diff --git a/netwerk/protocol/http/SpdySession31.cpp b/netwerk/protocol/http/SpdySession31.cpp
index 97efc0e9c414..3f442837b71b 100644
--- a/netwerk/protocol/http/SpdySession31.cpp
+++ b/netwerk/protocol/http/SpdySession31.cpp
@@ -2102,6 +2102,13 @@ SpdySession31::WriteSegments(nsAHttpSegmentWriter *writer,
     SpdyStream31 *stream = mInputFrameDataStream;
     mSegmentWriter = writer;
     rv = mInputFrameDataStream->WriteSegments(this, count, countWritten);
+    bool channelPipeFull = false;
+    if (rv == NS_BASE_STREAM_WOULD_BLOCK) {
+      LOG3(("SpdySession31::WriteSegments session=%p stream=%p 0x%X "
+            "stream channel pipe full\n",
+            this, stream, stream ? stream->StreamID() : 0));
+      channelPipeFull = mInputFrameDataStream->ChannelPipeFull();
+    }
     mSegmentWriter = nullptr;
 
     mLastDataReadEpoch = mLastReadEpoch;
@@ -2137,10 +2144,13 @@ SpdySession31::WriteSegments(nsAHttpSegmentWriter *writer,
     }
 
     if (NS_FAILED(rv)) {
-      LOG3(("SpdySession31 %p data frame read failure %x\n", this, rv));
+      LOG3(("SpdySession31::WriteSegments session=%p stream=%p 0x%X "
+            "data frame read failure %x pipefull=%d\n",
+            this, stream, stream ? stream->StreamID() : 0, rv, channelPipeFull));
       // maybe just blocked reading from network
-      if (rv == NS_BASE_STREAM_WOULD_BLOCK)
+      if ((rv == NS_BASE_STREAM_WOULD_BLOCK) && !channelPipeFull) {
         rv = NS_OK;
+      }
     }
 
     return rv;
diff --git a/netwerk/protocol/http/SpdyStream31.cpp b/netwerk/protocol/http/SpdyStream31.cpp
index b3f6eaf386d7..746e5d57b854 100644
--- a/netwerk/protocol/http/SpdyStream31.cpp
+++ b/netwerk/protocol/http/SpdyStream31.cpp
@@ -229,6 +229,13 @@ SpdyStream31::WriteSegments(nsAHttpSegmentWriter *writer,
   return rv;
 }
 
+bool
+SpdyStream31::ChannelPipeFull()
+{
+  nsHttpTransaction *trans = mTransaction ? mTransaction->QueryHttpTransaction() : nullptr;
+  return trans ? trans->ChannelPipeFull() : false;
+}
+
 void
 SpdyStream31::CreatePushHashKey(const nsCString &scheme,
                                 const nsCString &hostHeader,
diff --git a/netwerk/protocol/http/SpdyStream31.h b/netwerk/protocol/http/SpdyStream31.h
index 6408c5cf145e..5502e9380058 100644
--- a/netwerk/protocol/http/SpdyStream31.h
+++ b/netwerk/protocol/http/SpdyStream31.h
@@ -88,6 +88,7 @@ public:
   int64_t  LocalWindow()  { return mLocalWindow; }
 
   bool     BlockedOnRwin() { return mBlockedOnRwin; }
+  bool     ChannelPipeFull();
 
   // A pull stream has an implicit sink, a pushed stream has a sink
   // once it is matched to a pull stream.
diff --git a/netwerk/protocol/http/nsHttpConnection.cpp b/netwerk/protocol/http/nsHttpConnection.cpp
index 968938855c89..9ecaf866db09 100644
--- a/netwerk/protocol/http/nsHttpConnection.cpp
+++ b/netwerk/protocol/http/nsHttpConnection.cpp
@@ -1765,23 +1765,27 @@ nsHttpConnection::OnSocketReadable()
             break;
         }
 
