Print guest stack trace on invalid memory access (#1407)

* Print guest stack trace on invalid memory access * Improve XML docs
author: gdkchan <gab.dark.100@gmail.com> 2020-07-30 10:16:41 -0300
committer: GitHub <noreply@github.com> 2020-07-30 23:16:41 +1000
commit: 57bb0abda3dc277dc7575250fdb080edb83abcbc (patch)
tree: 21fd7e3cdea856037c4794e2de0b68ff80be4b63 /Ryujinx.Cpu
parent: 636542d817b3403ae44b46a48a67cedc0c7b42c5 (diff)
2 files changed, 86 insertions, 35 deletions
diff --git a/Ryujinx.Cpu/InvalidAccessHandler.cs b/Ryujinx.Cpu/InvalidAccessHandler.cs
new file mode 100644
index 00000000..0d3d387d
--- /dev/null
+++ b/Ryujinx.Cpu/InvalidAccessHandler.cs
@@ -0,0 +1,9 @@
+namespace Ryujinx.Cpu
+{
+    /// <summary>
+    /// Function that handles a invalid memory access from the emulated CPU.
+    /// </summary>
+    /// <param name="va">Virtual address of the invalid region that is being accessed</param>
+    /// <returns>True if the invalid access should be ignored, false otherwise</returns>
+    public delegate bool InvalidAccessHandler(ulong va);
+}
diff --git a/Ryujinx.Cpu/MemoryManager.cs b/Ryujinx.Cpu/MemoryManager.cs
index 211a8c0d..31357508 100644
--- a/Ryujinx.Cpu/MemoryManager.cs
+++ b/Ryujinx.Cpu/MemoryManager.cs
@@ -18,6 +18,11 @@ namespace Ryujinx.Cpu
 
         private const int PteSize = 8;
 
+        private readonly InvalidAccessHandler _invalidAccessHandler;
+
+        /// <summary>
+        /// Address space width in bits.
+        /// </summary>
         public int AddressSpaceBits { get; }
 
         private readonly ulong _addressSpaceSize;
@@ -25,6 +30,9 @@ namespace Ryujinx.Cpu
         private readonly MemoryBlock _backingMemory;
         private readonly MemoryBlock _pageTable;
 
+        /// <summary>
+        /// Page table base pointer.
+        /// </summary>
         public IntPtr PageTablePointer => _pageTable.Pointer;
 
         /// <summary>
@@ -32,8 +40,11 @@ namespace Ryujinx.Cpu
         /// </summary>
         /// <param name="backingMemory">Physical backing memory where virtual memory will be mapped to</param>
         /// <param name="addressSpaceSize">Size of the address space</param>
-        public MemoryManager(MemoryBlock backingMemory, ulong addressSpaceSize)
+        /// <param name="invalidAccessHandler">Optional function to handle invalid memory accesses</param>
+        public MemoryManager(MemoryBlock backingMemory, ulong addressSpaceSize, InvalidAccessHandler invalidAccessHandler = null)
         {
+            _invalidAccessHandler = invalidAccessHandler;
+
             ulong asSize = PageSize;
             int asBits = PageBits;
 
