Fix crashes after HDMI disconnect

The display was being removed from SurfaceFlinger's list before we
had a chance to reset HWComposer's layer list, so we were passing
stale data into the hardware composer (which has its own per-display
data).  This resulted in "invalid gralloc handle" complaints.
We now clear the layer list immediately after removing the display.

The display was being removed while its EGLSurface was still
"current", resulting in "cancelBuffer: BufferQueue has been
abandoned" complaints.  We now call makeCurrent on the primary
display before removing the external display.

Bug 7274254

Change-Id: Ia59e3a61d7ec46488b96bf93ec5e4ed3488b70e4

2 files changed, 19 insertions, 0 deletions

diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index fb93c47..302ce82 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -540,8 +540,13 @@ status_t HWComposer::prepare() {
             // DO NOT reset the handle field to NULL, because it's possible
             // that we have nothing to redraw (eg: eglSwapBuffers() not called)
             // in which case, we should continue to use the same buffer.
+            LOG_FATAL_IF(disp.list == NULL);
             disp.framebufferTarget->compositionType = HWC_FRAMEBUFFER_TARGET;
         }
+        if (!disp.connected && disp.list != NULL) {
+            ALOGW("WARNING: disp %d: connected, non-null list, layers=%d",
+                  i, disp.list->numHwLayers);
+        }
         mLists[i] = disp.list;
         if (mLists[i]) {
             if (hwcHasApiVersion(mHwc, HWC_DEVICE_API_VERSION_1_2)) {
@@ -664,6 +669,17 @@ status_t HWComposer::acquire(int disp) const {
     return NO_ERROR;
 }
 
+void HWComposer::disconnectDisplay(int disp) {
+    LOG_ALWAYS_FATAL_IF(disp < 0 || disp == HWC_DISPLAY_PRIMARY ||
+                        disp >= HWC_NUM_DISPLAY_TYPES);
+    DisplayData& dd(mDisplayData[disp]);
+    if (dd.list != NULL) {
+        free(dd.list);
+        dd.list = NULL;
+        dd.framebufferTarget = NULL;    // points into dd.list
+    }
+}
+
 int HWComposer::getVisualID() const {
     if (mHwc && hwcHasApiVersion(mHwc, HWC_DEVICE_API_VERSION_1_1)) {
         // FIXME: temporary hack until HAL_PIXEL_FORMAT_IMPLEMENTATION_DEFINED
diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.h b/services/surfaceflinger/DisplayHardware/HWComposer.h
index 633ca9c..af33999 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.h
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.h
@@ -97,6 +97,9 @@ public:
     // acquire hardware resources and unblank screen
     status_t acquire(int disp) const;
 
+    // reset state when an external, non-virtual display is disconnected
+    void disconnectDisplay(int disp);
+
     // create a work list for numLayers layer. sets HWC_GEOMETRY_CHANGED.
     status_t createWorkList(int32_t id, size_t numLayers);