x86 / x64 CPUID en C #

En relación con mi otra pregunta , ayúdame a depurar “Se produjo una excepción no controlada del tipo ‘System.AccessViolationException’ en el Módulo desconocido. Información adicional: Intentó leer o escribir en la memoria protegida. Esto a menudo indica que otra memoria está dañada”. Al recorrer el código, todo funciona hasta la llamada real a del () y falla en esa línea.

Este código se basa en la muestra de este artículo y este código python que funciona en python. No puedo obtener el ejemplo del código como está para funcionar tampoco (la misma excepción), pero tengo la esperanza de que esté un poco desactualizado o algo así.

EDITAR: vea el historial de edición si le importa cómo llegamos aquí, que no es interesante.

Versión de trabajo finalizada:

public static class CpuID { public static byte[] Invoke(int level) { IntPtr codePointer = IntPtr.Zero; try { // compile byte[] codeBytes; if (IntPtr.Size == 4) { codeBytes = x86CodeBytes; } else { codeBytes = x64CodeBytes; } codePointer = VirtualAlloc( IntPtr.Zero, new UIntPtr((uint)codeBytes.Length), AllocationType.COMMIT | AllocationType.RESERVE, MemoryProtection.EXECUTE_READWRITE ); Marshal.Copy(codeBytes, 0, codePointer, codeBytes.Length); CpuIDDelegate cpuIdDelg = (CpuIDDelegate)Marshal.GetDelegateForFunctionPointer(codePointer, typeof(CpuIDDelegate)); // invoke GCHandle handle = default(GCHandle); var buffer = new byte[16]; try { handle = GCHandle.Alloc(buffer, GCHandleType.Pinned); cpuIdDelg(level, buffer); } finally { if (handle != default(GCHandle)) { handle.Free(); } } return buffer; } finally { if (codePointer != IntPtr.Zero) { VirtualFree(codePointer, 0, 0x8000); codePointer = IntPtr.Zero; } } } [UnmanagedFunctionPointerAttribute(CallingConvention.Cdecl)] private delegate void CpuIDDelegate(int level, byte[] buffer); [DllImport("kernel32.dll", SetLastError = true)] private static extern IntPtr VirtualAlloc(IntPtr lpAddress, UIntPtr dwSize, AllocationType flAllocationType, MemoryProtection flProtect); [DllImport("kernel32")] private static extern bool VirtualFree(IntPtr lpAddress, UInt32 dwSize, UInt32 dwFreeType); [Flags()] private enum AllocationType : uint { COMMIT = 0x1000, RESERVE = 0x2000, RESET = 0x80000, LARGE_PAGES = 0x20000000, PHYSICAL = 0x400000, TOP_DOWN = 0x100000, WRITE_WATCH = 0x200000 } [Flags()] private enum MemoryProtection : uint { EXECUTE = 0x10, EXECUTE_READ = 0x20, EXECUTE_READWRITE = 0x40, EXECUTE_WRITECOPY = 0x80, NOACCESS = 0x01, READONLY = 0x02, READWRITE = 0x04, WRITECOPY = 0x08, GUARD_Modifierflag = 0x100, NOCACHE_Modifierflag = 0x200, WRITECOMBINE_Modifierflag = 0x400 } // Basic ASM strategy -- // void x86CpuId(int level, byte* buffer) // { // eax = level // cpuid // buffer[0] = eax // buffer[4] = ebx // buffer[8] = ecx // buffer[12] = edx // } private readonly static byte[] x86CodeBytes = { 0x55, // push ebp 0x8B, 0xEC, // mov ebp,esp 0x53, // push ebx 0x57, // push edi 0x8B, 0x45, 0x08, // mov eax, dword ptr [ebp+8] (move level into eax) 0x0F, 0xA2, // cpuid 0x8B, 0x7D, 0x0C, // mov edi, dword ptr [ebp+12] (move address of buffer into edi) 0x89, 0x07, // mov dword ptr [edi+0], eax (write eax, ... to buffer) 0x89, 0x5F, 0x04, // mov dword ptr [edi+4], ebx 0x89, 0x4F, 0x08, // mov dword ptr [edi+8], ecx 0x89, 0x57, 0x0C, // mov dword ptr [edi+12],edx 0x5F, // pop edi 0x5B, // pop ebx 0x8B, 0xE5, // mov esp,ebp 0x5D, // pop ebp 0xc3 // ret }; private readonly static byte[] x64CodeBytes = { 0x53, // push rbx this gets clobbered by cpuid // rcx is level // rdx is buffer. // Need to save buffer elsewhere, cpuid overwrites rdx // Put buffer in r8, use r8 to reference buffer later. // Save rdx (buffer addy) to r8 0x49, 0x89, 0xd0, // mov r8, rdx // Move ecx (level) to eax to call cpuid, call cpuid 0x89, 0xc8, // mov eax, ecx 0x0F, 0xA2, // cpuid // Write eax et al to buffer 0x41, 0x89, 0x40, 0x00, // mov dword ptr [r8+0], eax 0x41, 0x89, 0x58, 0x04, // mov dword ptr [r8+4], ebx 0x41, 0x89, 0x48, 0x08, // mov dword ptr [r8+8], ecx 0x41, 0x89, 0x50, 0x0c, // mov dword ptr [r8+12], edx 0x5b, // pop rbx 0xc3 // ret }; } 

