diff --git a/Makefile b/Makefile
index 4546afb2d8d2a11810a595fd97bece1b75e27f58..97d54e3d3654856aa022bc82d6962b83db4ba391 100644
--- a/Makefile
+++ b/Makefile
@@ -38,7 +38,7 @@ endif
 
 .DEFAULT_GOAL := help
 
-.PHONY: $(SUPPORTED_SUITES) run inject help build longevity-prereqs longevity-prereqs-all longevity-matrix
+.PHONY: $(SUPPORTED_SUITES) run inject help build longevity-prereqs longevity-prereqs-all longevity-matrix build-stress-ng build-stress-ng-all
 
 $(SUPPORTED_SUITES):
 	@STARRY_MODE=$(STARRY_MODE) $(RUNNER) $(SUITE) $(STARRY_MODE)
@@ -52,6 +52,12 @@ longevity-prereqs-all:
 longevity-matrix:
 	@"$(CURDIR)/scripts/run-longevity-matrix.sh"
 
+build-stress-ng:
+	@"$(CURDIR)/scripts/build-stress-ng.sh" "$(ARCH)"
+
+build-stress-ng-all:
+	@"$(CURDIR)/scripts/build-stress-ng.sh" all
+
 run inject:
 	@# helper target so `make ci-test inject` works as expected
 
@@ -69,6 +75,8 @@ help:
 	@echo "  make longevity-prereqs      # check guest binaries for one ARCH + CASES"
 	@echo "  make longevity-prereqs-all  # prereqs × aarch64/riscv64/x86_64 (CASES=stress-ng-soak default)"
 	@echo "  make longevity-matrix       # sequential matrix; CASES= for fs/net soak cases"
+	@echo "  make build-stress-ng        # musl static stress-ng + pthread (ARCH=)"
+	@echo "  CASES=stress-ng-concurrency-soak make longevity-test run"
 	@echo "  make build                  # compile the Rust harness"
 	@echo ""
 	@echo "Yocto ptest targets:"
diff --git a/scripts/build-stress-ng.sh b/scripts/build-stress-ng.sh
new file mode 100755
index 0000000000000000000000000000000000000000..f313e9a297771b2442b106787b4ea0b81845f9a7
--- /dev/null
+++ b/scripts/build-stress-ng.sh
@@ -0,0 +1,88 @@
+#!/usr/bin/env bash
+# Cross-build static musl stress-ng with pthread for longevity concurrency soak.
+# Usage: ./scripts/build-stress-ng.sh [aarch64|riscv64|x86_64|all]
+#
+# Note: musl cross builds often omit stress-ng --mutex (needs setprioceiling);
+# concurrency soak uses --mtx (C11 threads) instead — see run-concurrency-soak.sh.
+set -euo pipefail
+REPO_ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+STRESSNG_SRC="${STRESSNG_SRC:-${REPO_ROOT}/.cache/stress-ng}"
+
+build_one() {
+  local arch="$1"
+  local cc
+  # musl-gcc defaults to PIE: -static alone yields "dynamically linked" ET_DYN; need -no-pie.
