feat(M13): enable FF_LOOPBACK_SUPPORT (Phase-2 P2c smoke) + sync M11-M13 docs

Phase-2 final feature milestone (P2 priority — smoke only): enable
FF_LOOPBACK_SUPPORT=1 standalone (FLOW_ISOLATE / FDIR / FLOW_IPIP /
PA / ZC reverted to isolate this test).

Code changes:

- lib/Makefile: enable FF_LOOPBACK_SUPPORT=1.

- lib/ff_stub_14_extra.c: add link-only stub for ff_swi_net_excute.
  Declared in lib/ff_host_interface.h:92 and called from
  lib/ff_dpdk_if.c:2445 inside the loopback poll loop, but the
  function never had an implementation in the F-Stack tree (M0-M12
  build had FF_LOOPBACK_SUPPORT off so the symbol was a dead
  reference). The intended behaviour is a software-interrupt-style
  network packet executor; in user-space F-Stack the equivalent
  work is done inline by ff_dpdk_if main loop, so a no-op stub is
  a safe fallback for smoke testing. Full loopback semantics may
  need revisit if a runtime path actually relies on this.

- docs/01-LAYER1-ARCHITECTURE.md + zh_cn mirror: M11/M12/M13
  combined anchor sentence (single line covering all three P2
  smoke milestones).

- docs/F-Stack_Knowledge_Base_Summary.md + zh_cn: scope tag
  amended to include M11/M12/M13.

Verification (G1-G2, single-pass / 0 bounces beyond the stub add):

- G1 lib make all: exit=0, 0 errors, 57 warnings.
- G1 example/ make: exit=0 (after stub added).
- G2 helloworld primary: ALIVE 12s+; ipfw2 + dpdk_if registered;
  no rte_exit / no SIGSEGV.
- G6 lint: 0 errors.

Bounce ledger (M13): the missing ff_swi_net_excute was a
pre-existing latent issue, not a M13 regression — it surfaced
because no prior milestone had ever enabled FF_LOOPBACK_SUPPORT.
Resolved within the same diff.

Compliance: 0 direct rm/kill/chmod calls.
Local commit only; not pushed.

Author: jfb8856606

docs/01-LAYER1-ARCHITECTURE.md

@@ -144,6 +144,7 @@ F-Stack adopted a **complete porting** strategy:
 - **Phase-2 M8 (2026-06-08)**: enabled `FF_ZC_SEND=1` (P1b, 1 bounce); introduced `FSTACK_ZC_MAGIC` sentinel (uio.uio_offset = 0xF8AC2C00F8AC2C00) protocol + new public API `ff_zc_send` to disambiguate ZC mbuf chains from plain char buffers; fixed pre-existing 13.0-baseline ZC fast-path bug where `m_uiotombuf` predicate mis-matched every `ff_write`/`ff_writev` call (would silently corrupt or GPF in `m_demote` on heavy load). 8 files +85/-4 across `freebsd/sys/mbuf.h`, `freebsd/kern/uipc_mbuf.c`, `freebsd/kern/sys_generic.c`, `lib/Makefile`, `lib/ff_syscall_wrapper.c`, `lib/ff_api.h`, `lib/ff_api.symlist`, `example/Makefile` + `example/main_zc.c`. End-to-end verified via ssh f-stack-client curl: HTTP 200 / 438-byte HTML body / 100/100 short-conn pass. See `docs/freebsd_13_to_15_upgrade_spec/zh_cn/phase2-M8-execution-log.md`
 - **Phase-2 M9 (2026-06-08)**: enabled both `FF_USE_PAGE_ARRAY=1` + `FF_ZC_SEND=1` combo (P1c, single-pass / 0 bounces, 1-line Makefile change leveraging M7+M8 work); validated co-existence end-to-end (ff_mmap_init 256MB + ipfw2/tcp_bbr init clean + HTTP 200 single curl + 100/100 short-conn). 1000-conn observation: ~3.5× slower than M8 ZC-only with occasional timeout — recorded as M9-followup-F1 for phase-5b perf profiling. See `docs/freebsd_13_to_15_upgrade_spec/zh_cn/phase2-M9-execution-log.md`
 - **Phase-2 M10 (2026-06-08)**: enabled `FF_FLOW_IPIP=1` (P1d, 1 bounce); softened `create_ipip_flow` failure from `rte_exit` to printf warning so primary stays alive on NICs that lack rte_flow IPIP offload (e.g. virtio); GIF tunnel runs in software via FreeBSD `if_gif/in_gif`. End-to-end IPIP tunnel verified: `tools/sbin/ifconfig gif0 create + tunnel + inet` on server side + `ip tunnel add gif0 mode ipip` on Linux f-stack-client side + ping 3/3 received 0% loss RTT 0.29-0.65 ms. example/Makefile auto-skips helloworld_zc target when libfstack.a is built without FF_ZC_SEND. See `docs/freebsd_13_to_15_upgrade_spec/zh_cn/phase2-M10-execution-log.md`
+- **Phase-2 M11/M12/M13 (2026-06-08)**: P2-priority smoke trio — enabled `FF_FLOW_ISOLATE=1` (M11), `FF_FDIR=1` (M12), `FF_LOOPBACK_SUPPORT=1` (M13) each in turn; lib build clean and helloworld primary ALIVE for each. M11 batched the rte_flow soft-fallback for `port_flow_isolate`/`init_flow`/`fdir_add_tcp_flow` (3 sites in `ff_dpdk_if.c`) following the M10 pattern. M13 added one link-only stub `ff_swi_net_excute` to `ff_stub_14_extra.c` (declared in `ff_host_interface.h:92` but never implemented in the tree). See `docs/freebsd_13_to_15_upgrade_spec/zh_cn/phase2-M11-M13-spec.md`
 
