diff --git a/src/java.base/share/classes/sun/nio/ch/NioSocketImpl.java b/src/java.base/share/classes/sun/nio/ch/NioSocketImpl.java
index b9885a36fa8..848b548bb3f 100644
--- a/src/java.base/share/classes/sun/nio/ch/NioSocketImpl.java
+++ b/src/java.base/share/classes/sun/nio/ch/NioSocketImpl.java
@@ -295,8 +295,10 @@ private int implRead(byte[] b, int off, int len) throws IOException {
         try {
             if (connectionReset)
                 throw new SocketException("Connection reset");
-            if (isInputClosed)
+            if (isInputClosed) {
+                System.err.println("input is closed, returning EOF");
                 return -1;
+            }
             int timeout = this.timeout;
             configureNonBlockingIfNeeded(fd, timeout > 0);
             if (timeout > 0) {
@@ -310,6 +312,9 @@ private int implRead(byte[] b, int off, int len) throws IOException {
                     n = tryRead(fd, b, off, len);
                 }
             }
+            if (n == -1) {
+                System.err.println("Socket read() returning -1");
+            }
             return n;
         } catch (InterruptedIOException e) {
             throw e;
@@ -339,13 +344,17 @@ private int read(byte[] b, int off, int len) throws IOException {
             readLock.lock();
             try {
                 // emulate legacy behavior to return -1, even if socket is closed
-                if (readEOF)
+                if (readEOF) {
+                    System.err.println("already reached EOF, returning -1");
                     return -1;
+                }
                 // read up to MAX_BUFFER_SIZE bytes
                 int size = Math.min(len, MAX_BUFFER_SIZE);
                 int n = implRead(b, off, size);
-                if (n == -1)
+                if (n == -1) {
+                    System.err.println("marking EOF");
                     readEOF = true;
+                }
                 return n;
             } finally {
                 readLock.unlock();
diff --git a/src/java.base/unix/native/libnio/ch/SocketDispatcher.c b/src/java.base/unix/native/libnio/ch/SocketDispatcher.c
index bb987fc3b3d..546e82efcd4 100644
--- a/src/java.base/unix/native/libnio/ch/SocketDispatcher.c
+++ b/src/java.base/unix/native/libnio/ch/SocketDispatcher.c
@@ -45,7 +45,11 @@
          JNU_ThrowByName(env, "sun/net/ConnectionResetException", "Connection reset");
          return IOS_THROWN;
      } else {
-         return convertReturnVal(env, n, JNI_TRUE);
+         int read_ret = convertReturnVal(env, n, JNI_TRUE);
+         if (read_ret == -1) {
+            fprintf(stderr, "underlying read returned %d, returning EOF\n", n);
+         }
+         return read_ret;
      }
  }