Merge pull request 'fleet/ohm: pkgrel=6 — per-series converged (closes ka#29, includes besser#22 / #25 fixes)' (#37) from noether/ohm-pkgrel6-perseries-converged into main

Reviewed-on: marfrit/kernel-agent#37

README.md

@@ -264,8 +264,8 @@ build. `ka-promote` (issue #22) replaced the manual step #1 below as of 2026-05-
 |---|---|---|
 | `ka-import fresnel-fourier <patches> --to board/pinebook-pro` (originally named `ka-promote` in this row) | Authored 3 patches with proper headers/scope tags, pushed to `marfrit/kernel-agent/patches/board/pinebook-pro/` via Gitea contents API as `claude-noether`. | still manual — `ka-import` unimplemented |
 | `ka-promote fresnel` (new — manifest → cumulative.patch + manifest.lock) | n/a (didn't exist) | **automated 2026-05-18, issue #22** |
-| `ka-build fresnel` | On boltzmann: cloned linux v7.0 from kernel.org, ran `makepkg -s --skipchecksums --skippgpcheck` against `marfrit-packages/arch/linux-fresnel-fourier/PKGBUILD`. Native aarch64 (boltzmann is RK3588). One headers-pkg bug discovered (`ln -sr` on missing parent dir) and fixed mid-flight. Repackaged. | still manual — next verb to implement |
-| `ka-sign + push` | scp pkgs hertz → `sudo /opt/herding/bin/marfrit-publish-arch aarch64 <pkg>` per pkg. Script signs with key `92D5E96D8F63C75E4116AA1FF5C8C4603D0D250C`, runs repo-add, rsyncs to nc. | still manual — folded into `ka-build` |
+| `ka-build fresnel` | On boltzmann: cloned linux v7.0 from kernel.org, ran `makepkg -s --skipchecksums --skippgpcheck` against `marfrit-packages/arch/linux-fresnel-fourier/PKGBUILD`. Native aarch64 (boltzmann is RK3588). One headers-pkg bug discovered (`ln -sr` on missing parent dir) and fixed mid-flight. Repackaged. | **automated 2026-05-19, issue #34** — `ka-build <host>` ssh-dispatches makepkg to `build_host.primary`, verifies kernel-agent patches still match the PKGBUILD-side files (b2sum cross-check from `manifest.lock`), and pulls the resulting `*.pkg.tar.zst` back. |
+| `ka-sign + push` | scp pkgs hertz → `sudo /opt/herding/bin/marfrit-publish-arch aarch64 <pkg>` per pkg. Script signs with key `92D5E96D8F63C75E4116AA1FF5C8C4603D0D250C`, runs repo-add, rsyncs to nc. | **folded into `ka-build` 2026-05-19** — `ka-build` scp's each pkg to hertz and runs `marfrit-publish-arch` over ssh. `--skip-publish` flag retained for offline builds. |
 | `ka-install fresnel` (consent-via-action) | `sudo pacman -U /tmp/<pkg>` over LAN scp (HTTPS to nc was throttled by fresnel's wifi). pacman post-transaction hook updated extlinux. mkinitcpio run manually because the standard hook trigger watches `vmlinuz` not `Image`. | still manual — last verb to implement |
 | Bar 1..3 verification | SSH heartbeat OK, `pacman -Q linux-fresnel-fourier` = `7.0-1`, post-reboot cluster0 1.704 GHz / cluster1 2.184 GHz confirmed. | folded into `ka-install` |
 

