--- src/mesa/drivers/dri/r128.bak/r128_context.h	2007-02-06 17:28:55.000000000 +0100
+++ src/mesa/drivers/dri/r128/r128_context.h	2007-02-06 17:50:54.000000000 +0100
@@ -218,6 +218,8 @@
    /* Configuration cache
     */
    driOptionCache optionCache;
+
+   GLboolean span_dlocking;
 };
 
 #define R128_CONTEXT(ctx)		((r128ContextPtr)(ctx->DriverCtx))
--- src/mesa/drivers/dri/r128.bak/r128_span.c	2007-02-06 17:28:55.000000000 +0100
+++ src/mesa/drivers/dri/r128/r128_span.c	2007-02-06 18:07:39.000000000 +0100
@@ -34,6 +34,8 @@
  *
  */
 
+#include <unistd.h>
+
 #include "r128_context.h"
 #include "r128_ioctl.h"
 #include "r128_state.h"
@@ -403,6 +405,29 @@
 r128SpanRenderStart( GLcontext *ctx )
 {
    r128ContextPtr rmesa = R128_CONTEXT(ctx);
+   {
+        static int first = 1;
+
+        if (first) {
+                rmesa->span_dlocking = getenv("R128_SPAN_ENABLE_LOCKING") ? 0 : 1;
+                if (rmesa->span_dlocking == 0) {
+                        fprintf(stderr, "You set R128_SPAN_ENABLE_LOCKING env var\nit may cause hanging in some apps.");
+                        fflush(stderr);
+                        sleep(1);
+                }
+                first = 0;
+        }
+
+        if (rmesa->span_dlocking) {
+                FLUSH_BATCH(rmesa);
+                LOCK_HARDWARE( rmesa );
+                r128WaitForIdleLocked( rmesa );
+                UNLOCK_HARDWARE( rmesa );
+
+                return;
+        }
+   }
+
    FLUSH_BATCH(rmesa);
    LOCK_HARDWARE(rmesa);
    r128WaitForIdleLocked( rmesa );
@@ -413,8 +438,8 @@
 {
    r128ContextPtr rmesa = R128_CONTEXT(ctx);
    _swrast_flush( ctx );
-   r128WaitForIdleLocked( rmesa );
-   UNLOCK_HARDWARE( rmesa );
+   if (rmesa->span_dlocking == 0)
+        UNLOCK_HARDWARE( rmesa );
 }
 
 void r128DDInitSpanFuncs( GLcontext *ctx )