diff --git a/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenTestGenerated.java b/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenTestGenerated.java
index 77969089feb..836d5ffc8e0 100644
--- a/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenTestGenerated.java
+++ b/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenTestGenerated.java
@@ -45042,6 +45042,12 @@ public class FirLightTreeBlackBoxCodegenTestGenerated extends AbstractFirLightTr
                 runTest("compiler/testData/codegen/box/reflection/callBy/jvmStaticInObject.kt");
             }
 
+            @Test
+            @TestMetadata("kt61304.kt")
+            public void testKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/kt61304.kt");
+            }
+
             @Test
             @TestMetadata("manyArgumentsNoneDefaultConstructor.kt")
             public void testManyArgumentsNoneDefaultConstructor() throws Exception {
@@ -45078,6 +45084,12 @@ public class FirLightTreeBlackBoxCodegenTestGenerated extends AbstractFirLightTr
                 runTest("compiler/testData/codegen/box/reflection/callBy/mfvcFunctionsAndConstructors.kt");
             }
 
+            @Test
+            @TestMetadata("mfvcKt61304.kt")
+            public void testMfvcKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt");
+            }
+
             @Test
             @TestMetadata("mfvcMembers.kt")
             public void testMfvcMembers() throws Exception {
diff --git a/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenWithIrFakeOverrideGeneratorTestGenerated.java b/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenWithIrFakeOverrideGeneratorTestGenerated.java
index c7a55742b3b..8091c360b18 100644
--- a/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenWithIrFakeOverrideGeneratorTestGenerated.java
+++ b/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirLightTreeBlackBoxCodegenWithIrFakeOverrideGeneratorTestGenerated.java
@@ -45042,6 +45042,12 @@ public class FirLightTreeBlackBoxCodegenWithIrFakeOverrideGeneratorTestGenerated
                 runTest("compiler/testData/codegen/box/reflection/callBy/jvmStaticInObject.kt");
             }
 
+            @Test
+            @TestMetadata("kt61304.kt")
+            public void testKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/kt61304.kt");
+            }
+
             @Test
             @TestMetadata("manyArgumentsNoneDefaultConstructor.kt")
             public void testManyArgumentsNoneDefaultConstructor() throws Exception {
@@ -45078,6 +45084,12 @@ public class FirLightTreeBlackBoxCodegenWithIrFakeOverrideGeneratorTestGenerated
                 runTest("compiler/testData/codegen/box/reflection/callBy/mfvcFunctionsAndConstructors.kt");
             }
 
+            @Test
+            @TestMetadata("mfvcKt61304.kt")
+            public void testMfvcKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt");
+            }
+
             @Test
             @TestMetadata("mfvcMembers.kt")
             public void testMfvcMembers() throws Exception {
diff --git a/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirPsiBlackBoxCodegenTestGenerated.java b/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirPsiBlackBoxCodegenTestGenerated.java
index 94683f0720d..10cb55ee4a0 100644
--- a/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirPsiBlackBoxCodegenTestGenerated.java
+++ b/compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirPsiBlackBoxCodegenTestGenerated.java
@@ -45042,6 +45042,12 @@ public class FirPsiBlackBoxCodegenTestGenerated extends AbstractFirPsiBlackBoxCo
                 runTest("compiler/testData/codegen/box/reflection/callBy/jvmStaticInObject.kt");
             }
 
+            @Test
+            @TestMetadata("kt61304.kt")
+            public void testKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/kt61304.kt");
+            }
+
             @Test
             @TestMetadata("manyArgumentsNoneDefaultConstructor.kt")
             public void testManyArgumentsNoneDefaultConstructor() throws Exception {
@@ -45078,6 +45084,12 @@ public class FirPsiBlackBoxCodegenTestGenerated extends AbstractFirPsiBlackBoxCo
                 runTest("compiler/testData/codegen/box/reflection/callBy/mfvcFunctionsAndConstructors.kt");
             }
 