bin/ka-build

@@ -0,0 +1,199 @@
+#!/usr/bin/env bash
+# ka-build — render PKGBUILD from manifest.lock, build native on host,
+# sign+publish via marfrit-publish-arch on hertz.
+#
+# Phase-1 (issue #34): arch makepkg wrapper. Debian path deferred.
+#
+# Usage:
+#   ka-build <host>
+#   ka-build <host> --packages-repo <path>    # default: ~/src/marfrit-packages
+#   ka-build <host> --dry-run                 # stop after staging, don't makepkg
+#   ka-build <host> --skip-publish            # build only, don't push to hertz
+#
+# Exit codes:
+#   0  success (pkg built + published)
+#   2  missing input (manifest.lock, PKGBUILD, ssh target)
+#   3  patch drift (resolved.sha256 != PKGBUILD-side file sha256)
+#   4  makepkg / sign / publish failure
+#   5  manifest parse error
+
+set -euo pipefail
+
+VERSION=1
+
+die() { echo "ka-build: error: $1" >&2; exit "${2:-1}"; }
+note() { echo "ka-build: $1"; }
+
+# Defaults
+PACKAGES_REPO="${KA_PACKAGES_REPO:-${HOME}/src/marfrit-packages}"
+DRY_RUN=0
+SKIP_PUBLISH=0
+HOST=""
+
+while [ $# -gt 0 ]; do
+    case "$1" in
+        --packages-repo) PACKAGES_REPO="$2"; shift 2 ;;
+        --dry-run) DRY_RUN=1; shift ;;
+        --skip-publish) SKIP_PUBLISH=1; shift ;;
+        --version) echo "ka-build version $VERSION"; exit 0 ;;
+        -h|--help) sed -n '1,30p' "$0" | grep -E '^# ' | sed 's/^# //'; exit 0 ;;
+        -*) die "unknown flag: $1" ;;
+        *) [ -z "$HOST" ] && HOST="$1" || die "extra arg: $1"; shift ;;
+    esac
+done
+
+[ -n "$HOST" ] || die "host is required" 2
+[ -d "$PACKAGES_REPO" ] || die "--packages-repo not found: $PACKAGES_REPO" 2
+
+# Locate kernel-agent repo root (where bin/ + fleet/ live)
+script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(cd "$script_dir/.." && pwd)"
+[ -d "$REPO_ROOT/fleet" ] || die "fleet/ not found relative to $script_dir" 2
+
+manifest="$REPO_ROOT/fleet/${HOST}.yaml"
+[ -f "$manifest" ] || die "no manifest for host '$HOST': $manifest" 2
+
+# Read fields from manifest via python (yaml in bash is masochism)
+py_read() {
+    python3 -c "
+import sys, yaml, os
+m = yaml.safe_load(open('$manifest'))
+keys = '$1'.split('.')
+v = m
+for k in keys:
+    if not isinstance(v, dict) or k not in v: sys.exit('missing key: $1')
+    v = v[k]
+print(v)
+"
+}
+
+PKG_NAME="$(py_read package.name)"
+BASELINE_REF="$(py_read baseline.ref)"
+BUILD_HOST="$(py_read build_host.primary)"
+
+# Locate the most recent ka-promote output
+build_dir_root="${KA_BUILD_DIR:-$REPO_ROOT/build}"
+promote_out="${build_dir_root}/${HOST}/${BASELINE_REF}"
+lock="${promote_out}/manifest.lock"
+cumulative="${promote_out}/cumulative.patch"
+[ -f "$lock" ] || die "no manifest.lock at $lock — run 'ka-promote $HOST' first" 2
+[ -f "$cumulative" ] || die "no cumulative.patch at $cumulative — run 'ka-promote $HOST' first" 2
+
+# Locate the PKGBUILD
+pkg_dir="${PACKAGES_REPO}/arch/${PKG_NAME}"
+pkgbuild="${pkg_dir}/PKGBUILD"
+[ -f "$pkgbuild" ] || die "no PKGBUILD at $pkgbuild (expected from manifest package.name)" 2
+
+note "host=$HOST pkg=$PKG_NAME baseline=$BASELINE_REF build_host=$BUILD_HOST"
+note "PKGBUILD: $pkgbuild"
+note "manifest.lock: $lock"
+
+# Refuse if PKGBUILD-side patches drifted from kernel-agent patches/.
+# manifest.lock.resolved_patches[].sha256 must match PKGBUILD-dir-side
+# files of the same basename. (If a patch is in resolved but missing from
+# PKGBUILD dir, fail loud — operator needs to sync.)
+note "verifying patch consistency between kernel-agent and marfrit-packages..."
+drift=0
+while IFS=$'\t' read -r basename expected_sha; do
+    pkg_side="${pkg_dir}/${basename}"
+    if [ ! -f "$pkg_side" ]; then
+        echo "  MISSING in PKGBUILD dir: $basename" >&2
+        drift=1; continue
+    fi
+    actual_sha=$(sha256sum "$pkg_side" | cut -d' ' -f1)
+    if [ "$actual_sha" != "$expected_sha" ]; then
+        echo "  DRIFT: $basename (expected $expected_sha, got $actual_sha)" >&2
+        drift=1
+    fi
+done < <(python3 -c "
+import yaml, sys, os
+lk = yaml.safe_load(open('$lock'))
+for r in lk['resolved_patches']:
+    bn = os.path.basename(r['include'])
+    print(f\"{bn}\t{r['sha256']}\")
+")
+[ "$drift" -eq 0 ] || die "patches differ between kernel-agent and marfrit-packages — sync first" 3
+note "patches OK ($(python3 -c "import yaml; print(len(yaml.safe_load(open('$lock'))['resolved_patches']))") files)"
+
+if [ "$DRY_RUN" -eq 1 ]; then
+    note "--dry-run: stopping before makepkg"
+    exit 0
+fi
+
+# Stage build dir on the build host via ssh
+note "staging build on ${BUILD_HOST}..."
+remote_stage="/tmp/ka-build-${HOST}-$$"
+ssh "${BUILD_HOST}" "mkdir -p '$remote_stage'"
+rsync -a "${pkg_dir}/" "${BUILD_HOST}:${remote_stage}/"
+
+# Run makepkg natively
+note "running makepkg --syncdeps --noconfirm --cleanbuild on ${BUILD_HOST}..."
+ssh "${BUILD_HOST}" "cd '$remote_stage' && makepkg --syncdeps --noconfirm --cleanbuild --skipchecksums" \
+    || die "makepkg failed on ${BUILD_HOST}" 4
+
+# Fetch built packages
+note "fetching .pkg.tar.zst from ${BUILD_HOST}..."
+local_out="${promote_out}/pkgs"
+mkdir -p "$local_out"
+rsync -av "${BUILD_HOST}:${remote_stage}/*.pkg.tar.zst" "$local_out/" 2>&1 | tail -5
+
+# Compute b2sums
+pkg_b2sum_list=$(cd "$local_out" && for p in *.pkg.tar.zst; do
+    [ -f "$p" ] || continue
+    printf '%s  %s\n' "$(b2sum "$p" | cut -d' ' -f1)" "$p"
+done)
+note "built packages:"
+echo "$pkg_b2sum_list" | sed 's/^/  /'
+
+# Publish via hertz marfrit-publish-arch (unless --skip-publish)
+if [ "$SKIP_PUBLISH" -eq 0 ]; then
+    note "publishing to packages.reauktion.de/arch/aarch64/..."
+    for p in "$local_out"/*.pkg.tar.zst; do
+        [ -f "$p" ] || continue
+        base="$(basename "$p")"
+        scp -q "$p" "hertz:/tmp/${base}" || die "scp to hertz failed: $base" 4
+        ssh hertz "sudo /opt/herding/bin/marfrit-publish-arch aarch64 '/tmp/${base}'" \
+            || die "marfrit-publish-arch failed: $base" 4
+        ssh hertz "rm -f '/tmp/${base}'"
+        note "published: $base"
+    done
+fi
+
+# Update manifest.lock with build receipt (append; don't rewrite the
+# existing fields)
+note "writing build receipt to manifest.lock..."
+python3 - <<PY
+import yaml, os, hashlib
+from datetime import datetime, timezone
+
+lock_path = "$lock"
+out_dir = "$local_out"
+build_host = "$BUILD_HOST"
+skipped = $SKIP_PUBLISH
+
+lk = yaml.safe_load(open(lock_path))
+epoch = os.environ.get("SOURCE_DATE_EPOCH")
+if epoch:
+    built_at = datetime.fromtimestamp(int(epoch), tz=timezone.utc).isoformat()
+else:
+    built_at = datetime.now(tz=timezone.utc).isoformat()
+
+pkgs = []
+for fn in sorted(os.listdir(out_dir)):
+    if not fn.endswith(".pkg.tar.zst"): continue
+    fp = os.path.join(out_dir, fn)
+    b2 = hashlib.blake2b(open(fp, "rb").read()).hexdigest()
+    pkgs.append({"name": fn, "size": os.path.getsize(fp), "b2sum": b2})
+
+lk["build"] = {
+    "built_at": built_at,
+    "built_on_host": build_host,
+    "ka_build_version": $VERSION,
+    "published": (not skipped),
+    "packages": pkgs,
+}
+yaml.dump(lk, open(lock_path, "w"), sort_keys=True, default_flow_style=False)
+print(f"  receipt: {len(pkgs)} package(s), built_at={built_at}, published={not skipped}")
+PY
+
+note "done."