+  local ldflags="-static -no-pie -pthread"
+  case "$arch" in
+    aarch64) cc=aarch64-linux-musl-gcc ;;
+    riscv64) cc=riscv64-linux-musl-gcc; ldflags="-static -no-pie -pthread -latomic" ;;
+    x86_64)  cc=x86_64-linux-musl-gcc ;;
+    *)
+      printf 'Unsupported arch: %s\n' "$arch" >&2
+      return 1
+      ;;
+  esac
+  if ! command -v "$cc" >/dev/null 2>&1; then
+    printf 'Need cross compiler: %s\n' "$cc" >&2
+    return 1
+  fi
+
+  if [[ ! -d "$STRESSNG_SRC" ]]; then
+    git clone --depth 1 https://github.com/ColinIanKing/stress-ng.git "$STRESSNG_SRC"
+  fi
+
+  local cxx="${cc%-gcc}-g++"
+  printf '=== building stress-ng for %s (%s, STATIC + pthread) ===\n' "$arch" "$cc"
+  (
+    cd "$STRESSNG_SRC"
+    make clean cleanconfig >/dev/null 2>&1 || true
+    make -j"$(nproc)" \
+      CC="$cc" CXX="$cxx" \
+      STATIC=1 \
+      LDFLAGS="$ldflags"
+  )
+
+  local dest="${REPO_ROOT}/tests/stress-ng/${arch}"
+  mkdir -p "$dest"
+  install -m 0755 "${STRESSNG_SRC}/stress-ng" "${dest}/stress-ng"
+
+  local ftype
+  ftype="$(file -b "${dest}/stress-ng")"
+  if printf '%s' "$ftype" | grep -q 'statically linked'; then
+    printf 'OK: %s (%s)\n' "${dest}/stress-ng" "$ftype"
+  else
+    printf 'ERROR: %s is not statically linked: %s\n' "${dest}/stress-ng" "$ftype" >&2
+    printf '  guest inject needs musl static executable; use STATIC=1 LDFLAGS="%s"\n' "$ldflags" >&2
+    return 1
+  fi
+
+  "${dest}/stress-ng" --version 2>&1 | head -1 || true
+  ARCH="$arch" "${REPO_ROOT}/scripts/check-stress-ng-concurrency.sh"
+  printf '\n>>> build-stress-ng %s: SUCCESS <<<\n\n' "$arch"
+}
+
+target="${1:-aarch64}"
+failures=0
+built_ok=()
+if [[ "$target" == "all" ]]; then
+  for a in aarch64 riscv64 x86_64; do
+    if build_one "$a"; then
+      built_ok+=("$a")
+    else
+      printf 'FAIL: build-stress-ng %s\n' "$a" >&2
+      failures=$((failures + 1))
+    fi
+  done
+  printf '=== build-stress-ng-all summary ===\n'
+  if [[ ${#built_ok[@]} -gt 0 ]]; then
+    printf '  OK  : %s\n' "${built_ok[*]}"
+  fi
+  if [[ "$failures" -ne 0 ]]; then
+    printf '  FAIL: %s architecture(s)\n' "$failures" >&2
+    exit 1
+  fi
+  printf 'All architectures built (static + mtx prereq). Next:\n'
+  printf '  CASES=stress-ng-concurrency-soak make longevity-matrix\n'
+else
+  build_one "$target"
+fi
diff --git a/scripts/check-longevity-prereqs.sh b/scripts/check-longevity-prereqs.sh
index c580f7ef539e7398a200b8e83b142ff427f5a9c2..8878b29104d49389c11d675a661109b7ace8b28d 100755
--- a/scripts/check-longevity-prereqs.sh
+++ b/scripts/check-longevity-prereqs.sh
@@ -40,6 +40,9 @@ cases_norm="$(printf '%s' "$CASES" | tr ', ' '  ')"
 if cases_need_tool "$cases_norm" "stress-ng-soak"; then
   need_stress=1
 fi
+if cases_need_tool "$cases_norm" "stress-ng-concurrency-soak"; then
+  need_stress=1
+fi
 if cases_need_tool "$cases_norm" "fio-soak-ext4"; then
   need_fio=1
 fi
@@ -66,6 +69,13 @@ if [[ "$need_stress" -eq 1 ]]; then
   check_file "$REPO_ROOT/tests/stress-ng/$ARCH/stress-ng" \
     "musl static build — see tests/stress-ng/BUILD.md"
 fi
+if cases_need_tool "$cases_norm" "stress-ng-concurrency-soak"; then
+  if [[ -x "$REPO_ROOT/tests/stress-ng/$ARCH/stress-ng" ]]; then
+    if ! ARCH="$ARCH" "${REPO_ROOT}/scripts/check-stress-ng-concurrency.sh"; then
+      missing=1
+    fi
+  fi
+fi
 if [[ "$need_fio" -eq 1 ]]; then
   check_file "$REPO_ROOT/tests/fio/$ARCH/fio" \
     "see tests/fio/BUILD.md"
diff --git a/scripts/check-stress-ng-concurrency.sh b/scripts/check-stress-ng-concurrency.sh
new file mode 100755
index 0000000000000000000000000000000000000000..b9e723e497ce574cd062a206ea958d8e39905e72
--- /dev/null
+++ b/scripts/check-stress-ng-concurrency.sh
@@ -0,0 +1,39 @@
+#!/usr/bin/env bash
+# Host-side: verify stress-ng binary supports concurrency stressors (not all skipped).