 ### 3.2 Ported FreeBSD Subsystems
 

docs/F-Stack_Knowledge_Base_Summary.md

@@ -2,7 +2,7 @@
 
 **Document Version**: 1.0  
 **Generation Date**: 2026-03-20  
-**Content Scope**: F-Stack v1.26 (FreeBSD 15.0 port; upgraded from 13.0 in 2025-2026 — M0~M5 + runtime-fix + rib-fix + Phase-5b NFR-1 PASS; **Phase-2 M6 enabled FF_NETGRAPH+FF_IPFW combo + M7 enabled FF_USE_PAGE_ARRAY + M8 enabled FF_ZC_SEND + M9 PA+ZC combo + M10 enabled FF_FLOW_IPIP, 2026-06-08**) + DPDK 23.11.5 Complete Three-Layer Architecture Knowledge Base  
+**Content Scope**: F-Stack v1.26 (FreeBSD 15.0 port; upgraded from 13.0 in 2025-2026 — M0~M5 + runtime-fix + rib-fix + Phase-5b NFR-1 PASS; **Phase-2 M6 NETGRAPH+IPFW + M7 PAGE_ARRAY + M8 ZC_SEND + M9 PA+ZC + M10 FLOW_IPIP + M11 FLOW_ISOLATE + M12 FDIR + M13 LOOPBACK, 2026-06-08**) + DPDK 23.11.5 Complete Three-Layer Architecture Knowledge Base  
 **Document Location**: `/data/workspace/f-stack/docs/`  
 **Purpose**: Pre-requisite architecture documentation for Spec-Driven Development
 

docs/zh_cn/01-LAYER1-ARCHITECTURE.md

@@ -144,6 +144,7 @@ F-Stack 采用了**完整移植**策略：
 - **Phase-2 M8（2026-06-08）**：默认启用 `FF_ZC_SEND=1`（P1b，1 次打回）；引入 `FSTACK_ZC_MAGIC` sentinel（uio.uio_offset = 0xF8AC2C00F8AC2C00）协议 + 新公开 API `ff_zc_send`，用于区分 ZC mbuf chain 与普通 char buffer；修复 13.0 baseline 遗留 ZC fast-path bug —— 原 `m_uiotombuf` 谓词命中所有 `ff_write`/`ff_writev` 调用，在高压下会静默破坏数据或 `m_demote` GPF。共 8 文件 +85/-4，覆盖 `freebsd/sys/mbuf.h`、`freebsd/kern/uipc_mbuf.c`、`freebsd/kern/sys_generic.c`、`lib/Makefile`、`lib/ff_syscall_wrapper.c`、`lib/ff_api.h`、`lib/ff_api.symlist`、`example/Makefile` + `example/main_zc.c`。通过 ssh f-stack-client curl 端到端验证：HTTP 200 / 438 字节真实 HTML body / 100x 短连 100/100 通过。详见 `docs/freebsd_13_to_15_upgrade_spec/zh_cn/phase2-M8-execution-log.md`
 - **Phase-2 M9（2026-06-08）**：同时启用 `FF_USE_PAGE_ARRAY=1` + `FF_ZC_SEND=1` combo（P1c，单次过 / 0 打回，1 行 Makefile diff 复用 M7+M8 已有代码）；端到端验证共存能力（ff_mmap_init 256MB + ipfw2/tcp_bbr init 干净 + HTTP 200 单次 curl + 100/100 短连）。1000 短连 observation：约 M8 ZC-only 的 3.5 倍耗时且偶发 timeout —— 记为 M9-followup-F1，推迟到 phase-5b 阶段做性能 profiling。详见 `docs/freebsd_13_to_15_upgrade_spec/zh_cn/phase2-M9-execution-log.md`
 - **Phase-2 M10（2026-06-08）**：启用 `FF_FLOW_IPIP=1`（P1d，1 次打回）；将 `create_ipip_flow` 失败从 `rte_exit` 软化为 printf warning，使 primary 在不支持 rte_flow IPIP 卸载的 NIC（如 virtio）上仍可起栈；GIF 隧道走 FreeBSD `if_gif/in_gif` 软件路径。端到端 IPIP 隧道实测：服务端 `tools/sbin/ifconfig gif0 create + tunnel + inet` + 客户端 Linux `ip tunnel add gif0 mode ipip` + ping 3/3 received 0% loss RTT 0.29-0.65 ms。example/Makefile 在 libfstack.a 未启 FF_ZC_SEND 时自动跳过 helloworld_zc target。详见 `docs/freebsd_13_to_15_upgrade_spec/zh_cn/phase2-M10-execution-log.md`
+- **Phase-2 M11/M12/M13（2026-06-08）**：P2 优先级 smoke 三件套 —— 依次启用 `FF_FLOW_ISOLATE=1`（M11）、`FF_FDIR=1`（M12）、`FF_LOOPBACK_SUPPORT=1`（M13）；每个里程碑 lib 编译干净 + helloworld primary 起栈成功。M11 按 M10 模式批量软化了 `port_flow_isolate`/`init_flow`/`fdir_add_tcp_flow` 三处 rte_exit。M13 在 `ff_stub_14_extra.c` 加了一个链接-only stub `ff_swi_net_excute`（声明于 `ff_host_interface.h:92`，但仓库内从未实现）。详见 `docs/freebsd_13_to_15_upgrade_spec/zh_cn/phase2-M11-M13-spec.md`
 
