Re: GPLPV Drivers 0.9.11-pre4 hang during boot - WindowsXP Pro SP2

[Wayne Gong <wayne.gong@oracle.com>]

Hi James,

I meet this problem before but not in the same scenario.
I use WinPv driver WDF version and attach a lot of vbd and vif device, 
such as 4 disks and 8 NICs. After WinPv driver install correctly, reboot 
the vm. Vm cannot reboot correctly every times. And the debug log is 
very similar as Sandro provided. I change the backend bit width detect 
code as follow. In my test box, WinPv driver works ok till now. Please 
have a try if you are interested in it.


+XenVbd_TestBitWidth(PXENVBD_DEVICE_DATA DeviceData, PXENVBD_TARGET_DATA TargetData)
+{
+  blkif_request_t *req;
+  ULONG i;
+  int notify;  
+  
+  KdPrint((__DRIVER_NAME " --> XenVbd_TestBitWidth\n"));
+    req = RING_GET_REQUEST(&TargetData->Ring, TargetData->Ring.req_prod_pvt);
+	req->id = 0;
+	KdPrint((__DRIVER_NAME "    req id : %d\n",req->id));
+    req->operation = 0xff;
+    req->nr_segments = 0;
+    for (i = 0; i < req->nr_segments; i++)
+    {
+      req->seg[i].gref = 0xffffffff;
+      req->seg[i].first_sect = 0xff;
+      req->seg[i].last_sect = 0xff;
+    }
+    TargetData->Ring.req_prod_pvt++;
+
+    RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&TargetData->Ring, notify);
+    KdPrint((__DRIVER_NAME "     1st notify: %d\n", notify));
+    if (notify)
+      DeviceData->XenDeviceData->XenInterface.EvtChn_Notify(
+        DeviceData->XenDeviceData->XenInterface.InterfaceHeader.Context,
+        TargetData->EventChannel);
+    KeMemoryBarrier();
+        
+    req = RING_GET_REQUEST(&TargetData->Ring, TargetData->Ring.req_prod_pvt);
+	req->id = 1;
+	KdPrint((__DRIVER_NAME "     req id : %d\n",req->id));
+    req->operation = 0xff;
+    req->nr_segments = 0;
+    for (i = 0; i < req->nr_segments; i++)
+    {
+      req->seg[i].gref = 0xffffffff;
+      req->seg[i].first_sect = 0xff;
+      req->seg[i].last_sect = 0xff;
+    }
+    TargetData->Ring.req_prod_pvt++;
+
+    RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(&TargetData->Ring, notify);
+    KdPrint((__DRIVER_NAME "     2nd notify: %d\n", notify));
+    if (notify)
+      DeviceData->XenDeviceData->XenInterface.EvtChn_Notify(
+        DeviceData->XenDeviceData->XenInterface.InterfaceHeader.Context,
+        TargetData->EventChannel);
+    KeMemoryBarrier();
+  KdPrint((__DRIVER_NAME " <-- XenVbd_TestBitWidth\n"));
+    return;
+}