Tenga en cuenta que CPUID0 debe leerse en el orden correcto:

 //a twelve character ASCII string stored in EBX, EDX, ECX - in that order var cpuid0s = new string(ASCIIEncoding.ASCII.GetChars( cpuid0.Skip(4).Take(4).Concat( cpuid0.Skip(12).Take(4)).Concat( cpuid0.Skip(8).Take(4)).ToArray())); 

Estoy bastante seguro de que estás siendo bloqueado por DEP . Las x_CPUIDy_INSNS bytes x_CPUIDy_INSNS están en un segmento de memoria marcado como datos y no ejecutable.

EDITAR:

Dicho esto, obtuve una versión que comstack y ejecuta, pero no creo que tenga los valores correctos. Tal vez esto te ayude a seguir tu camino.

EDICION 2:

Creo que tengo los valores correctos regresando ahora. Siéntase libre de validar.

 namespace CPUID { using System; using System.Globalization; using System.Linq; using System.Reflection; using System.Runtime.InteropServices; using System.Text; internal static class Program { [Flags] private enum AllocationTypes : uint { Commit = 0x1000, Reserve = 0x2000, Reset = 0x80000, LargePages = 0x20000000, Physical = 0x400000, TopDown = 0x100000, WriteWatch = 0x200000 } [Flags] private enum MemoryProtections : uint { Execute = 0x10, ExecuteRead = 0x20, ExecuteReadWrite = 0x40, ExecuteWriteCopy = 0x80, NoAccess = 0x01, ReadOnly = 0x02, ReadWrite = 0x04, WriteCopy = 0x08, GuartModifierflag = 0x100, NoCacheModifierflag = 0x200, WriteCombineModifierflag = 0x400 } [Flags] private enum FreeTypes : uint { Decommit = 0x4000, Release = 0x8000 } [UnmanagedFunctionPointerAttribute(CallingConvention.Cdecl)] private unsafe delegate void CPUID0Delegate(byte* buffer); [UnmanagedFunctionPointerAttribute(CallingConvention.Cdecl)] private unsafe delegate void CPUID1Delegate(byte* buffer); private static void Main() { Console.WriteLine("CPUID0: {0}", string.Join(", ", CPUID0().Select(x => x.ToString("X2", CultureInfo.InvariantCulture)))); Console.WriteLine("CPUID0: {0}", new string(ASCIIEncoding.ASCII.GetChars(CPUID0()))); Console.WriteLine("CPUID1: {0}", string.Join(", ", CPUID1().Select(x => x.ToString("X2", CultureInfo.InvariantCulture)))); Console.ReadLine(); } private static unsafe byte[] CPUID0() { byte[] buffer = new byte[12]; if (IntPtr.Size == 4) { IntPtr p = NativeMethods.VirtualAlloc( IntPtr.Zero, new UIntPtr((uint)x86_CPUID0_INSNS.Length), AllocationTypes.Commit | AllocationTypes.Reserve, MemoryProtections.ExecuteReadWrite); try { Marshal.Copy(x86_CPUID0_INSNS, 0, p, x86_CPUID0_INSNS.Length); CPUID0Delegate del = (CPUID0Delegate)Marshal.GetDelegateForFunctionPointer(p, typeof(CPUID0Delegate)); fixed (byte* newBuffer = &buffer[0]) { del(newBuffer); } } finally { NativeMethods.VirtualFree(p, 0, FreeTypes.Release); } } else if (IntPtr.Size == 8) { IntPtr p = NativeMethods.VirtualAlloc( IntPtr.Zero, new UIntPtr((uint)x64_CPUID0_INSNS.Length), AllocationTypes.Commit | AllocationTypes.Reserve, MemoryProtections.ExecuteReadWrite); try { Marshal.Copy(x64_CPUID0_INSNS, 