diff --git a/internal/ceres/schur_complement_solver.cc b/internal/ceres/schur_complement_solver.cc
index 1a1becb69..16470fd8a 100644
--- a/internal/ceres/schur_complement_solver.cc
+++ b/internal/ceres/schur_complement_solver.cc
@@ -337,6 +337,9 @@ LinearSolver::Summary SparseSchurComplementSolver::SolveReducedLinearSystem(
     lhs->set_storage_type(CompressedRowSparseMatrix::LOWER_TRIANGULAR);
   }
 
+  *lhs->mutable_col_blocks() = blocks_;
+  *lhs->mutable_row_blocks() = blocks_;
+
   summary.num_iterations = 1;
   summary.termination_type = sparse_cholesky_->FactorAndSolve(
       lhs.get(), rhs(), solution, &summary.message);
diff --git a/internal/ceres/trust_region_preprocessor.cc b/internal/ceres/trust_region_preprocessor.cc
index 4020e4ca1..d3f912cdd 100644
--- a/internal/ceres/trust_region_preprocessor.cc
+++ b/internal/ceres/trust_region_preprocessor.cc
@@ -121,6 +121,7 @@ bool ReorderProgram(PreprocessedProblem* pp) {
         &pp->error);
   }
 
+
   if (options.linear_solver_type == SPARSE_NORMAL_CHOLESKY &&
       !options.dynamic_sparsity) {
     return ReorderProgramForSparseNormalCholesky(
@@ -192,28 +193,40 @@ bool SetupLinearSolver(PreprocessedProblem* pp) {
       options.use_explicit_schur_complement;
   pp->linear_solver_options.dynamic_sparsity = options.dynamic_sparsity;
   pp->linear_solver_options.num_threads = options.num_linear_solver_threads;
-
-  // Ignore user's postordering preferences and force it to be true if
-  // cholmod_camd is not available. This ensures that the linear
-  // solver does not assume that a fill-reducing pre-ordering has been
-  // done.
   pp->linear_solver_options.use_postordering = options.use_postordering;
-  if (options.linear_solver_type == SPARSE_SCHUR &&
-      options.sparse_linear_algebra_library_type == SUITE_SPARSE &&
-      !SuiteSparse::IsConstrainedApproximateMinimumDegreeOrderingAvailable()) {
-    pp->linear_solver_options.use_postordering = true;
-  }
 
-  OrderingToGroupSizes(options.linear_solver_ordering.get(),
-                       &pp->linear_solver_options.elimination_groups);
+  if (IsSchurType(pp->linear_solver_options.type)) {
+    OrderingToGroupSizes(options.linear_solver_ordering.get(),
+                         &pp->linear_solver_options.elimination_groups);
 
-  // Schur type solvers expect at least two elimination groups. If
-  // there is only one elimination group, then it is guaranteed that
-  // this group only contains e_blocks. Thus we add a dummy
-  // elimination group with zero blocks in it.
-  if (IsSchurType(pp->linear_solver_options.type) &&
-      pp->linear_solver_options.elimination_groups.size() == 1) {
-    pp->linear_solver_options.elimination_groups.push_back(0);
+    // Schur type solvers expect at least two elimination groups. If
+    // there is only one elimination group, then it is guaranteed that
+    // this group only contains e_blocks. Thus we add a dummy
+    // elimination group with zero blocks in it.
+    if (pp->linear_solver_options.elimination_groups.size() == 1) {
+      pp->linear_solver_options.elimination_groups.push_back(0);
+    }
+
+    if (options.linear_solver_type == SPARSE_SCHUR) {
+      // When using SPARSE_SCHUR, we ignore the user's postordering
+      // preferences in certain cases.
+      //
+      // 1. SUITE_SPARSE is the sparse linear algebra library requested
+      //    but cholmod_camd is not available.
+      // 2. CX_SPARSE is the sparse linear algebra library requested.
+      //
+      // This ensures that the linear solver does not assume that a
+      // fill-reducing pre-ordering has been done.
+      //
+      // TODO(sameeragarwal): Implement the reordering of parameter
+      // blocks for CX_SPARSE.
+      if ((options.sparse_linear_algebra_library_type == SUITE_SPARSE &&
+           !SuiteSparse::
+           IsConstrainedApproximateMinimumDegreeOrderingAvailable()) ||
+          (options.sparse_linear_algebra_library_type == CX_SPARSE)) {
+        pp->linear_solver_options.use_postordering = true;
+      }
+    }
   }
 
   pp->linear_solver.reset(LinearSolver::Create(pp->linear_solver_options));