 ### 3.2 FreeBSD 移植的子系统
 

docs/zh_cn/F-Stack_Knowledge_Base_Summary.md

@@ -2,7 +2,7 @@
 
 **文档版本**: 1.0  
 **生成日期**: 2026-03-20  
-**内容范围**: F-Stack v1.26（FreeBSD 15.0 移植；2025-2026 自 13.0 升级 —— M0~M5 + runtime-fix + rib-fix + Phase-5b NFR-1 PASS；**Phase-2 M6 启用 FF_NETGRAPH+FF_IPFW combo + M7 启用 FF_USE_PAGE_ARRAY + M8 启用 FF_ZC_SEND + M9 PA+ZC combo + M10 启用 FF_FLOW_IPIP，2026-06-08**）+ DPDK 23.11.5 完整三层架构知识库  
+**内容范围**: F-Stack v1.26（FreeBSD 15.0 移植；2025-2026 自 13.0 升级 —— M0~M5 + runtime-fix + rib-fix + Phase-5b NFR-1 PASS；**Phase-2 M6 NETGRAPH+IPFW + M7 PAGE_ARRAY + M8 ZC_SEND + M9 PA+ZC + M10 FLOW_IPIP + M11 FLOW_ISOLATE + M12 FDIR + M13 LOOPBACK，2026-06-08**）+ DPDK 23.11.5 完整三层架构知识库  
 **文档位置**: `/data/workspace/f-stack/docs/`  
 **用途**: 规格驱动开发 (Spec-Driven Development) 的前置架构文档
 

lib/Makefile

@@ -37,7 +37,7 @@ FF_KNI=1
 endif
 
 #FF_FLOW_ISOLATE=1
-FF_FDIR=1
+#FF_FDIR=1
 #FF_FLOW_IPIP=1
 # NETGRAPH drivers ipfw
 FF_NETGRAPH=1
@@ -52,7 +52,7 @@ FF_TCPHPTS=1
 FF_EXTRA_TCP_STACKS=1
 
 # TCP/UDP loopback.
-#FF_LOOPBACK_SUPPORT=1
+FF_LOOPBACK_SUPPORT=1
 
 include ${TOPDIR}/mk/kern.pre.mk
 

lib/ff_stub_14_extra.c

@@ -877,5 +877,23 @@ void ipfw_bpf_mtap2(void *arg, u_int len, struct mbuf *m)
     (void)m;
 }
 
+/*
+ * M13 (FF_LOOPBACK_SUPPORT) link-only stub. Declared in
+ * lib/ff_host_interface.h:92 and called from ff_dpdk_if.c:2445
+ * inside the loopback poll loop, but never had a real
+ * implementation in the F-Stack tree (M0~M12 build never had
+ * FF_LOOPBACK_SUPPORT enabled so the symbol was a dead reference).
+ *
+ * The function is intended to drive a software-interrupt-style
+ * network packet executor; in user-space F-Stack the equivalent
+ * work is done inline by ff_dpdk_if main loop, so a no-op stub is
+ * a safe fallback. Smoke testing only — full loopback semantics
+ * may require revisit if a runtime path actually relies on this.
+ */
+void ff_swi_net_excute(void);
+void ff_swi_net_excute(void)
+{
+}
+
 
 /* ===== End of stubs ===== */