0, p, x64_CPUID0_INSNS.Length); CPUID0Delegate del = (CPUID0Delegate)Marshal.GetDelegateForFunctionPointer(p, typeof(CPUID0Delegate)); fixed (byte* newBuffer = &buffer[0]) { del(newBuffer); } } finally { NativeMethods.VirtualFree(p, 0, FreeTypes.Release); } } return buffer; } private static unsafe byte[] CPUID1() { byte[] buffer = new byte[12]; if (IntPtr.Size == 4) { IntPtr p = NativeMethods.VirtualAlloc( IntPtr.Zero, new UIntPtr((uint)x86_CPUID1_INSNS.Length), AllocationTypes.Commit | AllocationTypes.Reserve, MemoryProtections.ExecuteReadWrite); try { Marshal.Copy(x86_CPUID1_INSNS, 0, p, x86_CPUID1_INSNS.Length); CPUID1Delegate del = (CPUID1Delegate)Marshal.GetDelegateForFunctionPointer(p, typeof(CPUID1Delegate)); fixed (byte* newBuffer = &buffer[0]) { del(newBuffer); } } finally { NativeMethods.VirtualFree(p, 0, FreeTypes.Release); } } else if (IntPtr.Size == 8) { IntPtr p = NativeMethods.VirtualAlloc( IntPtr.Zero, new UIntPtr((uint)x64_CPUID1_INSNS.Length), AllocationTypes.Commit | AllocationTypes.Reserve, MemoryProtections.ExecuteReadWrite); try { Marshal.Copy(x64_CPUID1_INSNS, 0, p, x64_CPUID1_INSNS.Length); CPUID1Delegate del = (CPUID1Delegate)Marshal.GetDelegateForFunctionPointer(p, typeof(CPUID1Delegate)); fixed (byte* newBuffer = &buffer[0]) { del(newBuffer); } } finally { NativeMethods.VirtualFree(p, 0, FreeTypes.Release); } } return buffer; } private static class NativeMethods { [DllImport("kernel32.dll", SetLastError = true)] internal static extern IntPtr VirtualAlloc( IntPtr lpAddress, UIntPtr dwSize, AllocationTypes flAllocationType, MemoryProtections flProtect); [DllImport("kernel32")] [return: MarshalAs(UnmanagedType.Bool)] internal static extern bool VirtualFree( IntPtr lpAddress, uint dwSize, FreeTypes flFreeType); } #region ASM private static readonly byte[] x86_CPUID0_INSNS = new byte[] { 0x53, // push %ebx 0x31, 0xc0, // xor %eax,%eax 0x0f, 0xa2, // cpuid 0x8b, 0x44, 0x24, 0x08, // mov 0x8(%esp),%eax 0x89, 0x18, // mov %ebx,0x0(%eax) 0x89, 0x50, 0x04, // mov %edx,0x4(%eax) 0x89, 0x48, 0x08, // mov %ecx,0x8(%eax) 0x5b, // pop %ebx 0xc3 // ret }; private static readonly byte[] x86_CPUID1_INSNS = new byte[] { 0x53, // push %ebx 0x31, 0xc0, // xor %eax,%eax 0x40, // inc %eax 0x0f, 0xa2, // cpuid 0x5b, // pop %ebx 0xc3 // ret }; private static readonly byte[] x64_CPUID0_INSNS = new byte[] { 0x49, 0x89, 0xd8, // mov %rbx,%r8 0x49, 0x89, 0xc9, // mov %rcx,%r9 0x48, 0x31, 0xc0, // xor %rax,%rax 0x0f, 0xa2, // cpuid 0x4c, 0x89, 0xc8, // mov %r9,%rax 0x89, 0x18, // mov %ebx,0x0(%rax) 0x89, 0x50, 0x04, // mov %edx,0x4(%rax) 0x89, 0x48, 0x08, // mov %ecx,0x8(%rax) 0x4c, 0x89, 0xc3, // mov %r8,%rbx 0xc3 // retq }; private static readonly byte[] x64_CPUID1_INSNS = new byte[] { 0x53, // push %rbx 0x48, 0x31, 0xc0, // xor %rax,%rax 0x48, 0xff, 0xc0, // inc %rax 0x0f, 0xa2, // cpuid 0x5b, // pop %rbx 0xc3 // retq }; #endregion } } 