+# Uses mtx (C11 mutex), not --mutex (often missing on musl cross builds).
+# Usage: ARCH=aarch64 ./scripts/check-stress-ng-concurrency.sh
+set -euo pipefail
+REPO_ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+ARCH="${ARCH:-aarch64}"
+BIN="${REPO_ROOT}/tests/stress-ng/${ARCH}/stress-ng"
+# fork / mtx / sem / futex — lock pressure via mtx instead of pthread mutex
+REQUIRED_STRESSORS="fork mtx sem futex"
+
+if [[ ! -x "$BIN" ]]; then
+  printf 'Missing: %s (see scripts/build-stress-ng.sh)\n' "$BIN" >&2
+  exit 1
+fi
+
+stressor_skipped() {
+  local s="$1"
+  local out
+  out="$("$BIN" --dry-run "--$s" 1 2>&1)" || true
+  printf '%s\n' "$out" | grep -qE "skipped:.*${s}|${s} stressor will be skipped"
+}
+
+missing=0
+for s in $REQUIRED_STRESSORS; do
+  if stressor_skipped "$s"; then
+    printf 'SKIP: stressor %s not available in %s\n' "$s" "$BIN" >&2
+    "$BIN" --dry-run "--$s" 1 2>&1 | grep -E 'skipped:|will be skipped' | head -3 >&2 || true
+    missing=1
+  fi
+done
+
+if [[ "$missing" -ne 0 ]]; then
+  printf '\nRebuild: ./scripts/build-stress-ng.sh %s\n' "$ARCH" >&2
+  printf 'Note: --mutex often fails on musl cross; soak uses --mtx.\n' >&2
+  exit 1
+fi
+
+printf 'OK: stress-ng concurrency stressors available (ARCH=%s: %s)\n' "$ARCH" "$REQUIRED_STRESSORS"
diff --git a/scripts/longevity-common.sh b/scripts/longevity-common.sh
index 5f765f08f69e3f198b054cdb54a787165e9d3a82..56733488e231f8c3eb3ceee427bf96a3bc92ed74 100755
--- a/scripts/longevity-common.sh
+++ b/scripts/longevity-common.sh
@@ -13,4 +13,4 @@ LONGEVITY_MATRIX_ARCHES="${LONGEVITY_MATRIX_ARCHES:-aarch64 riscv64 x86_64}"
 # ping-flood-soak uses BusyBox ping — no extra binary.
 
