OvmfPkg: XenPvBlkDxe: handle empty cdrom drives

[mirror_edk2.git] / OvmfPkg / XenPvBlkDxe / BlockFront.c

diff --git a/OvmfPkg/XenPvBlkDxe/BlockFront.c b/OvmfPkg/XenPvBlkDxe/BlockFront.c
index 256ac55f251538f0a089b4cfc029757a5f83f2ba..d07e980990562ed56c39b901abdeee2594373433 100644 (file)
--- a/OvmfPkg/XenPvBlkDxe/BlockFront.c
+++ b/OvmfPkg/XenPvBlkDxe/BlockFront.c
@@ -169,6 +169,7 @@ XenPvBlockFrontInitialization (
   XEN_BLOCK_FRONT_DEVICE *Dev;\r
   XenbusState State;\r
   UINT64 Value;\r
+  CHAR8 *Params;\r
 \r
   ASSERT (NodeName != NULL);\r
 \r
@@ -186,6 +187,20 @@ XenPvBlockFrontInitialization (
   }\r
   FreePool (DeviceType);\r
 \r
+  if (Dev->MediaInfo.CdRom) {\r
+    Status = XenBusIo->XsBackendRead (XenBusIo, XST_NIL, "params", (VOID**)&Params);\r
+    if (Status != XENSTORE_STATUS_SUCCESS) {\r
+      DEBUG ((EFI_D_ERROR, "%a: Failed to read params (%d)\n", __FUNCTION__, Status));\r
+      goto Error;\r
+    }\r
+    if (AsciiStrLen (Params) == 0 || AsciiStrCmp (Params, "aio:") == 0) {\r
+      FreePool (Params);\r
+      DEBUG ((EFI_D_INFO, "%a: Empty cdrom\n", __FUNCTION__));\r
+      goto Error;\r
+    }\r
+    FreePool (Params);\r
+  }\r
+\r
   Status = XenBusReadUint64 (XenBusIo, "backend-id", FALSE, &Value);\r
   if (Status != XENSTORE_STATUS_SUCCESS || Value > MAX_UINT16) {\r
     DEBUG ((EFI_D_ERROR, "XenPvBlk: Failed to get backend-id (%d)\n",\r