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, 43 insertions, 0 deletions

diff --git a/userspace/cuda/570.144/scripts/ghidra_decompile.sh b/userspace/cuda/570.144/scripts/ghidra_decompile.sh
new file mode 100755
index 0000000..bf95e8c
--- /dev/null
+++ b/userspace/cuda/570.144/scripts/ghidra_decompile.sh
@@ -0,0 +1,43 @@
+#!/bin/bash
+# SPDX-License-Identifier: BSD-3-Clause
+#
+# ghidra_decompile.sh - decompile the function containing a file vaddr.
+#
+# Runs Ghidra headless with -noanalysis: the program is imported, the crash
+# address is disassembled and turned into a function on demand, then
+# decompiled. That avoids a full auto-analysis pass over a ~70 MB library.
+#
+# Usage: scripts/ghidra_decompile.sh <binary> <hex-vaddr> [outfile]
+#   env: GHIDRA_HOME (default: /snap/ghidra/current/ghidra)
+#        PROJECT_DIR (default: ../run/ghidra-proj)
+#
+# Output: run/<basename>_<vaddr>.c unless outfile is given.
+set -e
+
+HERE="$(cd "$(dirname "$0")" && pwd)"
+ROOT="$(cd "$HERE/.." && pwd)"
+RUN="$ROOT/run"
+BIN="${1:?usage: $0 <binary> <hex-vaddr> [outfile]}"
+VADDR="${2:?usage: $0 <binary> <hex-vaddr> [outfile]}"
+OUT="${3:-$RUN/$(basename "$BIN")_${VADDR}.c}"
+
+GHIDRA_HOME="${GHIDRA_HOME:-/snap/ghidra/current/ghidra}"
+ANALYZE="$GHIDRA_HOME/support/analyzeHeadless"
+PROJECT_DIR="${PROJECT_DIR:-$RUN/ghidra-proj}"
+PROJECT_NAME="${PROJECT_NAME:-cuda-analysis}"
+
+[ -x "$ANALYZE" ] || { echo "analyzeHeadless not found at $ANALYZE"; exit 1; }
+mkdir -p "$PROJECT_DIR" "$RUN"
+
+echo "[*] decompiling $BIN at $VADDR -> $OUT"
+"$ANALYZE" "$PROJECT_DIR" "$PROJECT_NAME" \
+    -import "$BIN" \
+    -overwrite \
+    -noanalysis \
+    -scriptPath "$ROOT/ghidra" \
+    -postScript DecompileAt.java "$VADDR" "$OUT" \
+    -deleteProject \
+    2>&1 | tail -5
+
+[ -f "$OUT" ] || { echo "[FAIL] no output produced"; exit 1; }
+echo "[ok] $OUT"