bin/ka-promote

@@ -27,6 +27,7 @@ import argparse
 import glob
 import hashlib
 import os
+import re
 import subprocess
 import sys
 from datetime import datetime, timezone
@@ -37,6 +38,17 @@ VERSION = 1
 SCHEMA_VERSION = 1
 COVER_LETTER = "0000-cover-letter.patch"
 
+# git format-patch trailer: "-- \n<MAJOR>.<MINOR>(.<PATCH>)?\n" at EOF,
+# possibly with trailing blank line(s). Strip from each source patch so
+# that the cumulative is always well-formed regardless of include order.
+# See issue #31.
+_TRAILER_RE = re.compile(rb'\n-- \n\d+\.\d+(?:\.\d+)?\n+\Z')
+
+# Canonical separator emitted between concatenated patches in the
+# cumulative. Trailing blank line keeps patch(1) happy when the next
+# patch starts with "From <sha>".
+_CANONICAL_TRAILER = b'-- \n2.54.0\n\n'
+
 
 def die(msg, code=1):
     print(f"ka-promote: error: {msg}", file=sys.stderr)
@@ -124,11 +136,36 @@ def resolve_includes(includes, patches_root):
     return resolved
 
 
+def strip_trailer(data):
+    """Strip any trailing git format-patch sentinel from a patch.
+
+    Accepts patches in either canonical shape:
+      - WITH trailer: "...\n-- \n2.54.0\n\n"
+      - WITHOUT trailer: "...\n" (already stripped)
+
+    Returns data ending in a single newline so the caller can either
+    append a canonical trailer (mid-cumulative) or leave it bare (last).
+    """
+    stripped = _TRAILER_RE.sub(b'\n', data)
+    if not stripped.endswith(b'\n'):
+        stripped += b'\n'
+    return stripped
+
+
 def write_cumulative(resolved, out_path):
     with open(out_path, "wb") as out:
-        for r in resolved:
+        n = len(resolved)
+        for i, r in enumerate(resolved):
             with open(r["src"], "rb") as src:
-                out.write(src.read())
+                data = src.read()
+            data = strip_trailer(data)
+            out.write(data)
+            # Mid-cumulative patches need a separator so patch(1) knows
+            # where they end and the next "From <sha>" begins. Last
+            # patch stays bare — a trailing orphan sentinel reads as
+            # the start of a malformed new patch at EOF (issue #31).
+            if i != n - 1:
+                out.write(_CANONICAL_TRAILER)
     with open(out_path, "rb") as f:
         b2 = hashlib.blake2b(f.read()).hexdigest()
     size = os.path.getsize(out_path)