 # Full longevity case names (for docs / CASES= help).
-LONGEVITY_ALL_CASES="stress-ng-soak fio-soak-ext4 fs-soak-ext4 iperf3-soak-guest-client ping-flood-soak net-soak-guest-client"
+LONGEVITY_ALL_CASES="stress-ng-soak stress-ng-concurrency-soak fio-soak-ext4 fs-soak-ext4 iperf3-soak-guest-client ping-flood-soak net-soak-guest-client"
diff --git a/tests/longevity/README.md b/tests/longevity/README.md
new file mode 100644
index 0000000000000000000000000000000000000000..8d16f818e5b95b7ef2f520714e03710115882f60
--- /dev/null
+++ b/tests/longevity/README.md
@@ -0,0 +1,55 @@
+# Longevity / soak 套件
+
+入口：`make longevity-test run`（默认 `ARCH=aarch64`）。
+
+## Case 列表
+
+| Case | 工具 | 说明 |
+|------|------|------|
+| `stress-ng-soak` | stress-ng | cpu/vm/io 综合压力 |
+| **`stress-ng-concurrency-soak`** | stress-ng | **fork + mtx + sem + futex**（mtx 替代 musl 上常缺的 mutex） |
+| `fio-soak-ext4` | fio | 块设备 randrw |
+| `fs-soak-ext4` | fsstress + fio | 元数据 + IO |
+| `iperf3-soak-guest-client` | iperf3 | TCP/UDP 长连接 |
+| `ping-flood-soak` | ping | flood 打网关 |
+| `net-soak-guest-client` | iperf3 + ping | 网络组合 |
+
+脚本在 `tests/{stress-ng,fio,fsstress,iperf3}/`；本目录仅 `suite.toml` + `soak-common.sh`。
+
+## 并发 soak（stress-ng-concurrency-soak）
+
+```bash
+# 1. 静态 musl + pthread 重编 stress-ng（soak 用 --mtx，不用常缺的 --mutex）
+make build-stress-ng ARCH=aarch64
+
+# 2. 预检
+CASES=stress-ng-concurrency-soak ARCH=aarch64 make longevity-prereqs
+
+# 3. 冒烟 ~2min
+export XKERNEL_REMOTE=/path/to/x-kernel
+CASES=stress-ng-concurrency-soak ARCH=aarch64 make longevity-test run
+
+# 4. 三架构矩阵
+CASES=stress-ng-concurrency-soak make longevity-matrix
+```
+
+调压力（`suite.toml` 的 `guest_env`）：
+
+```toml
+guest_env = "LONGEVITY_SOAK_SEC=120 STRESSNG_FORK_PROCS=4 STRESSNG_MTX_PROCS=2"
+```
+
+生产时长：guest 脚本首参或 `LONGEVITY_SOAK_SEC=7200`，`timeout_secs` ≥ soak + 900。
+
+若 guest 因内核问题（如 `pause` 未实现、OOM）在矩阵里失败，可先用冒烟降压：
+
+```toml
+guest_env = "LONGEVITY_SOAK_SEC=120 STRESSNG_FORK_PROCS=1 STRESSNG_MTX_PROCS=1 STRESSNG_SEM_PROCS=1 STRESSNG_FUTEX_PROCS=1 STRESSNG_CPU_PROCS=1"
+```
+
+## 矩阵
+
+```bash
+make longevity-prereqs-all
+CASES=stress-ng-concurrency-soak make longevity-matrix
+```
diff --git a/tests/longevity/soak-common.sh b/tests/longevity/soak-common.sh
new file mode 100755
index 0000000000000000000000000000000000000000..ed1011915eb1984830179dcc3e815df6154a32a8
--- /dev/null
+++ b/tests/longevity/soak-common.sh
@@ -0,0 +1,27 @@
+# Shared helpers for longevity guest soak scripts (source from run-*.sh).
+# Usage: . "$(dirname "$0")/soak-common.sh"   # when copied to /root/longevity/
+#        . /root/longevity/soak-common.sh      # after harness inject
+
+longevity_soak_seconds() {
+  if [ -n "${1:-}" ]; then
+    printf '%s' "$1"
+    return 0
+  fi
+  if [ -n "${LONGEVITY_SOAK_SEC:-}" ]; then
+    printf '%s' "$LONGEVITY_SOAK_SEC"
+    return 0
+  fi
+  printf '%s' "${LONGEVITY_SOAK_SEC_DEFAULT:-120}"
+}
+
+longevity_mem_snapshot() {
+  tag="${1:-mem}"
+  printf '=== mem snapshot [%s] ===\n' "$tag"
+  if [ -r /proc/meminfo ]; then
+    grep -E '^(MemTotal|MemFree|MemAvailable|Buffers|Cached|SwapTotal|SwapFree):' \
+      /proc/meminfo || true
+  fi
+  if command -v free >/dev/null 2>&1; then
+    free || true
+  fi
+}
diff --git a/tests/longevity/suite.toml b/tests/longevity/suite.toml
index 56f8b27a7ba65061ff9711190af21b3ffd322455..5450393039ca01840097c16dd66a74ebbd729c38 100644