@@ -92,6 +103,7 @@ namespace Ryujinx.Cpu
         /// <typeparam name="T">Type of the data being read</typeparam>
         /// <param name="va">Virtual address of the data in memory</param>
         /// <returns>The data</returns>
+        /// <exception cref="InvalidMemoryRegionException">Throw for unhandled invalid or unmapped memory accesses</exception>
         public T Read<T>(ulong va) where T : unmanaged
         {
             return MemoryMarshal.Cast<byte, T>(GetSpan(va, Unsafe.SizeOf<T>()))[0];
@@ -102,6 +114,7 @@ namespace Ryujinx.Cpu
         /// </summary>
         /// <param name="va">Virtual address of the data in memory</param>
         /// <param name="data">Span to store the data being read into</param>
+        /// <exception cref="InvalidMemoryRegionException">Throw for unhandled invalid or unmapped memory accesses</exception>
         public void Read(ulong va, Span<byte> data)
         {
             ReadImpl(va, data);
@@ -113,6 +126,7 @@ namespace Ryujinx.Cpu
         /// <typeparam name="T">Type of the data being written</typeparam>
         /// <param name="va">Virtual address to write the data into</param>
         /// <param name="value">Data to be written</param>
+        /// <exception cref="InvalidMemoryRegionException">Throw for unhandled invalid or unmapped memory accesses</exception>
         public void Write<T>(ulong va, T value) where T : unmanaged
         {
             Write(va, MemoryMarshal.Cast<T, byte>(MemoryMarshal.CreateSpan(ref value, 1)));
@@ -123,6 +137,7 @@ namespace Ryujinx.Cpu
         /// </summary>
         /// <param name="va">Virtual address to write the data into</param>
         /// <param name="data">Data to be written</param>
+        /// <exception cref="InvalidMemoryRegionException">Throw for unhandled invalid or unmapped memory accesses</exception>
         public void Write(ulong va, ReadOnlySpan<byte> data)
         {
             if (data.Length == 0)
@@ -130,34 +145,44 @@ namespace Ryujinx.Cpu
                 return;
             }
 
-            MarkRegionAsModified(va, (ulong)data.Length);
-
-            if (IsContiguous(va, data.Length))
+            try
             {
-                data.CopyTo(_backingMemory.GetSpan(GetPhysicalAddressInternal(va), data.Length));
-            }
-            else
-            {
-                int offset = 0, size;
+                MarkRegionAsModified(va, (ulong)data.Length);
 
-                if ((va & PageMask) != 0)
+                if (IsContiguousAndMapped(va, data.Length))
                 {
-                    ulong pa = GetPhysicalAddressInternal(va);
+                    data.CopyTo(_backingMemory.GetSpan(GetPhysicalAddressInternal(va), data.Length));
+                }
+                else
+                {
+                    int offset = 0, size;
 
-                    size = Math.Min(data.Length, PageSize - (int)(va & PageMask));
+                    if ((va & PageMask) != 0)
+                    {
+                        ulong pa = GetPhysicalAddressInternal(va);
 
-                    data.Slice(0, size).CopyTo(_backingMemory.GetSpan(pa, size));
+                        size = Math.Min(data.Length, PageSize - (int)(va & PageMask));
 
-                    offset += size;
-                }
+                        data.Slice(0, size).CopyTo(_backingMemory.GetSpan(pa, size));
 
-                for (; offset < data.Length; offset += size)
-                {
-                    ulong pa = GetPhysicalAddressInternal(va + (ulong)offset);
+                        offset += size;
+                    }
 
-                    size = Math.Min(data.Length - offset, PageSize);
+                    for (; offset < data.Length; offset += size)
+                    {
+                        ulong pa = GetPhysicalAddressInternal(va + (ulong)offset);
+
+                        size = Math.Min(data.Length - offset, PageSize);
 
-                    data.Slice(offset, size).CopyTo(_backingMemory.GetSpan(pa, size));
+                        data.Slice(offset, size).CopyTo(_backingMemory.GetSpan(pa, size));
+                    }
+                }
+            }
+            catch (InvalidMemoryRegionException)
+            {
+                if (_invalidAccessHandler == null || !_invalidAccessHandler(va))
+                {
+                    throw;
                 }
             }
         }
@@ -172,6 +197,7 @@ namespace Ryujinx.Cpu
         /// <param name="va">Virtual address of the data</param>
         /// <param name="size">Size of the data</param>
         /// <returns>A read-only span of the data</returns>
+        /// <exception cref="InvalidMemoryRegionException">Throw for unhandled invalid or unmapped memory accesses</exception>
         public ReadOnlySpan<byte> GetSpan(ulong va, int size)
         {
             if (size == 0)
@@ -179,7 +205,7 @@ namespace Ryujinx.Cpu
                 return ReadOnlySpan<byte>.Empty;
             }
 