+            @Test
+            @TestMetadata("mfvcKt61304.kt")
+            public void testMfvcKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt");
+            }
+
             @Test
             @TestMetadata("mfvcMembers.kt")
             public void testMfvcMembers() throws Exception {
diff --git a/compiler/testData/codegen/box/reflection/callBy/kt61304.kt b/compiler/testData/codegen/box/reflection/callBy/kt61304.kt
new file mode 100644
index 00000000000..d9ca339eb0e
--- /dev/null
+++ b/compiler/testData/codegen/box/reflection/callBy/kt61304.kt
@@ -0,0 +1,81 @@
+// TARGET_BACKEND: JVM
+// WITH_REFLECT
+
+import kotlin.reflect.full.instanceParameter
+import kotlin.reflect.full.memberFunctions
+
+data class DataCopyBug(
+    val f01: Int = 0,
+    val f02: Int = 0,
+    val f03: Int = 0,
+    val f04: Int = 0,
+    val f05: Int = 0,
+    val f06: Int = 0,
+    val f07: Int = 0,
+    val f08: Int = 0,
+    val f09: Int = 0,
+    val f10: Int = 0,
+    val f11: Int = 0,
+    val f12: Int = 0,
+    val f13: Int = 0,
+    val f14: Int = 0,
+    val f15: Int = 0,
+    val f16: Int = 0,
+    val f17: Int = 0,
+    val f18: Int = 0,
+    val f19: Int = 0,
+    val f20: Int = 0,
+    val f21: Int = 0,
+    val f22: Int = 0,
+    val f23: Int = 0,
+    val f24: Int = 0,
+    val f25: Int = 0,
+    val f26: Int = 0,
+    val f27: Int = 0,
+    val f28: Int = 0,
+    val f29: Int = 0,
+    val f30: Int = 0,
+    val f31: Int = 0,
+    val f32: Int = 0,
+    val f33: Int = 0,
+    val f34: Int = 0,
+    val f35: Int = 0,
+    val f36: Int = 0,
+    val f37: Int = 0,
+    val f38: Int = 0,
+    val f39: Int = 0,
+    val f40: Int = 0,
+    val f41: Int = 0,
+    val f42: String = "Fail",
+    val f43: Int = 0,
+    val f44: Int = 0,
+    val f45: Int = 0,
+    val f46: Int = 0,
+    val f47: Int = 0,
+    val f48: Int = 0,
+    val f49: Int = 0,
+    val f50: Int = 0,
+    val f51: Int = 0,
+    val f52: Int = 0,
+    val f53: Int = 0,
+    val f54: Int = 0,
+    val f55: Int = 0,
+    val f56: Int = 0,
+    val f57: Int = 0,
+    val f58: Int = 0,
+    val f59: Int = 0,
+    val f60: Int = 0,
+    val f61: Int = 0,
+    val f62: Int = 0,
+    val f63: Int = 0,
+    val f64: Int = 0,
+)
+
+fun box(): String {
+    val copyFun = DataCopyBug::class.memberFunctions.single { it.name == "copy" }
+    val result = copyFun.callBy(mapOf(
+        copyFun.instanceParameter!! to DataCopyBug(),
+        copyFun.parameters.single { it.name == "f42" } to "OK",
+    ))
+    return (result as DataCopyBug).f42
+}
diff --git a/compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt b/compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt
new file mode 100644
index 00000000000..ab0e308054b
--- /dev/null
+++ b/compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt
@@ -0,0 +1,36 @@
+// TARGET_BACKEND: JVM_IR
+// WITH_REFLECT
+// LANGUAGE: +ValueClasses
+
+import kotlin.reflect.full.instanceParameter
+import kotlin.reflect.full.memberFunctions
+
+@JvmInline
+value class S2(val x: Int, val y: Int)
+@JvmInline
+value class S4(val x: S2, val y: S2)
+@JvmInline
+value class S8(val x: S4, val y: S4)
+@JvmInline
+value class S16(val x: S8, val y: S8)
+@JvmInline
+value class S32(val x: S16, val y: S16)
+@JvmInline
+value class S64(val x: S32, val y: S32)
+
+data class D(val s: S64 = createS64())
+
+fun createS64(): S64 {
+    val s2 = S2(0, 0)
+    val s4 = S4(s2, s2)
+    val s8 = S8(s4, s4)
+    val s16 = S16(s8, s8)
+    val s32 = S32(s16, s16)
+    return S64(s32, s32)
+}
+
+fun box(): String {
+    val copyFun = D::class.memberFunctions.single { it.name == "copy" }
+    copyFun.callBy(mapOf(copyFun.instanceParameter!! to D()))
+    return "OK"
+}
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/BlackBoxCodegenTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/BlackBoxCodegenTestGenerated.java
index 53cdcd5ef5a..5f6db8a0e8b 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/BlackBoxCodegenTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/BlackBoxCodegenTestGenerated.java
@@ -42324,6 +42324,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
                 runTest("compiler/testData/codegen/box/reflection/callBy/jvmStaticInObject.kt");
             }
 
+            @Test
+            @TestMetadata("kt61304.kt")
+            public void testKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/kt61304.kt");
+            }
+
             @Test
             @TestMetadata("manyArgumentsNoneDefaultConstructor.kt")
             public void testManyArgumentsNoneDefaultConstructor() throws Exception {
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java
index 4912e3d3f1f..6c08609a108 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java
@@ -45042,6 +45042,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 runTest("compiler/testData/codegen/box/reflection/callBy/jvmStaticInObject.kt");
             }
 