--- a/tests/longevity/suite.toml
+++ b/tests/longevity/suite.toml
@@ -6,11 +6,11 @@
 # Default smoke: guest script first arg 120s. Production: 7200/43200;
 # timeout_secs ≥ soak_seconds + 900; iperf3 cases need companion_timeout_secs ≥ TCP + UDP + margin.
 #
-# Cases: stress-ng-soak | fio-soak-ext4 | fs-soak-ext4 | iperf3-soak-guest-client |
-#        ping-flood-soak | net-soak-guest-client
+# Cases: stress-ng-soak | stress-ng-concurrency-soak | fio-soak-ext4 | fs-soak-ext4 |
+#        iperf3-soak-guest-client | ping-flood-soak | net-soak-guest-client
 # Scripts: tests/{stress-ng,fio,fsstress,iperf3}/run-*.sh
 name = "longevity-test"
-description = "长稳：stress-ng / fio / fs-soak / iperf3 / ping / net-soak（见各目录 run-*.sh）"
+description = "长稳：stress-ng（含并发）/ fio / fs-soak / iperf3 / ping / net-soak（见各目录 run-*.sh）"
 build_script = "scripts/build_xkernel.sh"
 arch = "aarch64"
 default_timeout_secs = 900
@@ -30,6 +30,26 @@ dest = "/root/longevity/stress-ng"
 src = "tests/stress-ng/run-soak.sh"
 dest = "/root/longevity/run-soak.sh"
 
+[[cases]]
+name = "stress-ng-concurrency-soak"
+description = "stress-ng 并发竞争：fork + mtx + sem + futex（静态 musl+pthread；mtx 替代 musl 上常缺的 mutex）"
+runner = "guest-test"
+guest_command = "sh -c 'chmod +x /root/longevity/stress-ng /root/longevity/run-concurrency-soak.sh /root/longevity/soak-common.sh && sh /root/longevity/run-concurrency-soak.sh 120'"
+guest_env = "LONGEVITY_SOAK_SEC=120"
+timeout_secs = 900
+
+[[cases.inject]]
+src = "tests/stress-ng/${ARCH}/stress-ng"
+dest = "/root/longevity/stress-ng"
+
+[[cases.inject]]
+src = "tests/stress-ng/run-concurrency-soak.sh"
+dest = "/root/longevity/run-concurrency-soak.sh"
+
+[[cases.inject]]
+src = "tests/longevity/soak-common.sh"
+dest = "/root/longevity/soak-common.sh"
+
 [[cases]]
 name = "fio-soak-ext4"
 description = "fio randrw 持续占盘；首参为秒数"
diff --git a/tests/stress-ng/BUILD.md b/tests/stress-ng/BUILD.md
index 46b49fd54f7cd4c259d69b0f41ea26df17002c48..ce2255bb6481c910c71371db45b74a5c5bedf51a 100644
--- a/tests/stress-ng/BUILD.md
+++ b/tests/stress-ng/BUILD.md
@@ -10,10 +10,20 @@ stress-ng/
 └── loongarch64/stress-ng
 ```
 
+## 一键编译（含 pthread，供 concurrency soak）
+
+```bash
+./scripts/build-stress-ng.sh aarch64   # 或 riscv64 / x86_64 / all
+make build-stress-ng ARCH=aarch64
+```
+
+脚本会执行 `check-stress-ng-concurrency.sh`，确认 **fork/mtx/sem/futex** 未被 skip（不用 `--mutex`，musl 交叉编时常未实现）。
+
 ## 推荐编译参数
 
 - 必须同时为 **`CC` / `CXX`** 指定**同一 triple** 的 `*-linux-musl-gcc` / `*-linux-musl-g++`，否则生成 C++ 目标（如 `stress-eigen-ops`、`stress-vecmath`、`core-perf`）时会落到宿主机 `g++`，易出现链接或运行环境不一致。