+        mSocketInCondition = NS_OK;
         rv = mTransaction->WriteSegments(this, nsIOService::gDefaultSegmentSize, &n);
+        LOG(("nsHttpConnection::OnSocketReadable %p trans->ws rv=%x n=%d socketin=%x\n",
+             this, rv, n, mSocketInCondition));
         if (NS_FAILED(rv)) {
             // if the transaction didn't want to take any more data, then
             // wait for the transaction to call ResumeRecv.
-            if (rv == NS_BASE_STREAM_WOULD_BLOCK)
+            if (rv == NS_BASE_STREAM_WOULD_BLOCK) {
                 rv = NS_OK;
+            }
             again = false;
-        }
-        else {
+        } else {
             mCurrentBytesRead += n;
             mTotalBytesRead += n;
             if (NS_FAILED(mSocketInCondition)) {
                 // continue waiting for the socket if necessary...
-                if (mSocketInCondition == NS_BASE_STREAM_WOULD_BLOCK)
+                if (mSocketInCondition == NS_BASE_STREAM_WOULD_BLOCK) {
                     rv = ResumeRecv();
-                else
+                } else {
                     rv = mSocketInCondition;
+                }
                 again = false;
             }
         }
diff --git a/netwerk/protocol/http/nsHttpTransaction.cpp b/netwerk/protocol/http/nsHttpTransaction.cpp
index a1e03e287975..e25b581d0727 100644
--- a/netwerk/protocol/http/nsHttpTransaction.cpp
+++ b/netwerk/protocol/http/nsHttpTransaction.cpp
@@ -127,6 +127,7 @@ nsHttpTransaction::nsHttpTransaction()
     , mContentDecoding(false)
     , mContentDecodingCheck(false)
     , mDeferredSendProgress(false)
+    , mWaitingOnPipeOut(false)
     , mReportedStart(false)
     , mReportedResponseHeader(false)
     , mForTakeResponseHead(nullptr)
@@ -832,9 +833,10 @@ nsHttpTransaction::WriteSegments(nsAHttpSegmentWriter *writer,
     if (rv == NS_BASE_STREAM_WOULD_BLOCK) {
         nsCOMPtr<nsIEventTarget> target;
         gHttpHandler->GetSocketThreadTarget(getter_AddRefs(target));
-        if (target)
+        if (target) {
             mPipeOut->AsyncWait(this, 0, 0, target);
-        else {
+            mWaitingOnPipeOut = true;
+        } else {
             NS_ERROR("no socket thread event target");
             rv = NS_ERROR_UNEXPECTED;
         }
@@ -2179,6 +2181,7 @@ NS_IMPL_QUERY_INTERFACE(nsHttpTransaction,
 NS_IMETHODIMP
 nsHttpTransaction::OnInputStreamReady(nsIAsyncInputStream *out)
 {
+    MOZ_ASSERT(PR_GetCurrentThread() == gSocketThread);
     if (mConnection) {
         mConnection->TransactionHasDataToWrite(this);
         nsresult rv = mConnection->ResumeSend();
@@ -2196,6 +2199,8 @@ nsHttpTransaction::OnInputStreamReady(nsIAsyncInputStream *out)
 NS_IMETHODIMP
 nsHttpTransaction::OnOutputStreamReady(nsIAsyncOutputStream *out)
 {
+    MOZ_ASSERT(PR_GetCurrentThread() == gSocketThread);
+    mWaitingOnPipeOut = false;
     if (mConnection) {
         mConnection->TransactionHasDataToRecv(this);
         nsresult rv = mConnection->ResumeRecv();
diff --git a/netwerk/protocol/http/nsHttpTransaction.h b/netwerk/protocol/http/nsHttpTransaction.h
index b7021dc1311a..ce82230ba4d5 100644
--- a/netwerk/protocol/http/nsHttpTransaction.h
+++ b/netwerk/protocol/http/nsHttpTransaction.h
@@ -143,6 +143,7 @@ public:
     }
     void SetPushedStream(Http2PushedStream *push) { mPushedStream = push; }
     uint32_t InitialRwin() const { return mInitialRwin; };
+    bool ChannelPipeFull() { return mWaitingOnPipeOut; }
 
     // Locked methods to get and set timing info
     const TimingStruct Timings();
@@ -306,6 +307,7 @@ private:
     bool                            mContentDecoding;
     bool                            mContentDecodingCheck;
     bool                            mDeferredSendProgress;
+    bool                            mWaitingOnPipeOut;
 
     // mClosed           := transaction has been explicitly closed
     // mTransactionDone  := transaction ran to completion or was interrupted