fleet/ampere.yaml

@@ -53,12 +53,19 @@ includes:
   - board/coolpi-cm5-genbook/0005-arm64-dts-rockchip-rk3588-coolpi-cm5-genbook-Enable-USB-C-PD-charging-via-FUSB302.patch
   - board/coolpi-cm5-genbook/0008-arm64-dts-rockchip-rk3588-coolpi-cm5-genbook-Add-lid-switch-and-USB3-PHY-lane-config.patch
   - board/coolpi-cm5-genbook/0011-arm64-dts-rockchip-rk3588-coolpi-cm5-genbook-wire-internal-microphone.patch
+  # VP9 enablement for RK3588 rkvdec (issue #12, closed 2026-05-18).
+  # Cherry-picked from D.V.A.B. Sarma's add-rkvdec-vdpu381-vp9-v8 branch
+  # at github.com/dvab-sarma/android_kernel_rk_opi. Bit-exact HW==SW==libva
+  # verified at -ss 30 on bbb_60s_720p.vp9.webm via all three decode paths
+  # (kdirect / SW / libva); sha c8624d7c42db66525f53a02a515bc38d0a17ef39f692660cc7bebb1e2d2e1b48.
+  # Apply order is STRICT (0003 depends on the rkvdec-vp9-common refactor
+  # added in 0002, which depends on the helper rename in 0001).
+  # See patches/driver/media/README.md for provenance + removal criteria.
+  - driver/media/0001-rkvdec-vp9-rename-get_ref_buf-to-get_ref_buf_vp9.patch
+  - driver/media/0002-rkvdec-move-vp9-functions-to-common-file.patch
+  - driver/media/0003-rkvdec-add-vp9-support-for-vdpu381-variant.patch
 
 # Explicitly NOT included this round (tracked for later sprints):
-#   - VP9 enablement for RK3588 rkvdec (issue #6 ask 2). /dev/video0 only
-#     advertises S265 + S264 today; vainfo lists 9 profiles, target is
-#     10. Requires identifying the VDPU381/383 patch chain + possible
-#     DTS additions. RFC-stage work, scope unclear until research lands.
 #   - AV1 decoder integration (issue #6 ask 3). Kernel side is fine
 #     (/dev/video4 advertises AV1F). Backend libva-v4l2-request-fourier
 #     needs iter39 for a third fd. Backend work, not kernel.

fleet/ohm.yaml

@@ -1,6 +1,6 @@
 # kernel-agent manifest for ohm (PineTab2 / Rockchip RK3566 + BES2600 SDIO WiFi/BT)
 #
-# Status: scaffolding from 2026-05-16. Patches/scopes are mirrored;
+# Status: scaffolding from 2026-05-16; per-series patchset converged 2026-05-21 (pkgrel=6). Patches/scopes are mirrored;
 # the build pipeline (cumulative-patch generation, makepkg invocation,
 # sign+publish) still relies on the hand-managed flow in
 # boltzmann:~/src/besser/marfrit-besser/danctnix-besser-pkgbuild/kernel/.
@@ -32,6 +32,13 @@ baseline:
 # mixed-prefix headers (a/drivers/staging/bes2600/...  b/bes2600/...).
 # They do NOT apply cleanly against the linux-pinetab2 baseline.
 #
+
+# 2026-05-21 update: per-series reconstruction (besser#22) completed
+# 2026-05-21; pkgrel=6 (srcversion 0E16463F) on ohm soak-passed with
+# the bounce-buffer + join-confirm-reset additions. The per-series
+# manifest below is the authoritative set; cumulative-c5x-danctnix
+# remains as historical fallback only.
+#
 # Until the per-series mirrors are reconstructed (kernel-agent followup
 # issue), the bes2600 driver scope is satisfied by a single-file
 # cumulative captured from the working hand-managed
@@ -48,10 +55,19 @@ includes:
   # Runtime no-op as long as the config has CONFIG_SHADOW_CALL_STACK=n
   # (current ohm setting). Kept in the manifest for the day SCS gets
   # re-enabled. See reference_arm64_scs_arm_neon_gcc15 memory.
-  - arch/arm64/xor-neon-ffixed-x18-scs-build-fix-danctnix/
+  - arch/arm64/scs-arm-neon-build-fix/
   # close besser#18 — pending_record_lock SOFTIRQ-safe -> -unsafe inversion.
   # Mirror of marfrit/bes2600-dkms#11 (d95453c). 5-site spin_lock -> _bh.
   - driver/bes2600/queue-pending-record-lock-bh-danctnix/
+  # bounce-buffer fix for SDIO TX DMA OOB (KFENCE-detected on pkgrel=4 soak);
+  # the per-series mirror of marfrit/bes2600-dkms bes2600/tx-sdio-dma-oob.
+  # cumulative-c5x-danctnix did NOT include this — it was the regression
+  # surfaced during the per-series reconstruction.
+  - driver/bes2600/tx-sdio-dma-oob-danctnix/
+  # close besser#25 — wsm_reset + serialised unjoin on JOIN reject.
+  # cw1200 ancestor port (drivers/net/wireless/st/cw1200/sta.c:1339-1344)
+  # with bes2600-specific PASSIVE-gate compensation.  pkgrel=6 verified.
+  - driver/bes2600/join-confirm-reset-danctnix/
 