Decidí mejorar tu respuesta. Ya no es necesario comstackr inseguro, y solo necesita dos bloques de ensamblaje para poder leer cualquiera y todos los bloques de cpuid, porque solo escribe eax / ebx / ecx / edx en una matriz de bytes de 16 bytes.

 using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Reflection; using System.Runtime.InteropServices; namespace CpuID { public class CpuID : IDisposable { [UnmanagedFunctionPointerAttribute(CallingConvention.Cdecl)] public delegate void CpuIDDelegate(int level, byte[] buffer); [DllImport("kernel32.dll", SetLastError = true)] private static extern IntPtr VirtualAlloc( IntPtr lpAddress, UIntPtr dwSize, AllocationType flAllocationType, MemoryProtection flProtect ); [DllImport("kernel32")] private static extern bool VirtualFree( IntPtr lpAddress, UInt32 dwSize, UInt32 dwFreeType ); [Flags()] public enum AllocationType : uint { COMMIT = 0x1000, RESERVE = 0x2000, RESET = 0x80000, LARGE_PAGES = 0x20000000, PHYSICAL = 0x400000, TOP_DOWN = 0x100000, WRITE_WATCH = 0x200000 } [Flags()] public enum MemoryProtection : uint { EXECUTE = 0x10, EXECUTE_READ = 0x20, EXECUTE_READWRITE = 0x40, EXECUTE_WRITECOPY = 0x80, NOACCESS = 0x01, READONLY = 0x02, READWRITE = 0x04, WRITECOPY = 0x08, GUARD_Modifierflag = 0x100, NOCACHE_Modifierflag = 0x200, WRITECOMBINE_Modifierflag = 0x400 } private CpuIDDelegate cpuIdDelg; private IntPtr codePointer; // void x86CpuId(int level, byte* buffer) // { // eax = level // cpuid // buffer[0] = eax // buffer[4] = ebx // buffer[8] = ecx // buffer[12] = edx // } private byte[] x86CodeBytes = { 0x55, // push ebp 0x8B, 0xEC, // mov ebp,esp 0x53, // push ebx 0x57, // push edi 0x8B, 0x45, 0x08, // mov eax, dword ptr [ebp+8] (move level into eax) 0x0F, 0xA2, // cpuid 0x8B, 0x7D, 0x0C, // mov edi, dword ptr [ebp+12] (move address of buffer into edi) 0x89, 0x07, // mov dword ptr [edi+0], eax (write eax, ... to buffer) 0x89, 0x5F, 0x04, // mov dword ptr [edi+4], ebx 0x89, 0x4F, 0x08, // mov dword ptr [edi+8], ecx 0x89, 0x57, 0x0C, // mov dword ptr [edi+12],edx 0x5F, // pop edi 0x5B, // pop ebx 0x8B, 0xE5, // mov esp,ebp 0x5D, // pop ebp 0xc3 // ret }; private