-            if (IsContiguous(va, size))
+            if (IsContiguousAndMapped(va, size))
             {
                 return _backingMemory.GetSpan(GetPhysicalAddressInternal(va), size);
             }
@@ -204,6 +230,7 @@ namespace Ryujinx.Cpu
         /// <param name="va">Virtual address of the data</param>
         /// <param name="size">Size of the data</param>
         /// <returns>A writable region of memory containing the data</returns>
+        /// <exception cref="InvalidMemoryRegionException">Throw for unhandled invalid or unmapped memory accesses</exception>
         public WritableRegion GetWritableRegion(ulong va, int size)
         {
             if (size == 0)
@@ -211,7 +238,7 @@ namespace Ryujinx.Cpu
                 return new WritableRegion(null, va, Memory<byte>.Empty);
             }
 
-            if (IsContiguous(va, size))
+            if (IsContiguousAndMapped(va, size))
             {
                 return new WritableRegion(null, va, _backingMemory.GetMemory(GetPhysicalAddressInternal(va), size));
             }
@@ -234,6 +261,7 @@ namespace Ryujinx.Cpu
         /// <typeparam name="T">Type of the data to get the reference</typeparam>
         /// <param name="va">Virtual address of the data</param>
         /// <returns>A reference to the data in memory</returns>
+        /// <exception cref="MemoryNotContiguousException">Throw if the specified memory region is not contiguous in physical memory</exception>
         public ref T GetRef<T>(ulong va) where T : unmanaged
         {
             if (!IsContiguous(va, Unsafe.SizeOf<T>()))
@@ -257,6 +285,9 @@ namespace Ryujinx.Cpu
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        private bool IsContiguousAndMapped(ulong va, int size) => IsContiguous(va, size) && IsMapped(va);
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         private bool IsContiguous(ulong va, int size)
         {
             if (!ValidateAddress(va))
@@ -295,26 +326,36 @@ namespace Ryujinx.Cpu
                 return;
             }
 
-            int offset = 0, size;
-
-            if ((va & PageMask) != 0)
+            try
             {
-                ulong pa = GetPhysicalAddressInternal(va);
+                int offset = 0, size;
 
-                size = Math.Min(data.Length, PageSize - (int)(va & PageMask));
+                if ((va & PageMask) != 0)
+                {
+                    ulong pa = GetPhysicalAddressInternal(va);
 
-                _backingMemory.GetSpan(pa, size).CopyTo(data.Slice(0, size));
+                    size = Math.Min(data.Length, PageSize - (int)(va & PageMask));
 
-                offset += size;
-            }
+                    _backingMemory.GetSpan(pa, size).CopyTo(data.Slice(0, size));
 
-            for (; offset < data.Length; offset += size)
-            {
-                ulong pa = GetPhysicalAddressInternal(va + (ulong)offset);
+                    offset += size;
+                }
 
-                size = Math.Min(data.Length - offset, PageSize);
+                for (; offset < data.Length; offset += size)
+                {
+                    ulong pa = GetPhysicalAddressInternal(va + (ulong)offset);
+
+                    size = Math.Min(data.Length - offset, PageSize);
 
-                _backingMemory.GetSpan(pa, size).CopyTo(data.Slice(offset, size));
+                    _backingMemory.GetSpan(pa, size).CopyTo(data.Slice(offset, size));
+                }
+            }
+            catch (InvalidMemoryRegionException)
+            {
+                if (_invalidAccessHandler == null || !_invalidAccessHandler(va))
+                {
+                    throw;
+                }
             }
         }
 
@@ -416,6 +457,7 @@ namespace Ryujinx.Cpu
         /// </summary>
         /// <param name="va">Virtual address to check</param>
         /// <returns>True if the address is mapped, false otherwise</returns>
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
         public bool IsMapped(ulong va)
         {
             if (!ValidateAddress(va))
author	gdkchan <gab.dark.100@gmail.com>	2020-07-30 10:16:41 -0300
committer	GitHub <noreply@github.com>	2020-07-30 23:16:41 +1000
commit	57bb0abda3dc277dc7575250fdb080edb83abcbc (patch)
tree	21fd7e3cdea856037c4794e2de0b68ff80be4b63 /Ryujinx.Cpu
parent	636542d817b3403ae44b46a48a67cedc0c7b42c5 (diff)