commit e3e68ae41f1549cadb30b36ce2fef750ac17e6c8
author Raj kamal <rkamal@codeaurora.org> Thu May 02 17:28:23 2013 +0530
committer Gerrit - the friendly Code Review server <code-review@localhost> Thu May 02 10:14:23 2013 -0700
tree e747a88997b5be51e48dda2d75d72f88514a9b11
parent cc796a207e99e60e382a2f1a93686d51581b6466

Fix crash issue arising out of multiple hdmi connect/disconnects

Acquire mExtLock before proceeding further in
hwc_prepare_external to prevent crashes arising out
of updating ctx variables from two different
threads(composition and uevent threads)

Change-Id: I0f18c41b117f18aeb25572b53ef6eba3638bb826

libhwcomposer/hwc.cpp

diff --git a/libhwcomposer/hwc.cpp b/libhwcomposer/hwc.cpp
index 9bf0c45..7bfbf06 100644
--- a/libhwcomposer/hwc.cpp
+++ b/libhwcomposer/hwc.cpp
@@ -158,7 +158,9 @@
 
 static int hwc_prepare_external(hwc_composer_device_1 *dev,
         hwc_display_contents_1_t *list, int dpy) {
+
     hwc_context_t* ctx = (hwc_context_t*)(dev);
+    Locker::Autolock _l(ctx->mExtLock);
 
     if (LIKELY(list && list->numHwLayers > 1) &&
             ctx->dpyAttr[dpy].isActive &&
@@ -398,7 +400,7 @@
 {
     ATRACE_CALL();
     int ret = 0;
-    Locker::Autolock _l(ctx->mExtSetLock);
+    Locker::Autolock _l(ctx->mExtLock);
 
     if (LIKELY(list) && ctx->dpyAttr[dpy].isActive &&
         !ctx->dpyAttr[dpy].isPause &&

libhwcomposer/hwc_uevents.cpp

diff --git a/libhwcomposer/hwc_uevents.cpp b/libhwcomposer/hwc_uevents.cpp
index eb525a6..b314317 100644
--- a/libhwcomposer/hwc_uevents.cpp
+++ b/libhwcomposer/hwc_uevents.cpp
@@ -148,7 +148,7 @@
                 }else if(!strncmp(s1,"wfd",strlen(s1))) {
                     ctx->mExtDisplay->teardownWFDDisplay();
                 }
-                Locker::Autolock _l(ctx->mExtSetLock);
+                Locker::Autolock _l(ctx->mExtLock);
                 clear(ctx, dpy);
                 ALOGD("%s sending hotplug: connected = %d and dpy:%d",
                       __FUNCTION__, connected, dpy);
@@ -170,7 +170,7 @@
                         // teardown Active WFD Display
                         ctx->mExtDisplay->teardownWFDDisplay();
                         {
-                            Locker::Autolock _l(ctx->mExtSetLock);
+                            Locker::Autolock _l(ctx->mExtLock);
                             clear(ctx, dpy);
                             //send hotplug disconnect event
                             ALOGD_IF(UEVENT_DEBUG, "sending hotplug: disconnect"
@@ -195,7 +195,7 @@
                 ALOGD("%s sending hotplug: connected = %d", __FUNCTION__,
                         connected);
                 ctx->dpyAttr[dpy].connected = true;
-                Locker::Autolock _l(ctx->mExtSetLock); //hwc comp could be on
+                Locker::Autolock _l(ctx->mExtLock); //hwc comp could be on
                 ctx->proc->hotplug(ctx->proc, dpy, connected);
                 break;
             }

libhwcomposer/hwc_utils.h

diff --git a/libhwcomposer/hwc_utils.h b/libhwcomposer/hwc_utils.h
index e0fff77..6e95703 100644
--- a/libhwcomposer/hwc_utils.h
+++ b/libhwcomposer/hwc_utils.h
@@ -269,8 +269,8 @@
     bool mSecureMode;
     //Lock to prevent set from being called while blanking
     mutable Locker mBlankLock;
-    //Lock to protect set when detaching external disp
-    mutable Locker mExtSetLock;
+    //Lock to protect prepare & set when detaching external disp
+    mutable Locker mExtLock;
     //Vsync
     struct vsync_state vstate;
     //Drawing round when we use GPU