byte[] x64CodeBytes = { 0x53, // push rbx this gets clobbered by cpuid // rcx is level // rdx is buffer. // Need to save buffer elsewhere, cpuid overwrites rdx // Put buffer in r8, use r8 to reference buffer later. // Save rdx (buffer addy) to r8 0x49, 0x89, 0xd0, // mov r8, rdx // Move ecx (level) to eax to call cpuid, call cpuid 0x89, 0xc8, // mov eax, ecx 0x0F, 0xA2, // cpuid // Write eax et al to buffer 0x41, 0x89, 0x40, 0x00, // mov dword ptr [r8+0], eax 0x41, 0x89, 0x58, 0x04, // mov dword ptr [r8+4], ebx 0x41, 0x89, 0x48, 0x08, // mov dword ptr [r8+8], ecx 0x41, 0x89, 0x50, 0x0c, // mov dword ptr [r8+12], edx 0x5b, // pop rbx 0xc3 // ret }; public CpuID() { Compile(); } ~CpuID() { Dispose(false); } private void Compile() { byte[] codeBytes; if (IntPtr.Size == 4) { codeBytes = x86CodeBytes; } else { codeBytes = x64CodeBytes; } this.codePointer = VirtualAlloc( IntPtr.Zero, new UIntPtr((uint)codeBytes.Length), AllocationType.COMMIT | AllocationType.RESERVE, MemoryProtection.EXECUTE_READWRITE ); Marshal.Copy(codeBytes, 0, this.codePointer, codeBytes.Length); this.cpuIdDelg = (CpuIDDelegate)Marshal.GetDelegateForFunctionPointer(this.codePointer, typeof(CpuIDDelegate)); } public void Invoke(int level, byte[] buffer) { GCHandle handle = default(GCHandle); if (buffer.Length < 16) { throw new ArgumentException("buffer must be at least 16 bytes long"); } try { handle = GCHandle.Alloc(buffer, GCHandleType.Pinned); this.cpuIdDelg(level, buffer); } finally { if (handle != default(GCHandle)) { handle.Free(); } } } public void Dispose() { Dispose(true); } public void Dispose(bool disposing) { if (this.codePointer != IntPtr.Zero) { VirtualFree(this.codePointer, 0, 0x8000); this.codePointer = IntPtr.Zero; } } } } 

Tomé el código de @antiduh y lo refactoricé en un método estático, por lo que no hay que administrar el ciclo de vida del objeto. Esto es más lento porque el código ASM no se reutiliza entre las llamadas a Invoke (), pero el intercambio de velocidad por simplicidad tiene sentido para mi caso de uso. Esta nueva versión puede llamar a CPUID 1000 veces en 15 milisegundos en mi máquina.

Gracias por el maravilloso código chicos!