 # Explicitly NOT included (decision logged):
 #   - debian-copyright-fsf-address: Debian packaging metadata, not kernel

patches/arch/arm64/scs-arm-neon-build-fix/0001-arm64-xor-neon-ffixed-x18-build-fix.patch

@@ -22,7 +22,7 @@ diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile
 index 1234567..2345678 100644
 --- a/arch/arm64/lib/Makefile
 +++ b/arch/arm64/lib/Makefile
-@@ -9,6 +9,11 @@ ifeq ($(CONFIG_KERNEL_MODE_NEON), y)
+@@ -9,6 +9,10 @@ ifeq ($(CONFIG_KERNEL_MODE_NEON), y)
  obj-$(CONFIG_XOR_BLOCKS)	+= xor-neon.o
  CFLAGS_xor-neon.o		+= $(CC_FLAGS_FPU)
  CFLAGS_REMOVE_xor-neon.o	+= $(CC_FLAGS_NO_FPU)
@@ -34,6 +34,3 @@ index 1234567..2345678 100644
  endif
  
  lib-$(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) += uaccess_flushcache.o
--- 
-2.54.0
-

patches/arch/arm64/xor-neon-ffixed-x18-scs-build-fix-danctnix/README.md

@@ -1,20 +0,0 @@
-# xor-neon-ffixed-x18-scs-build-fix-danctnix — GCC 15.2.1 build fix
-
-Restores `-ffixed-x18` for `arch/arm64/lib/xor-neon.c` when
-`CONFIG_SHADOW_CALL_STACK=y`. GCC 15.2.1 enforces that
-`-fsanitize=shadow-call-stack` requires `-ffixed-x18` inside
-arm_neon.h's `#pragma GCC target()` push/pop blocks; CC_FLAGS_REMOVE
-strips the kernel-wide `-ffixed-x18` for xor-neon.o and CC_FLAGS_FPU
-does not restore it.
-
-**Note on current ohm config**: `linux-pinetab2-danctnix-besser`
-config has `# CONFIG_SHADOW_CALL_STACK is not set` as of pkgrel=3,
-which makes this patch a runtime no-op (`$(if $(CONFIG_SHADOW_CALL_STACK),
--ffixed-x18)` evaluates to nothing). Patch is kept in the manifest as
-belt-and-suspenders for the day SCS gets re-enabled (tracked in
-besser issue for GCC fix monitoring).
-
-See [[reference_arm64_scs_arm_neon_gcc15]] for the full toolchain
-analysis. This patch is the upstream-friendly Makefile fix; the
-config-side `SHADOW_CALL_STACK=n` workaround is the immediate
-runtime mitigation. Both are present in pkgrel=3 for safety.

patches/driver/bes2600/join-confirm-reset-danctnix/0001-bes2600-reset-firmware-state-on-wsm_join_confirm-fai.patch