+            @Test
+            @TestMetadata("kt61304.kt")
+            public void testKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/kt61304.kt");
+            }
+
             @Test
             @TestMetadata("manyArgumentsNoneDefaultConstructor.kt")
             public void testManyArgumentsNoneDefaultConstructor() throws Exception {
@@ -45078,6 +45084,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
                 runTest("compiler/testData/codegen/box/reflection/callBy/mfvcFunctionsAndConstructors.kt");
             }
 
+            @Test
+            @TestMetadata("mfvcKt61304.kt")
+            public void testMfvcKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt");
+            }
+
             @Test
             @TestMetadata("mfvcMembers.kt")
             public void testMfvcMembers() throws Exception {
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenWithIrInlinerTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenWithIrInlinerTestGenerated.java
index 4a864c33bc7..dc2414a7e11 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenWithIrInlinerTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenWithIrInlinerTestGenerated.java
@@ -45042,6 +45042,12 @@ public class IrBlackBoxCodegenWithIrInlinerTestGenerated extends AbstractIrBlack
                 runTest("compiler/testData/codegen/box/reflection/callBy/jvmStaticInObject.kt");
             }
 
+            @Test
+            @TestMetadata("kt61304.kt")
+            public void testKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/kt61304.kt");
+            }
+
             @Test
             @TestMetadata("manyArgumentsNoneDefaultConstructor.kt")
             public void testManyArgumentsNoneDefaultConstructor() throws Exception {
@@ -45078,6 +45084,12 @@ public class IrBlackBoxCodegenWithIrInlinerTestGenerated extends AbstractIrBlack
                 runTest("compiler/testData/codegen/box/reflection/callBy/mfvcFunctionsAndConstructors.kt");
             }
 
+            @Test
+            @TestMetadata("mfvcKt61304.kt")
+            public void testMfvcKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt");
+            }
+
             @Test
             @TestMetadata("mfvcMembers.kt")
             public void testMfvcMembers() throws Exception {
diff --git a/compiler/tests-gen/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java b/compiler/tests-gen/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java
index 3bb411a66f2..08e32ae4648 100644
--- a/compiler/tests-gen/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java
+++ b/compiler/tests-gen/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java
@@ -35784,6 +35784,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
                 runTest("compiler/testData/codegen/box/reflection/callBy/jvmStaticInObject.kt");
             }
 
+            @TestMetadata("kt61304.kt")
+            public void testKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/kt61304.kt");
+            }
+
             @TestMetadata("manyArgumentsNoneDefaultConstructor.kt")
             public void testManyArgumentsNoneDefaultConstructor() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/callBy/manyArgumentsNoneDefaultConstructor.kt");
@@ -35814,6 +35819,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
                 runTest("compiler/testData/codegen/box/reflection/callBy/mfvcFunctionsAndConstructors.kt");
             }
 
+            @TestMetadata("mfvcKt61304.kt")
+            public void testMfvcKt61304() throws Exception {
+                runTest("compiler/testData/codegen/box/reflection/callBy/mfvcKt61304.kt");
+            }
+
             @TestMetadata("mfvcMembers.kt")
             public void testMfvcMembers() throws Exception {
                 runTest("compiler/testData/codegen/box/reflection/callBy/mfvcMembers.kt");
diff --git a/core/reflection.jvm/src/kotlin/reflect/jvm/internal/KCallableImpl.kt b/core/reflection.jvm/src/kotlin/reflect/jvm/internal/KCallableImpl.kt
index a6162dc5a1e..2e65d29a1b9 100644
--- a/core/reflection.jvm/src/kotlin/reflect/jvm/internal/KCallableImpl.kt
+++ b/core/reflection.jvm/src/kotlin/reflect/jvm/internal/KCallableImpl.kt
@@ -113,9 +113,16 @@ internal abstract class KCallableImpl<out R> : KCallable<R>, KTypeParameterOwner
     }
 
     private val _absentArguments = ReflectProperties.lazySoft {
+        val parameters = parameters
         val parameterSize = parameters.size + (if (isSuspend) 1 else 0)
         val flattenedParametersSize =
-            if (parametersNeedMFVCFlattening.value) parameters.sumOf { getParameterTypeSize(it) } else parameters.size
+            if (parametersNeedMFVCFlattening.value) {
+                parameters.sumOf {
+                    if (it.kind == KParameter.Kind.VALUE) getParameterTypeSize(it) else 0
+                }
+            } else {
+                parameters.count { it.kind == KParameter.Kind.VALUE }
+            }
         val maskSize = (flattenedParametersSize + Integer.SIZE - 1) / Integer.SIZE
 
         // Array containing the actual function arguments, masks, and +1 for DefaultConstructorMarker or MethodHandle.