 - 设 **`STATIC=1`**，与 guest 无动态链接器的场景一致。
+- **并发 soak** 需 **pthread**，且 musl 须 **` -static -no-pie`**（仅 `-static` 会得到 PIE 的 `dynamically linked`，guest 注入不适用）。`build-stress-ng.sh` 已包含；`--mutex` 常缺，soak 用 **`--mtx`**。
 - **riscv64** 与 **loongarch64** 静态链接时若报 `undefined reference to __atomic_*`，在链接阶段加上 **`LDFLAGS=-latomic`**。
 - 共用同一源码目录交叉多架构时，每个架构前执行 **`make clean`**，避免残留目标文件。
 
diff --git a/tests/stress-ng/README.md b/tests/stress-ng/README.md
index 4d6b2ff3cdec271f270541c425d4c746929eed02..503de0f220a79d34bf4f5a832950625d360864ac 100644
--- a/tests/stress-ng/README.md
+++ b/tests/stress-ng/README.md
@@ -1,6 +1,13 @@
 # stress-ng（guest 预编译）
 
-Longevity **已验证链路**的 guest 工具：注入 `tests/stress-ng/<arch>/stress-ng` 与 `run-soak.sh`，在 guest 内跑 `stress-ng-soak`（cpu/vm/io 并行）。
+Longevity guest 工具：注入 `tests/stress-ng/<arch>/stress-ng` 与 soak 脚本。
+
+| Case | 脚本 |
+|------|------|
+| `stress-ng-soak` | `run-soak.sh`（cpu/vm/io） |
+| `stress-ng-concurrency-soak` | `run-concurrency-soak.sh`（fork/**mtx**/sem/futex） |
+
+**并发 case** 用 `scripts/build-stress-ng.sh`（`-static -pthread`）。musl 交叉编译里 `--mutex` 常因缺少 `setprioceiling` 未编入，故用 **`--mtx`**（C11 线程互斥）。
 
 编译见 [BUILD.md](BUILD.md)。
 
@@ -9,6 +16,7 @@ Longevity **已验证链路**的 guest 工具：注入 `tests/stress-ng/<arch>/s
 ```bash
 export XKERNEL_REMOTE=/path/to/x-kernel/x-kernel
 make longevity-prereqs-all
+CASES=stress-ng-concurrency-soak ARCH=aarch64 make longevity-test run
 make longevity-matrix              # 默认 CASES=stress-ng-soak × aarch64/riscv64/x86_64
 CASES=fs-soak-ext4 make longevity-matrix   # 另需 tests/fsstress/<arch>/fsstress（三架构）
 ARCH=aarch64 make longevity-test run
diff --git a/tests/stress-ng/aarch64/stress-ng b/tests/stress-ng/aarch64/stress-ng
index 07756376c08fba2646e3f037a1a2a02e14ad440f..12e4abb82613fd3d93d26a646db2e3cbc10fad3d 100755
Binary files a/tests/stress-ng/aarch64/stress-ng and b/tests/stress-ng/aarch64/stress-ng differ
diff --git a/tests/stress-ng/riscv64/stress-ng b/tests/stress-ng/riscv64/stress-ng
index 4089f0092fbb769ab76fd1613ab8ad90c5fe1d22..dfcb3609f383e4f2e43fd10db42b9fcde508000d 100755
Binary files a/tests/stress-ng/riscv64/stress-ng and b/tests/stress-ng/riscv64/stress-ng differ
diff --git a/tests/stress-ng/run-concurrency-soak.sh b/tests/stress-ng/run-concurrency-soak.sh
new file mode 100755
index 0000000000000000000000000000000000000000..25340c7e1494cc66c3e27786c62f8f471df12927
--- /dev/null
+++ b/tests/stress-ng/run-concurrency-soak.sh
@@ -0,0 +1,80 @@
+#!/bin/sh
+# Guest: stress-ng concurrency soak — fork + mtx + sem + futex (+ light cpu).