@@ -0,0 +1,131 @@
+From 3d833f8ccf31895a2ce7bf4fd4ef839e653b29bb Mon Sep 17 00:00:00 2001
+From: Markus Fritsche <fritsche.markus@gmail.com>
+Date: Thu, 21 May 2026 09:25:12 +0200
+Subject: [PATCH 22/22] bes2600: reset firmware state on wsm_join_confirm
+ failure
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+When wsm_join_confirm() returns status != WSM_STATUS_SUCCESS (ret 1),
+the driver cleared its bookkeeping but did not reset the firmware
+interface, leaving it in an intermediate post-rejection state.  A rapid
+second JOIN attempt (e.g. wpa_supplicant retrying after the
+PREV_AUTH_NOT_VALID deauth that mac80211 emits to clean up) hits an
+inconsistent firmware context, causing bes2600_sdio_read_rx_batch to
+return SDIO error which cascades into wifi_force_close:
+
+  wsm_join_confirm ret 1
+  deauthenticating from <bssid> by local choice (Reason: 2=PREV_AUTH_NOT_VALID)
+  [~10 min later]
+  bes2600_sdio_read_rx_batch sdio read error
+  WARNING: at bes2600_tx_loop_set_enable / bes2600_chrdev_wifi_force_close
+
+Two additions to the failure path in bes2600_join_work():
+
+1. wsm_reset (WSM_REQ_ID_RESET, 0x000A) with reset_statistics=false.
+   This returns the firmware to IDLE so the next association attempt
+   starts from a known-clean state.  bes2600_unjoin_work() performs the
+   same reset, but gates it on join_status != PASSIVE; after a failed
+   JOIN join_status stays PASSIVE, so that path never fires — call
+   wsm_reset directly here instead.
+
+   Contract: wsm_reset takes only wsm_cmd_lock (not conf_lock, not
+   wsm_oper_lock).  wsm_oper_unlock was already called inside
+   wsm_join_confirm() before wsm_join() returned -EINVAL, so there is
+   no re-entrancy hazard.  conf_lock is held at this call site, which is
+   compatible with wsm_reset's locking requirements.
+
+2. queue_work(workqueue, &priv->unjoin_work) instead of direct
+   wsm_unlock_tx().  Serialises the next association attempt through
+   the workqueue so it cannot race against lingering firmware-side
+   effects of the failure.  If unjoin_work is already queued, release
+   TX immediately (matching cw1200 ancestor sta.c:1344 comment "Tx lock
+   still held, unjoin will clear it.").
+
+Ancestor reference: drivers/net/wireless/st/cw1200/sta.c, function
+cw1200_join_work(), lines 1339-1344.  cw1200 queues unjoin_work on join
+failure for the same reason.  bes2600 needs the direct wsm_reset in
+addition because its unjoin_work has the join_status gate that cw1200's
+cw1200_do_unjoin() does not.
+
+Signed-off-by: Claude (noether) <claude@reauktion.de>
+---
+ bes2600/sta.c | 47 +++++++++++++++++++++++++++++++++++++++++++----
+ 1 file changed, 43 insertions(+), 4 deletions(-)
+
+diff --git a/drivers/staging/bes2600/sta.c b/drivers/staging/bes2600/sta.c
+index 476d875..bf86835 100644
+--- a/drivers/staging/bes2600/sta.c
++++ b/drivers/staging/bes2600/sta.c
+@@ -2225,9 +2225,10 @@ void bes2600_join_work(struct work_struct *work)
+ 	struct wsm_template_frame probe_tmp = {
+ 		.frame_type = WSM_FRAME_TYPE_PROBE_REQUEST,
+ 	};
+-	/*struct wsm_reset reset = {
+-		.reset_statistics = true,
+-	};*/
++	struct wsm_reset join_fail_reset = {
++		.reset_statistics = false,
++	};
++	bool join_failed = false;
+ 
+ 
+ 	BUG_ON(queueId >= 4);
+@@ -2410,6 +2411,33 @@ void bes2600_join_work(struct work_struct *work)
+ #endif /*CONFIG_BES2600_TESTMODE*/
+ 			cancel_delayed_work_sync(&priv->join_timeout);
+ 			bes2600_pwr_clear_busy_event(priv->hw_priv, BES_PWR_LOCK_ON_JOIN);
++			/*
++			 * Firmware rejected WSM_JOIN (wsm_join_confirm ret 1).
++			 * Issue wsm_reset so the firmware returns to a clean
++			 * IDLE state before the next association attempt.
++			 *
++			 * Without this reset the firmware sits in an
++			 * intermediate post-reject state.  A rapid second
++			 * JOIN (e.g. wpa_supplicant retrying after the
++			 * PREV_AUTH_NOT_VALID deauth that follows) hits an
++			 * inconsistent firmware context, causing
++			 * bes2600_sdio_read_rx_batch to return SDIO error
++			 * which cascades into wifi_force_close.
++			 *
++			 * cw1200 ancestor (drivers/net/wireless/st/cw1200/
++			 * sta.c:1339) queues unjoin_work on join failure for
++			 * the same reason; bes2600_unjoin_work gates its
++			 * wsm_reset on join_status != PASSIVE, so after a
++			 * failed JOIN (join_status stays PASSIVE) that path
++			 * never fires — call wsm_reset directly here instead.
++			 *
++			 * Contract: wsm_reset takes only wsm_cmd_lock; safe
++			 * to call while conf_lock is held.  wsm_oper_unlock
++			 * was already called in wsm_join_confirm() before
++			 * wsm_join() returned the error.
++			 */
++			WARN_ON(wsm_reset(hw_priv, &join_fail_reset, priv->if_id));
++			join_failed = true;
+ 		} else {
+ 			/* Upload keys */
+ #ifdef CONFIG_BES2600_TESTMODE
+@@ -2434,7 +2462,18 @@ void bes2600_join_work(struct work_struct *work)
+ 	up(&hw_priv->conf_lock);
+ 	if (bss)
+ 		cfg80211_put_bss(hw_priv->hw->wiphy, bss);
+-	wsm_unlock_tx(hw_priv);
++	/*
++	 * On join failure: queue unjoin_work so the next association
++	 * attempt is serialised after any lingering cleanup, matching
++	 * cw1200 sta.c:1344 "Tx lock still held, unjoin will clear it."
++	 * If unjoin_work is already queued, release TX immediately.
++	 */
++	if (join_failed) {
++		if (queue_work(hw_priv->workqueue, &priv->unjoin_work) <= 0)
++			wsm_unlock_tx(hw_priv);
++	} else {
++		wsm_unlock_tx(hw_priv);
++	}
+ }
+ 
+ void bes2600_join_timeout(struct work_struct *work)
+-- 
+2.54.0
+

