userspace/cuda: libcuda analysis tree (debug-focused), guest ioctl tracer

Analysis tooling for debugging CUDA execution in Open-IOV guests:
- userspace/cuda/570.144/: fetch a library from a running guest (nc),
  objdump helpers, crash ip -> file vaddr + symbol mapping, and Ghidra
  headless import/analysis/decompile scripts (project kept so single
  functions decompile in seconds). The purpose is debugging correctness
  and performance of CUDA in Open-IOV VMs (not a reimplementation);
  extracted binaries and decompiled output are gitignored.
- tools/guest-diag/ioctl_trace.c: ptrace tracker for the NVIDIA driver
  ioctls of a child (libcuda issues raw syscalls, so LD_PRELOAD sees
  nothing). Decodes RM_ALLOC (class) and RM_CONTROL (cmd) arguments;
  this is how the cuCtxCreate crash sequence was captured.
- tools/test/cuda_drv_test.c: unbuffered + per-call markers so a crash
  identifies the CUDA call it happened in.

1 files changed, 61 insertions, 0 deletions

diff --git a/userspace/cuda/570.144/ghidra/DecompileAt.java b/userspace/cuda/570.144/ghidra/DecompileAt.java
new file mode 100644
index 0000000..5092ee9
--- /dev/null
+++ b/userspace/cuda/570.144/ghidra/DecompileAt.java
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: BSD-3-Clause
+//
+// DecompileAt.java - Ghidra post-script: decompile the function containing a
+// given address (no auto-analysis required).
+//
+// Usage (via scripts/ghidra_decompile.sh):
+//   analyzeHeadless <proj> <name> -import <binary> -noanalysis \
+//     -postScript DecompileAt.java <hex-vaddr> [outfile]
+
+import ghidra.app.script.GhidraScript;
+import ghidra.app.decompiler.DecompInterface;
+import ghidra.app.decompiler.DecompileResults;
+import ghidra.program.model.address.Address;
+import ghidra.program.model.listing.Function;
+import java.io.FileWriter;
+
+public class DecompileAt extends GhidraScript {
+    @Override
+    public void run() throws Exception {
+        String[] args = getScriptArgs();
+        if (args.length < 1) {
+            println("usage: DecompileAt.java <hex-vaddr> [outfile]");
+            return;
+        }
+        long target = Long.parseUnsignedLong(args[0].replaceFirst("^0x", ""), 16);
+        Address addr = toAddr(target);
+
+        Function f = getFunctionContaining(addr);
+        if (f == null) {
+            disassemble(addr);
+            f = createFunction(addr, null);
+        }
+        if (f == null) {
+            println("// no function at 0x" + Long.toHexString(target));
+            return;
+        }
+
+        DecompInterface dif = new DecompInterface();
+        dif.toggleCCode(true);
+        dif.toggleSyntaxTree(true);
+        dif.openProgram(currentProgram);
+
+        DecompileResults res = dif.decompileFunction(f, 120, monitor);
+        StringBuilder sb = new StringBuilder();
+        sb.append("// function ").append(f.getName())
+          .append(" at 0x").append(Long.toHexString(f.getEntryPoint().getOffset()))
+          .append(" containing 0x").append(Long.toHexString(target)).append("\n");
+        if (res != null && res.decompileCompleted()) {
+            sb.append(res.getDecompiledFunction().getC());
+        } else {
+            sb.append("// decompilation failed\n");
+        }
+        String text = sb.toString();
+        if (args.length > 1) {
+            try (FileWriter w = new FileWriter(args[1])) {
+                w.write(text);
+            }
+        }
+        println(text);
+    }
+}