MdeModulePkg/RamDiskDxe: Init list head before registering RamDisk protocol

REF:https://bugzilla.tianocore.org/show_bug.cgi?id=3483

This patch initializes the linked list RegisteredRamDisks in
RamDiskDxeEntryPoint before the registration of gEfiRamDiskProtocolGuid
with InstallMultipleProtocolInterfaces, allowing ramdisks to be created
via a callback installed with RegisterProtocolNotify as soon as the
protocol is registered.

Without this, calling RamDisk->Register() in the callback causes a crash:

ASSERT [RamDiskDxe] MdePkg/Library/BaseLib/LinkedList.c(75): List->ForwardLink != ((void *) 0)

Signed-off-by: Trammell Hudson <hudson@trmm.net>
Cc: Daniel Schaefer <daniel.schaefer@hpe.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Zhichao Gao <zhichao.gao@intel.com>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>

1 files changed, 6 insertions, 5 deletions

diff --git a/MdeModulePkg/Universal/Disk/RamDiskDxe/RamDiskDriver.c b/MdeModulePkg/Universal/Disk/RamDiskDxe/RamDiskDriver.c
index fcbf4f117d..13e2aed87c 100644
--- a/MdeModulePkg/Universal/Disk/RamDiskDxe/RamDiskDriver.c
+++ b/MdeModulePkg/Universal/Disk/RamDiskDxe/RamDiskDriver.c
@@ -155,6 +155,12 @@ RamDiskDxeEntryPoint (
   }

 

   //

+  // Initialize the list of registered RAM disks maintained by the driver

+  // before installing the protocol

+  //

+  InitializeListHead (&RegisteredRamDisks);

+

+  //

   // Install the EFI_RAM_DISK_PROTOCOL and RAM disk private data onto a

   // new handle

   //

@@ -170,11 +176,6 @@ RamDiskDxeEntryPoint (
     goto ErrorExit;

   }

 

-  //

-  // Initialize the list of registered RAM disks maintained by the driver

-  //

-  InitializeListHead (&RegisteredRamDisks);

-

   Status = EfiCreateEventReadyToBootEx (

              TPL_CALLBACK,

              RamDiskAcpiCheck,