3 files changed, 29 insertions, 17 deletions

diff --git a/src/vmware.c b/src/vmware.c
index 60a3004..5d29f72 100644
--- a/src/vmware.c
+++ b/src/vmware.c
@@ -1784,8 +1784,7 @@ VMWAREScreenInit(int scrnIndex, ScreenPtr pScreen, int argc, char **argv)
      * We will lazily add the dynamic modes as the are needed when new
      * modes are requested through the control extension.
      */
-    pVMWARE->dynMode1 = NULL;
-    pVMWARE->dynMode2 = NULL;
+    memset(&pVMWARE->dynModes, 0, sizeof pVMWARE->dynModes);
 
 #if VMWARE_DRIVER_FUNC
     pScrn->DriverFunc = VMWareDriverFunc;
diff --git a/src/vmware.h b/src/vmware.h
index 2b3c119..80393e6 100644
--- a/src/vmware.h
+++ b/src/vmware.h
@@ -46,6 +46,9 @@
 /* Arbitrarily choose max cursor dimensions.  The emulation doesn't care. */
 #define MAX_CURS        32
 
+#define NUM_DYN_MODES   2
+
+
 typedef struct {
     CARD32 svga_reg_enable;
     CARD32 svga_reg_width;
@@ -94,8 +97,7 @@ typedef struct {
     VMWARERegRec SavedReg;
     VMWARERegRec ModeReg;
 
-    DisplayModePtr dynMode1;
-    DisplayModePtr dynMode2;
+    DisplayModePtr dynModes[NUM_DYN_MODES];
 
     Bool* pvtSema;
 
diff --git a/src/vmwarectrl.c b/src/vmwarectrl.c
index 24865d6..634b9ca 100644
--- a/src/vmwarectrl.c
+++ b/src/vmwarectrl.c
@@ -116,19 +116,20 @@ VMwareCtrlDoSetRes(ScrnInfoPtr pScrn,
                    CARD32 y,
                    Bool resetXinerama)
 {
+   int modeIndex;
    DisplayModePtr mode;
    VMWAREPtr pVMWARE = VMWAREPTR(pScrn);
 
    if (pScrn && pScrn->modes) {
       VmwareLog(("DoSetRes: %d %d\n", x, y));
-  
+
       if (resetXinerama) {
          xfree(pVMWARE->xineramaNextState);
          pVMWARE->xineramaNextState = NULL;
          pVMWARE->xineramaNextNumOutputs = 0;
       }
 
-      /* 
+      /*
        * Don't resize larger than possible but don't
        * return an X Error either.
        */
@@ -138,20 +139,30 @@ VMwareCtrlDoSetRes(ScrnInfoPtr pScrn,
       }
 
       /*
-       * Switch the dynamic modes so that we alternate
-       * which one gets updated on each call.
+       * Find an dynamic mode which isn't current, and replace it with
+       * the requested mode. Normally this will cause us to alternate
+       * between two dynamic mode slots, but there are some important
+       * corner cases to consider. For example, adding the same mode
+       * multiple times, adding a mode that we never switch to, or
+       * adding a mode which is a duplicate of a built-in mode. The
+       * best way to handle all of these cases is to directly test the
+       * dynamic mode against the current mode pointer for this
+       * screen.
        */
-      mode = pVMWARE->dynMode1;
-      pVMWARE->dynMode1 = pVMWARE->dynMode2;
-      pVMWARE->dynMode2 = mode;
 
-      /*
-       * Initialise the dynamic mode if it hasn't been used before.
-       */
-      if (!pVMWARE->dynMode1) {
-         pVMWARE->dynMode1 = VMWAREAddDisplayMode(pScrn, "DynMode", 1, 1);
+      for (modeIndex = 0; modeIndex < NUM_DYN_MODES; modeIndex++) {
+         /*
+          * Initialise the dynamic mode if it hasn't been used before.
+          */
+         if (!pVMWARE->dynModes[modeIndex]) {
+            pVMWARE->dynModes[modeIndex] = VMWAREAddDisplayMode(pScrn, "DynMode", 1, 1);
+         }
+
+         mode = pVMWARE->dynModes[modeIndex];
+         if (mode != pScrn->currentMode) {
+            break;
+         }
       }
-      mode = pVMWARE->dynMode1;
 
       mode->HDisplay = x;
       mode->VDisplay = y;