[Fix] (DirectVulkan): suspend presentation while the window is zero-area - a minimized window's out-of-date swapchain used to keep Present submitting on a signaled fence and presenting never-acquired images (adversarial review); also drop logging from the process-detach abandon path

MobileGL/Init.cpp

@@ -95,15 +95,16 @@ namespace MobileGL {
         // inside a dying process - other threads have already been terminated,
         // so Vulkan/GLES cleanup crashes with the process half-dead. The process
         // is exiting; the OS reclaims everything.
+        // No logging here: this runs under the loader lock after every other
+        // thread was terminated, where the log mutex/heap/stdio may be in any
+        // state. Plain pointer stores only.
         void AbandonAtProcessExit() {
-            MGLOG_I("MobileGL: process detach, abandoning global state");
             MG_Backend::DirectVulkan::pVulkanRenderer.release();
             MG_Backend::pActiveBackendObject.release();
             MG_State::pGLContext.release();
             MG_State::pEGLContext.release();
             MG_Impl::GLImpl::TextureImpl::pProxyTextureManager.release();
             MG_Impl::GLImpl::FramebufferImpl::pDefaultFramebufferInfo.release();
-            MGLOG_I("MobileGL: global state abandoned");
         }
     } // namespace
 #endif

MobileGL/MG_Backend/DirectVulkan/Renderer/VulkanRenderer.cpp

@@ -6865,18 +6865,32 @@ void main() {
     }
 
     void VulkanRenderer::Present() {
-        if (m_swapchainObject.GetHandle() == VK_NULL_HANDLE) {
-            // No swapchain yet (the window had a zero-area surface at initialization).
-            // Try to bring one up now that the window may have a real size; if it is
-            // still zero-area there is nothing to present to.
-            RecreateSwapchain();
-            if (m_swapchainObject.GetHandle() == VK_NULL_HANDLE) {
-                MGLOG_D("Present skipped: still no swapchain (zero-area window)");
+        if (m_swapchainObject.GetHandle() == VK_NULL_HANDLE || m_presentSuspended) {
+            // No usable swapchain: the window was zero-area at initialization, or
+            // presentation was suspended when the window minimized. Try to bring a
+            // swapchain up now that the window may have a real size; until then, drop
+            // this frame's recording instead of submitting - a submit would wait on a
+            // never-signaled acquire semaphore and reuse a still-signaled fence.
+            if (!RecreateSwapchain()) {
+                auto& suspendedFrame = m_frameContext.GetCurrent();
+                if (VkRenderPassManager::GetActiveRenderPass()) {
+                    VkRenderPassManager::EndRenderPass(suspendedFrame.commandBuffer);
+                }
+                if (suspendedFrame.isCommandRecording) {
+                    m_frameContext.EndCommandRecording();
+                }
+                suspendedFrame.isCommandRecording = false;
+                suspendedFrame.hasCommandBufferRecorded = false;
+                m_lastPipelineValid = false;
+                MGLOG_D("Present skipped: no usable swapchain (zero-area window)");
                 return;
             }
+            m_presentSuspended = false;
             const VkResult acquireResult =
                 m_frameContext.WaitAndAcquireNextImage(m_device, m_swapchainObject.GetHandle(), m_imageIndexAcquired);
-            VK_VERIFY(acquireResult, "Present, deferred first WaitAndAcquireNextImage");
+            if (acquireResult != VK_SUBOPTIMAL_KHR) {
+                VK_VERIFY(acquireResult, "Present, deferred first WaitAndAcquireNextImage");
+            }
         }
         MOBILEGL_ASSERT(m_imageIndexAcquired < m_swapchainObject.GetImageCount(),
                         "Present, acquired image index out of range");
@@ -6911,14 +6925,26 @@ void main() {
         auto result = vkQueuePresentKHR(m_presentQueue, &presentPacket.presentInfo);
         if (result == VK_ERROR_OUT_OF_DATE_KHR || result == VK_SUBOPTIMAL_KHR) {
             MGLOG_D("Present, vkQueuePresentKHR got %d, recreating swapchain", result);
-            RecreateSwapchain();
+            if (!RecreateSwapchain()) {
+                // Window went zero-area (minimize) with the swapchain out of date:
+                // stop submitting/acquiring until it has a size again.
+                m_presentSuspended = true;
+                m_swapchainResizeRequested = false;
+                MGLOG_D("Present, zero-area window with out-of-date swapchain; suspending presentation");
+                return;
+            }
             m_swapchainResizeRequested = false;
             result = VK_SUCCESS;
         }
         VK_VERIFY(result, "Present, vkQueuePresentKHR");
         if (m_swapchainResizeRequested) {
             MGLOG_D("Present, processing requested swapchain resize");
-            RecreateSwapchain();
+            if (!RecreateSwapchain()) {
+                m_presentSuspended = true;
+                m_swapchainResizeRequested = false;
+                MGLOG_D("Present, zero-area window on requested resize; suspending presentation");
+                return;
+            }
             m_swapchainResizeRequested = false;
         }
 