 public static class CpuID { public static byte[] Invoke(int level) { IntPtr codePointer = IntPtr.Zero; try { // compile byte[] codeBytes; if (IntPtr.Size == 4) { codeBytes = x86CodeBytes; } else { codeBytes = x64CodeBytes; } codePointer = VirtualAlloc( IntPtr.Zero, new UIntPtr((uint)codeBytes.Length), AllocationType.COMMIT | AllocationType.RESERVE, MemoryProtection.EXECUTE_READWRITE ); Marshal.Copy(codeBytes, 0, codePointer, codeBytes.Length); CpuIDDelegate cpuIdDelg = (CpuIDDelegate)Marshal.GetDelegateForFunctionPointer(codePointer, typeof(CpuIDDelegate)); // invoke GCHandle handle = default(GCHandle); var buffer = new byte[16]; try { handle = GCHandle.Alloc(buffer, GCHandleType.Pinned); cpuIdDelg(level, buffer); } finally { if (handle != default(GCHandle)) { handle.Free(); } } return buffer; } finally { if (codePointer != IntPtr.Zero) { VirtualFree(codePointer, 0, 0x8000); codePointer = IntPtr.Zero; } } } [UnmanagedFunctionPointerAttribute(CallingConvention.Cdecl)] private delegate void CpuIDDelegate(int level, byte[] buffer); [DllImport("kernel32.dll", SetLastError = true)] private static extern IntPtr VirtualAlloc(IntPtr lpAddress, UIntPtr dwSize, AllocationType flAllocationType, MemoryProtection flProtect); [DllImport("kernel32")] private static extern bool VirtualFree(IntPtr lpAddress, UInt32 dwSize, UInt32 dwFreeType); [Flags()] private enum AllocationType : uint { COMMIT = 0x1000, RESERVE = 0x2000, RESET = 0x80000, LARGE_PAGES = 0x20000000, PHYSICAL = 0x400000, TOP_DOWN = 0x100000, WRITE_WATCH = 0x200000 } [Flags()] private enum MemoryProtection : uint { EXECUTE = 0x10, EXECUTE_READ = 0x20, EXECUTE_READWRITE = 0x40, EXECUTE_WRITECOPY = 0x80, NOACCESS = 0x01, READONLY = 0x02, READWRITE = 0x04, WRITECOPY = 0x08, GUARD_Modifierflag = 0x100, NOCACHE_Modifierflag = 0x200, WRITECOMBINE_Modifierflag = 0x400 } // Basic ASM strategy -- // void x86CpuId(int level, byte* buffer) // { // eax = level // cpuid // buffer[0] = eax // buffer[4] = ebx // buffer[8] = ecx // buffer[12] = edx // } private readonly static byte[] x86CodeBytes = { 0x55, // push ebp 0x8B, 0xEC, // mov ebp,esp 0x53, // push ebx 0x57, // push edi 0x8B, 0x45, 0x08, // mov eax, dword ptr [ebp+8] (move level into eax) 0x0F, 0xA2, // cpuid 0x8B, 0x7D, 0x0C, // mov edi, dword ptr [ebp+12] (move address of buffer into edi) 0x89, 0x07, // mov dword ptr [edi+0], eax (write eax, ... to buffer) 0x89, 0x5F, 0x04, // mov dword ptr [edi+4], ebx 0x89, 0x4F, 0x08, // mov dword ptr [edi+8], ecx 0x89, 0x57, 0x0C, // mov dword ptr [edi+12],edx 0x5F, // pop edi 0x5B, // pop ebx 0x8B, 0xE5, // mov esp,ebp 0x5D, // pop ebp 0xc3 // ret }; private readonly static byte[] x64CodeBytes = { 0x53, // push rbx this gets clobbered by cpuid // rcx is level // rdx is buffer. // Need to save buffer elsewhere, cpuid overwrites rdx // Put buffer in r8, use r8 to reference buffer later. // Save rdx (buffer addy) to r8 0x49, 0x89, 0xd0, // mov r8, rdx // Move ecx (level) to eax to call cpuid, call cpuid 0x89, 0xc8, // mov eax, ecx 0x0F, 0xA2, // cpuid // Write eax et al to buffer 0x41, 0x89, 0x40, 0x00, // mov dword ptr [r8+0], eax 0x41, 0x89, 0x58, 0x04, // mov dword ptr [r8+4], ebx 0x41, 0x89, 0x48, 0x08, // mov dword ptr [r8+8], ecx 0x41, 0x89, 0x50, 0x0c, // mov dword ptr [r8+12], edx 0x5b, // pop rbx 0xc3 // ret }; } 

¿Puedo sugerir la siguiente página: http://devpinoy.org/blogs/cvega/archive/2006/04/07/2658.aspx

Esta página le mostrará el código fuente del ensamblado para CPUID, cómo comstackrlo en una DLL y cómo llamarlo desde C #.