+# Uses --mtx (C11 threads mutex), not --mutex (often unimplemented in musl static builds).
+# First argument or LONGEVITY_SOAK_SEC = duration in seconds (default 120 smoke).
+set -eu
+
+BASEDIR="$(cd "$(dirname "$0")" && pwd)"
+STRESS="${BASEDIR}/stress-ng"
+COMMON="${BASEDIR}/soak-common.sh"
+if [ -f "$COMMON" ]; then
+  # shellcheck source=/dev/null
+  . "$COMMON"
+else
+  longevity_soak_seconds() {
+    if [ -n "${1:-}" ]; then printf '%s' "$1"; return; fi
+    if [ -n "${LONGEVITY_SOAK_SEC:-}" ]; then printf '%s' "$LONGEVITY_SOAK_SEC"; return; fi
+    printf '%s' 120
+  }
+  longevity_mem_snapshot() { :; }
+fi
+
+SOAK_SEC="$(longevity_soak_seconds "${1:-}")"
+
+FORK_PROCS="${STRESSNG_FORK_PROCS:-2}"
+MTX_PROCS="${STRESSNG_MTX_PROCS:-${STRESSNG_MUTEX_PROCS:-2}}"
+SEM_PROCS="${STRESSNG_SEM_PROCS:-2}"
+FUTEX_PROCS="${STRESSNG_FUTEX_PROCS:-2}"
+CPU_PROCS="${STRESSNG_CPU_PROCS:-1}"
+
+if [ ! -x "$STRESS" ]; then
+  printf 'ERROR: stress-ng not executable: %s\n' "$STRESS" >&2
+  exit 1
+fi
+
+stressor_skipped() {
+  name="$1"
+  out="$("$STRESS" --dry-run "--$name" 1 2>&1)" || true
+  printf '%s\n' "$out" | grep -q "skipped:.*${name}\|${name} stressor will be skipped"
+}
+
+check_stressor() {
+  name="$1"
+  if stressor_skipped "$name"; then
+    printf 'FAIL: stress-ng stressor "%s" skipped on this guest\n' "$name" >&2
+    printf '  → host: ./scripts/build-stress-ng.sh (STATIC + pthread)\n' >&2
+    printf '  → guest: X-Kernel may lack threads/mutex/futex APIs stress-ng needs\n' >&2
+    "$STRESS" --dry-run "--$name" 1 2>&1 | grep -E 'skipped:|will be skipped' >&2 || true
+    return 1
+  fi
+  return 0
+}
+
+printf '=== longevity stress-ng concurrency soak: %s s ===\n' "$SOAK_SEC"
+printf '  procs: fork=%s mtx=%s sem=%s futex=%s cpu=%s\n' \
+  "$FORK_PROCS" "$MTX_PROCS" "$SEM_PROCS" "$FUTEX_PROCS" "$CPU_PROCS"
+
+longevity_mem_snapshot start
+
+rc=0
+for s in fork mtx sem futex; do
+  check_stressor "$s" || rc=1
+done
+if [ "$rc" -ne 0 ]; then
+  exit 1
+fi
+
+"$STRESS" \
+  --fork "$FORK_PROCS" \
+  --mtx "$MTX_PROCS" \
+  --sem "$SEM_PROCS" \
+  --futex "$FUTEX_PROCS" \
+  --cpu "$CPU_PROCS" \
+  --timeout "$SOAK_SEC" \
+  --metrics-brief \
+  --verbose
+stress_rc=$?
+
+longevity_mem_snapshot end
+printf '=== concurrency soak finished (exit=%s) ===\n' "$stress_rc"
+exit "$stress_rc"
diff --git a/tests/stress-ng/x86_64/stress-ng b/tests/stress-ng/x86_64/stress-ng
index afa54e80e8e0aa19fc28c18d030f68f38cc17247..90f4634bd6ee025353c9963e87e58bfcc08b476b 100755
Binary files a/tests/stress-ng/x86_64/stress-ng and b/tests/stress-ng/x86_64/stress-ng differ