Astro Bot stack: VEH/TBB, title clear, swapchain fallback, Psml MFSR (#528)

* Cpu/Kernel: harden VEH trampoline and keep TBB on native workers

Route FastFail/CLR/stack-overflow around managed VEH, serialize managed
entry with a recursive spinlock, require native workers for tbb_thead,
and abandon pthread mutexes when a guest thread is torn down by worker
abort so splash waiters are not left holding locks forever.

* Cpu: soft-fail TBB native worker storms and cap concurrent Runs

Throwing on worker/prologue faults killed the process mid tbb_thead
burst (FailFast 0xC0000409). Soft-return 0x80020012, limit in-flight
native Runs (default 2), and keep prewarm small so back-to-back boots
do not need an artificial settle delay.

* Agc/VideoOut: poison-only empty-SRT reject and clear procedural ES/PS

Skip QueueSubmit only when Address-0 image slots remain; run the
Astro title clear pair via CmdClearColorImage so the pass executes
without descriptors that lose the device.

* VideoOut: recreate swapchain with fallback extent on 0x0 surface

Minimized Win32 surfaces report 0x0 / MaxImageExtent=0; deferring
recreate forever left an OutOfDate swapchain with no presents.
Clamp to last/default size and recreate instead of early-return.

* Psml: stub MFSR init/shared/context and dispatch packet size

Astro Bot asserts in GfxRenderStagePSSR when scePsmlMfsrInit is unresolved
(Mfsr initialized failed). Soft HLE for the MFSR shared-resource and
800M3_2 context path plus dispatch packet size lets boot pass splash to
first frame without claiming real upscaling.

* Psml: stub MFSR GetDispatchMfsrPacket900 for logo PSSR

Astro StartLevel ps_logo asserted GfxRenderStagePSSR.cpp:266 when
GetDispatchMfsrPacket900 (RUNLFro+qok) was unresolved. Return SCE_OK
from SizeInDwords so the 900 fill runs, soft-clear the guest packet
buffer, and register 1000/1100 siblings for the same ABI.

src/SharpEmu.Libs/Kernel/KernelPthreadCompatExports.cs

@@ -153,6 +153,64 @@ public static class KernelPthreadCompatExports
     static KernelPthreadCompatExports()
     {
         RunSynchronizationSelfChecks();
+        GuestThreadExecution.GuestThreadAbandoned += AbandonMutexesOwnedByThread;
+    }
+
+    /// <summary>
+    /// Force-release mutexes still owned by a guest thread that is being torn
+    /// down without a clean unlock (TBB worker_abort, abrupt exit). Otherwise
+    /// waiters can spin forever and block splash→first GPU submit.
+    /// </summary>
+    public static int AbandonMutexesOwnedByThread(ulong threadId, string reason)
+    {
+        if (threadId == 0)
+        {
+            return 0;
+        }
+
+        var released = 0;
+        var wakeKeys = new List<string>();
+        foreach (var pair in _mutexStates)
+        {
+            var state = pair.Value;
+            string? wakeKey = null;
+            lock (state)
+            {
+                if (state.OwnerThreadId != threadId || state.RecursionCount <= 0)
+                {
+                    continue;
+                }
+
+                state.OwnerThreadId = 0;
+                state.RecursionCount = 0;
+                wakeKey = state.Waiters.First?.Value.Cooperative == true
+                    ? state.Waiters.First.Value.WakeKey
+                    : null;
+                Monitor.PulseAll(state);
+                released++;
+                Console.Error.WriteLine(
+                    $"[LOADER][WARN] pthread_mutex_abandon mutex=0x{pair.Key:X16} " +
+                    $"owner={KernelPthreadState.DescribeThreadHandle(threadId)} " +
+                    $"reason={reason} waiters={state.Waiters.Count}");
+            }
+
+            if (wakeKey is not null)
+            {
+                wakeKeys.Add(wakeKey);
+            }
+        }
+
+        foreach (var wakeKey in wakeKeys)
+        {
+            _ = GuestThreadExecution.Scheduler?.WakeBlockedThreads(wakeKey, 1);
+        }
+
+        if (released > 0)
+        {
+            Console.Error.Flush();
+        }
+
+        return released;
     }
 
     [SysAbiExport(

src/SharpEmu.Libs/Kernel/KernelPthreadState.cs

@@ -27,8 +27,12 @@ internal static class KernelPthreadState
     internal static ulong GetCurrentThreadHandle()
     {
         var guestThreadHandle = GuestThreadExecution.CurrentGuestThreadHandle;
-        if (guestThreadHandle != 0 && TryGetThreadIdentity(guestThreadHandle, out _))
+        // Prefer the bound guest handle even when it is not yet in Threads.
+        // Falling through to a synthetic ThreadStatic handle while a guest
+        // thread is bound causes mutex owner mismatches (unlock PERM → hang).
+        if (guestThreadHandle != 0)
         {
+            EnsureGuestThreadIdentity(guestThreadHandle);
             return guestThreadHandle;
         }
 
@@ -39,15 +43,27 @@ internal static class KernelPthreadState
     internal static ulong GetCurrentThreadUniqueId()
     {
         var guestThreadHandle = GuestThreadExecution.CurrentGuestThreadHandle;
-        if (guestThreadHandle != 0 && TryGetThreadIdentity(guestThreadHandle, out var identity))
+        if (guestThreadHandle != 0)
         {
-            return identity.UniqueId;
+            return EnsureGuestThreadIdentity(guestThreadHandle).UniqueId;
         }
 
         EnsureCurrentThreadRegistered();
         return _currentThreadUniqueId;
     }
 
+    internal static string DescribeThreadHandle(ulong threadHandle)
+    {
+        if (threadHandle == 0)
+        {
+            return "none";
+        }
+
+        return TryGetThreadIdentity(threadHandle, out var identity)
+            ? $"0x{threadHandle:X16}('{identity.Name}')"
+            : $"0x{threadHandle:X16}";
+    }
+
     internal static ulong CreateThreadHandle(string name)
     {
         var uniqueId = unchecked((ulong)Interlocked.Increment(ref _nextUniqueThreadId));
@@ -59,6 +75,18 @@ internal static class KernelPthreadState
         return Threads.TryGetValue(threadHandle, out identity);
     }
 
+    private static ThreadIdentity EnsureGuestThreadIdentity(ulong guestThreadHandle)
+    {
+        if (Threads.TryGetValue(guestThreadHandle, out var existing))
+        {
+            return existing;
+        }
+
+        var uniqueId = unchecked((ulong)Interlocked.Increment(ref _nextUniqueThreadId));
+        var identity = new ThreadIdentity(uniqueId, $"Guest-0x{guestThreadHandle:X}");
+        return Threads.GetOrAdd(guestThreadHandle, identity);
+    }
+
     private static void EnsureCurrentThreadRegistered()
     {
         if (_currentThreadHandle != 0)