patches/driver/bes2600/join-confirm-reset-danctnix/README.md

@@ -0,0 +1,46 @@
+# bes2600/join-confirm-reset-danctnix
+
+Danctnix-flavor patch closing besser#25 (wsm_join_confirm failure cascade).
+
+## What it does
+
+When firmware returns status 1 on a JOIN command (`wsm_join_confirm ret 1`),
+add a direct `wsm_reset(...)` call so the firmware returns to a clean IDLE
+state, plus `queue_work(workqueue, &priv->unjoin_work)` for serialisation of
+the next association attempt.
+
+## Why it's a fork-divergence fix
+
+`cw1200_join_work()` (cw1200 ancestor, `drivers/net/wireless/st/cw1200/sta.c:1339-1344`)
+queues `unjoin_work` on join failure: `cw1200_do_unjoin()` calls `wsm_reset`
+when `join_status == STA`.
+
+bes2600's `bes2600_unjoin_work()` gates the same `wsm_reset` on
+`join_status != PASSIVE`. After a failed JOIN, `join_status` stays PASSIVE
+(only set to STA on success) — queuing `unjoin_work` alone is insufficient
+on bes2600. The danctnix variant carries a direct `wsm_reset` in the
+failure path *and* the queue_work serialisation.
+
+## Observable effects (pkgrel=6 soak)
+
+Beyond closing the cascade (besser#25 acceptance), this patch also
+collapsed the periodic ~600 ms latency jitter on ohm:
+
+| | pkgrel=5 | pkgrel=6 |
+|---|---|---|
+| max RTT | 612 ms | 13.9 ms |
+| mdev | 103.5 ms | 1.55 ms |
+
+The bgscan-driven roam-attempt to a 5 GHz BSSID followed by `wsm_join`
+reject was briefly stalling TX every minute even when the cascade did
+not fire.
+
+## Upstream
+
+- besser issue: marfrit/besser#25
+- bes2600-dkms branch (Mobian flavor): bes2600/wsm-join-confirm-reset
+  (PR #12 against `cleanups`)
+- bes2600-dkms branch (danctnix flavor): bes2600/join-confirm-failure-reset
+  (top commit `3d833f8`)
+- shipped as patch 0022 in danctnix-besser-pkgbuild kernel/ (pkgrel=6,
+  srcversion 0E16463FA8D85F4704DE93F)

patches/driver/bes2600/queue-pending-record-lock-bh-danctnix/0001-bes2600-take-pending-record-lock-with-bh.patch

@@ -116,3 +116,6 @@ index e6cf072..0cf7ce1 100644
  
          if (atomic_read(&hw_priv->bh_rx) > 0)
  		wake_up(&hw_priv->bh_wq);
+-- 
+2.54.0
+

patches/driver/bes2600/scan-filter-5ghz/0001-bes2600-filter-5-GHz-scans-at-the-driver-boundary.patch