Además, si necesita otros procedimientos de identificación de hardware, le sugiero esta página: http://www.codeproject.com/KB/system/GetHardwareInformation.aspx

Esta página muestra cómo obtener información como información de la placa base, información del disco duro, información de la CPU, información de la tarjeta de video, etc., etc.

Además, para obtener CPUID4, se necesita un argumento más. Aquí es cómo obtienes CPUID0, CPUID1, CPUID2, CPUID4.

 byte[] cpuid0 = Invoke(0, 0); byte[] cpuid1 = Invoke(1, 0); byte[] cpuid2 = Invoke(2, 0); List cpuid4L = new List(); for (int i = 0; true; i++) { byte[] cpuid4 = Invoke(4, (uint)i); if ( (cpuid4[0] & 0x0F) == 0) break; cpuid4L.Add(cpuid4); } private static byte[] Invoke(uint functionNum, uint ecx) { IntPtr codePointer = IntPtr.Zero; try { // Select a code byte[] codeBytes; if (IntPtr.Size == 4) codeBytes = x86CodeBytes; else codeBytes = x64CodeBytes; codePointer = NativeMethods.VirtualAlloc(IntPtr.Zero, new UIntPtr((uint)codeBytes.Length), MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE); Marshal.Copy(codeBytes, 0, codePointer, codeBytes.Length); CpuIdDelegate cpuIdDelg = (CpuIdDelegate)Marshal.GetDelegateForFunctionPointer(codePointer, typeof(CpuIdDelegate)); // Invoke the code GCHandle handle = default(GCHandle); var buffer = new byte[16]; try { handle = GCHandle.Alloc(buffer, GCHandleType.Pinned); cpuIdDelg(ecx, functionNum, buffer); // Run the assembly code. } finally { if (handle != default(GCHandle)) { handle.Free(); } } return buffer; } finally { if (codePointer != IntPtr.Zero) { NativeMethods.VirtualFree(codePointer, (UIntPtr) 0, MEM_RELEASE); codePointer = IntPtr.Zero; } } } private readonly static byte[] x86CodeBytes = { 0x55, 0x8B, 0xEC, 0x53, 0x57, 0x8B, 0x4D, 0x08, 0x8B, 0x45, 0x0C, 0x0F, 0xA2, 0x8B, 0x7D, 0x10, 0x89, 0x07, 0x89, 0x5F, 0x04, 0x89, 0x4F, 0x08, 0x89, 0x57, 0x0C, 0x5F, 0x5B, 0x8B, 0xE5, 0x5D, 0xc3 }; private readonly static byte[] x64CodeBytes = { 0x53, 0x89, 0xD0, 0x0F, 0xA2, 0x41, 0x89, 0x40, 0x00, 0x41, 0x89, 0x58, 0x04, 0x41, 0x89, 0x48, 0x08, 0x41, 0x89, 0x50, 0x0c, 0x5b, 0xc3 }; 

Gracias a @antiduh por su solución. Cambiaría la firma Invoke un poco para una mejor usabilidad de la siguiente manera, por lo que no es necesario asignar un obtener el resultado como un conjunto de registros

  // This is a modification to https://stackoverflow.com/a/7964376/725903 [UnmanagedFunctionPointerAttribute(CallingConvention.Cdecl)] private delegate void CpuIDDelegate(int level, IntPtr ptr); [StructLayout(LayoutKind.Sequential, Size = 16)] public struct CpuIdResult { public int Eax; public int Ebx; public int Ecx; public int Edx; } public CpuIdResult Invoke(int level) { CpuIdResult result; IntPtr buffer = Marshal.AllocHGlobal(16); try { this.cpuIdDelg(level, buffer); result = (CpuIdResult)Marshal.PtrToStructure(buffer, typeof(CpuIdResult)); } finally { Marshal.FreeHGlobal(buffer); } return result; }