From 0088c6b8c0909f412d165485606a1ea709671f14 Mon Sep 17 00:00:00 2001
From: havahol <havard.heitlo.holm@sintef.no>
Date: Fri, 21 Aug 2026 09:30:13 +0000
Subject: [PATCH] fix bug when creating GpuSeqILU0 from GPU matrix

---
 opm/simulators/linalg/gpuistl/GpuSeqILU0.hpp | 9 +++------
 opm/simulators/linalg/gpuistl/GpuVector.cpp  | 4 ++++
 tests/gpuistl/test_GpuVector.cpp             | 7 +++++++
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/opm/simulators/linalg/gpuistl/GpuSeqILU0.hpp b/opm/simulators/linalg/gpuistl/GpuSeqILU0.hpp
index 7ac06bcae25..5e12e9ade62 100644
--- a/opm/simulators/linalg/gpuistl/GpuSeqILU0.hpp
+++ b/opm/simulators/linalg/gpuistl/GpuSeqILU0.hpp
@@ -187,17 +187,14 @@ template <typename T, typename std::enable_if_t<is_gpu_matrix_v<T>, int>>
 GpuSeqILU0<M, X, Y, l>::GpuSeqILU0(const M& A, field_type w)
     : m_underlyingMatrix(A)
     , m_w(w)
-    , m_LU(A.getNonZeroValues().data(),
-           A.getRowIndices().data(),
-           A.getColumnIndices().data(),
-           A.nonzeroes(),
-           A.blockSize(),
-           A.N())
+    , m_LU(A.getRowIndices(), A.getColumnIndices(), A.blockSize())
     , m_temporaryStorage(m_LU.N() * m_LU.blockSize())
     , m_descriptionL(detail::createLowerDiagonalDescription())
     , m_descriptionU(detail::createUpperDiagonalDescription())
     , m_cuSparseHandle(detail::CuSparseHandle::getInstance())
 {
+    m_LU.updateNonzeroValues(A);
+
     // Some sanity check
     OPM_ERROR_IF(A.N() != m_LU.N(),
                  fmt::format("CuSparse matrix not same size as DUNE matrix. {} vs {}.", m_LU.N(), A.N()));
diff --git a/opm/simulators/linalg/gpuistl/GpuVector.cpp b/opm/simulators/linalg/gpuistl/GpuVector.cpp
index b5d41d406de..8c4e53a6bd7 100644
--- a/opm/simulators/linalg/gpuistl/GpuVector.cpp
+++ b/opm/simulators/linalg/gpuistl/GpuVector.cpp
@@ -26,6 +26,7 @@
 #include <opm/simulators/linalg/gpuistl/detail/cublas_wrapper.hpp>
 #include <opm/simulators/linalg/gpuistl/detail/gpu_constants.hpp>
 #include <opm/simulators/linalg/gpuistl/detail/gpu_safe_call.hpp>
+#include <opm/simulators/linalg/gpuistl/detail/is_gpu_pointer.hpp>
 #include <opm/simulators/linalg/gpuistl/detail/vector_operations.hpp>
 
 namespace Opm::gpuistl
@@ -49,6 +50,9 @@ template <class T>
 GpuVector<T>::GpuVector(const T* dataOnHost, const size_t numberOfElements)
     : GpuVector(numberOfElements)
 {
+    if (detail::isGPUPointer(dataOnHost)) {
+        OPM_THROW(std::invalid_argument, "dataOnHost is a GPU pointer, use copy constructor instead");
+    }
 
     OPM_GPU_SAFE_CALL(cudaMemcpy(
         m_dataOnDevice, dataOnHost, detail::to_size_t(m_numberOfElements) * sizeof(T), cudaMemcpyHostToDevice));
diff --git a/tests/gpuistl/test_GpuVector.cpp b/tests/gpuistl/test_GpuVector.cpp
index 5eb704d2290..550a0bbff4a 100644
--- a/tests/gpuistl/test_GpuVector.cpp
+++ b/tests/gpuistl/test_GpuVector.cpp
@@ -64,6 +64,13 @@ BOOST_AUTO_TEST_CASE(TestCopyFromHostConstructor)
     BOOST_CHECK_EQUAL_COLLECTIONS(buffer.begin(), buffer.end(), data.begin(), data.end());
 }
 
+BOOST_AUTO_TEST_CASE(TestCopyFromHostConstructorWithGPUPointer)
+{
+    std::vector<double> data {{1, 2, 3, 4, 5, 6, 7}};
+    auto vectorOnGPU = Opm::gpuistl::GpuVector<double>(data.data(), data.size());
+    BOOST_CHECK_THROW(Opm::gpuistl::GpuVector<double>(vectorOnGPU.data(), data.size()), std::invalid_argument);
+}
+
 
 BOOST_AUTO_TEST_CASE(TestCopyFromHostFunction)
 {