[PATCH] MdeModulePkg/NvmExpressDxe: fix error status override

[Heyi Guo <heyi.guo@linaro.org>]

Commit f6b139b added return status handling to PciIo->Mem.Write.
However, the second status handling will override EFI_DEVICE_ERROR
returned in this branch:

  //
  // Check the NVMe cmd execution result
  //
  if (Status != EFI_TIMEOUT) {
    if ((Cq->Sct == 0) && (Cq->Sc == 0)) {
      Status = EFI_SUCCESS;
    } else {
      Status = EFI_DEVICE_ERROR;
               ^^^^^^^^^^^^^^^^

Since PciIo->Mem.Write will probably return SUCCESS, it causes
NvmExpressPassThru to return SUCCESS even when DEVICE_ERROR occurs.
Callers of NvmExpressPassThru will then continue executing which may
cause further unexpected results, e.g. DiscoverAllNamespaces couldn't
break out the loop.

So we add a | (bit-or) to combine the return status together.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Heyi Guo <guoheyi@huawei.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
---
 MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressPassthru.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressPassthru.c b/MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressPassthru.c
index c33038f..2698b27 100644
--- a/MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressPassthru.c
+++ b/MdeModulePkg/Bus/Pci/NvmExpressDxe/NvmExpressPassthru.c
@@ -831,7 +831,7 @@ NvmExpressPassThru (
   }
 
   Data = ReadUnaligned32 ((UINT32*)&Private->CqHdbl[QueueId]);
-  Status = PciIo->Mem.Write (
+  Status |= PciIo->Mem.Write (
                PciIo,
                EfiPciIoWidthUint32,
                NVME_BAR,
-- 
2.7.2.windows.1