers_if_needed because the unmarshalling thread + * may be running currently, and we would concurrently alloc/free + * the back bo. + * - swapping current/back because flushing may free the buffer and + * dri_image and reallocate them using get_back_bo (which causes a + * a crash because 'current' becomes NULL). + * - using any wl_* function because accessing them from this thread + * and glthread causes troubles (see #7624 and #8136) + */ + dri2_flush_drawable_for_swapbuffers(disp, draw); + dri2_dpy->flush->invalidate(dri2_surf->dri_drawable); + while (dri2_surf->throttle_callback != NULL) if (wl_display_dispatch_queue(dri2_dpy->wl_dpy, dri2_surf->wl_queue) == -1) @@ -1597,17 +1610,6 @@ dri2_wl_swap_buffers_with_damage(_EGLDisplay *disp, if (dri2_surf->color_buffers[i].age > 0) dri2_surf->color_buffers[i].age++; - /* Flush (and finish glthread) before: - * - update_buffers_if_needed because the unmarshalling thread - * may be running currently, and we would concurrently alloc/free - * the back bo. - * - swapping current/back because flushing may free the buffer and - * dri_image and reallocate them using get_back_bo (which causes a - * a crash because 'current' becomes NULL). - */ - dri2_flush_drawable_for_swapbuffers(disp, draw); - dri2_dpy->flush->invalidate(dri2_surf->dri_drawable); - /* Make sure we have a back buffer in case we're swapping without ever * rendering. */ if (update_buffers_if_needed(dri2_surf) < 0)