Fix UCD retry loop size bug

There is a bug in the attemptDeviceOp code where an error during the
deviceOp function will overwrite the io_bufferLength value causing the
retry loop to fail permanently on subsequent retries.

Change-Id: Ib525e60e1c6cca2604a279cc595946a92cd4f94d
RTC: 205982
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/75243
Reviewed-by: Michael Baiocchi <mbaiocch@us.ibm.com>
Reviewed-by: Ilya Smirnov <ismirno@us.ibm.com>
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: Nicholas E. Bofferding <bofferdn@us.ibm.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/src/usr/isteps/ucd/updateUcdFlash.C b/src/usr/isteps/ucd/updateUcdFlash.C
index 5648a331f..267fb06fc 100644
--- a/src/usr/isteps/ucd/updateUcdFlash.C
+++ b/src/usr/isteps/ucd/updateUcdFlash.C
@@ -1282,14 +1282,22 @@ public:
         errlHndl_t pNonRetryableError = nullptr;
         errlHndl_t pRetryableError    = nullptr;
         errlHndl_t pUcdError          = nullptr;
+        size_t size = 0;
 
         for (uint8_t retry = 0; retry <= UCD_MAX_RETRIES; ++retry)
         {
+            // If an error occurs during the deviceOp then it's possible the
+            // size will be overwritten. So, create a local variable with the
+            // requested size. Regardless of success or failure the size
+            // returned from the final deviceOp will be written to
+            // io_bufferLength.
+            size = io_bufferLength;
+
             // Perform deviceOp
             pUcdError = performDeviceOp(i_opType,
                                     i_smbusOpType,
                                     io_buffer,
-                                    io_bufferLength,
+                                    size,
                                     i_cmd);
 
             if (   (pUcdError != nullptr)
@@ -1410,6 +1418,10 @@ public:
             }
         }
 
+        // Regardless of success or failure, update io_bufferLength with final
+        // size returned from performDeviceOp().
+        io_bufferLength = size;
+
         return pNonRetryableError;
     }