@@ -6929,7 +6955,12 @@ void main() {
         result = m_frameContext.WaitAndAcquireNextImage(m_device, m_swapchainObject.GetHandle(), m_imageIndexAcquired);
         if (result == VK_ERROR_OUT_OF_DATE_KHR || result == VK_SUBOPTIMAL_KHR) {
             MGLOG_D("Present, vkAcquireNextImageKHR got %d, recreating swapchain", result);
-            RecreateSwapchain();
+            if (!RecreateSwapchain()) {
+                m_presentSuspended = true;
+                m_swapchainResizeRequested = false;
+                MGLOG_D("Present, zero-area window on next-frame acquire; suspending presentation");
+                return;
+            }
             m_swapchainResizeRequested = false;
             result =
                 m_frameContext.WaitAndAcquireNextImage(m_device, m_swapchainObject.GetHandle(), m_imageIndexAcquired);
@@ -7743,13 +7774,13 @@ void main() {
         m_swapchainObject.Shutdown(m_device);
     }
 
-    void VulkanRenderer::RecreateSwapchain() {
+    Bool VulkanRenderer::RecreateSwapchain() {
         // Handle cases like minimize on Windows, where swapchain could return a 0x0 extent
         const auto swapchainCapabilities =
             SwapchainObject::GetSwapchainCapabilities(m_physicalDevice.handle, m_surface);
         if (swapchainCapabilities.capabilities.currentExtent.width == 0 ||
             swapchainCapabilities.capabilities.currentExtent.height == 0) {
-            return;
+            return false;
         }
 
         vkDeviceWaitIdle(m_device);
@@ -7793,6 +7824,7 @@ void main() {
             m_bufferManager.BeginFrame(m_frameContext.GetCurrentFrameIndex());
             m_convertedVertexStreams.clear();
         }
+        return true;
     }
 
     const PhysicalDevice& VulkanRenderer::GetPhysicalDevice() const {

MobileGL/MG_Backend/DirectVulkan/Renderer/VulkanRenderer.h

@@ -257,7 +257,9 @@ namespace MobileGL::MG_Backend::DirectVulkan {
         Uint64 GetTimerQueryTimestampNs(const VkTimerQueryManager::TimestampRecord& record) const;
 
         void RequestSwapchainResize(Uint32 width, Uint32 height);
-        void RecreateSwapchain();
+        // Returns false when the surface is zero-area (minimized/hidden window):
+        // no new swapchain is installed and presentation must stay suspended.
+        Bool RecreateSwapchain();
 
     private:
         struct BlitUniformData {
@@ -355,6 +357,10 @@ namespace MobileGL::MG_Backend::DirectVulkan {
         void* m_platformCloseDisplay = nullptr;
         VulkanRendererConfig m_config;
         Bool m_swapchainResizeRequested = false;
+        // Presentation is suspended while the window is zero-area (minimized): the
+        // swapchain is unusable/out of date, so Present drops frames instead of
+        // submitting on a signaled fence / presenting never-acquired images.
+        Bool m_presentSuspended = false;
 
         // Vulkan objects
         Bool m_validationLayersEnabled = false;