@@ -0,0 +1,168 @@
+From 093a5038b8b68f316d976b7cb69609ca7f24f322 Mon Sep 17 00:00:00 2001
+From: Markus Fritsche <fritsche.markus@gmail.com>
+Date: Mon, 18 May 2026 11:27:40 +0200
+Subject: [PATCH 1/2] bes2600: filter 5 GHz scans at the driver boundary
+ (besser#1)
+
+The BES2600 firmware refuses WSM start-scan for 5 GHz with status 2
+("rejected by policy").  This shows up in dmesg as the recurring
+
+    wsm_generic_confirm failed for request 0x0007.
+    [SCAN] Scan failed (-22).
+
+pattern (besser issue #1, ~14-16/h on ohm/PineTab2 baseline).
+
+Trace shows every reject is the second of a back-to-back pair: mac80211
+splits multi-band hw_scan requests per band when the driver does not
+set IEEE80211_HW_SINGLE_SCAN_ON_ALL_BANDS (we don't), then re-invokes
+drv_hw_scan from __ieee80211_scan_completed for each subsequent band.
+The 2.4 GHz iteration succeeds; the 5 GHz iteration is what the
+firmware rejects.  See ieee80211_prep_hw_scan in net/mac80211/scan.c
+for the loop, and the existing memory reference_bes2600_5ghz_scan_reject
+for the firmware behaviour.
+
+The 056a71a defer-on-reject patch already in this tree handles the
+BT-A2DP-coex branch and the consecutive-reject backoff, but it cannot
+prevent the per-band-loop reject: by the time defer_should_scan is
+consulted, the per-band call is already in flight, and the reject_count
+gets reset on every successful 2.4 GHz scan in between (which is
+~36% of attempts), so the threshold never trips.
+
+The fix: refuse the 5 GHz iteration upfront in bes2600_hw_scan.  The
+2.4 GHz scan still runs normally.  The 5 GHz portion is reported as
+aborted to userspace -- same outcome as today, minus the dmesg storm
+and the wsm_generic_confirm WARN cascade.
+
+5 GHz band registration is intentionally left in place: direct-BSSID
+association to a known 5 GHz AP still works (no scan is needed for
+that path), and a future firmware update that fixes the scan behaviour
+should not be foreclosed by changing band advertisement.
+
+Contract: per include/net/mac80211.h ieee80211_ops.hw_scan, a negative
+return aborts the scan without requiring ieee80211_scan_completed().
+-EOPNOTSUPP is the semantically accurate code (operation is legal,
+driver can't service it on this band today).
+
+Phase 3 evidence:
+- baseline N=3: rate ~14.3-23.6/h converged at 14.3/h (matches OP)
+- back-to-back scan gap: 6/6 rejected pairs <200us, 1/1 successful
+  pair was 114ms (single-band-only, no 5 GHz leg)
+- defer log fires: 0/9 in 30-min window (056a71a structurally bypassed)
+
+Predicted Phase 7 delta: Pattern A 14/h -> 0/h.
+---
+ bes2600/scan.c | 22 ++++++++++++++++++++++
+ 1 file changed, 22 insertions(+)
+
+diff --git a/drivers/staging/bes2600/scan.c b/drivers/staging/bes2600/scan.c
+index fb1d298..a81afb6 100644
+--- a/drivers/staging/bes2600/scan.c
++++ b/drivers/staging/bes2600/scan.c
+@@ -238,6 +238,28 @@ int bes2600_hw_scan(struct ieee80211_hw *hw,
+ 	/* Scan when P2P_GO corrupt firmware MiniAP mode */
+ 	if (priv->join_status == BES2600_JOIN_STATUS_AP)
+ 		return -EOPNOTSUPP;
++
++	/*
++	 * Firmware refuses WSM start-scan for 5 GHz with status 2 ("rejected
++	 * by policy"); see besser issue #1.  mac80211 splits multi-band
++	 * hw_scan requests per-band when the driver does not set
++	 * IEEE80211_HW_SINGLE_SCAN_ON_ALL_BANDS (we don't -- see
++	 * ieee80211_hw_set() calls in bes2600_main.c), so each per-band call
++	 * has req->channels[] from one band only (see ieee80211_prep_hw_scan
++	 * in net/mac80211/scan.c).  Refuse the 5 GHz iteration at the driver
++	 * boundary so userspace gets a clean aborted-scan for that portion
++	 * rather than waiting for the firmware reject to cascade up.  5 GHz
++	 * band registration stays intact so direct-BSSID association to a
++	 * known 5 GHz AP still works (no scan needed for that path).
++	 *
++	 * Contract: per include/net/mac80211.h struct ieee80211_ops.hw_scan
++	 * documentation, a negative return aborts the scan without requiring
++	 * ieee80211_scan_completed().
++	 */
++	if (req->n_channels > 0 &&
++	    req->channels[0]->band == NL80211_BAND_5GHZ)
++		return -EOPNOTSUPP;
++
+ #if 0
+ 	if (work_pending(&priv->offchannel_work) ||
+ 			(hw_priv->roc_if_id != -1)) {
+-- 
+2.54.0
+
+
+From 8cd10f487c8144d462a510812ba0fa717b3e24df Mon Sep 17 00:00:00 2001
+From: Markus Fritsche <fritsche.markus@gmail.com>
+Date: Mon, 18 May 2026 15:56:34 +0200
+Subject: [PATCH 2/2] bes2600: scan-filter-5ghz: allow targeted single-channel
+ scans (besser#1 follow-up)
+
+The original Patch I refused EVERY 5 GHz scan request unconditionally
+(req->n_channels > 0 && band == NL80211_BAND_5GHZ).  This eliminated
+the Pattern A storm but also broke 5 GHz association entirely:
+NM / wpa_supplicant iterates a freq_list when a connection profile
+specifies 802-11-wireless.band=a, issuing per-frequency single-channel
+scans to find the BSS before associating.  Those single-channel scans
+were also refused by our guard, so the BSS was never seen and
+'Wi-Fi network could not be found' was the only outcome.
+
+Tighten the guard: refuse only multi-channel 5 GHz scans (n_channels
+> 1), which is the per-band-sweep pattern mac80211 issues internally
+and the only one that triggers the firmware storm at the per-band
+loop boundary.  Single-channel 5 GHz scans pass through to firmware,
+which generally accepts them -- and when they happen to be rejected,
+the failure is isolated and doesn't cascade.
+
+Verified on ohm with pkgrel=3 (srcversion BEB625FA7443171EA8D55F7):
+  - Pattern A count since boot: 0 (Phase 7 prediction still holds)
+  - iw dev wlan0 scan freq 5180          -> allowed
+  - iw dev wlan0 scan freq 5180 5200 ... -> refused -EOPNOTSUPP
+  - NM 'nmcli connection up' with band=a -> associated to BSSID
+    c0:25:06:e6:5b:33 on 5240 MHz / ch.48 in ~1 second
+  - TX bitrate 150 Mbit/s MCS 7 40MHz short-GI (vs 72.2 Mbit/s
+    HT20 on 2.4 GHz) -- ~2x throughput recovered
+
+The change is a single byte (> 0 -> > 1) plus comment update; the
+test confirmation above is what motivates it.
+
+Refs: besser#1 (closed but tracked for follow-up like this), original
+Patch I sha 093a503.
+---
+ bes2600/scan.c | 16 ++++++++++++----
+ 1 file changed, 12 insertions(+), 4 deletions(-)
+
+diff --git a/drivers/staging/bes2600/scan.c b/drivers/staging/bes2600/scan.c
+index a81afb6..497523b 100644
+--- a/drivers/staging/bes2600/scan.c
++++ b/drivers/staging/bes2600/scan.c
+@@ -248,15 +248,23 @@ int bes2600_hw_scan(struct ieee80211_hw *hw,
+ 	 * has req->channels[] from one band only (see ieee80211_prep_hw_scan
+ 	 * in net/mac80211/scan.c).  Refuse the 5 GHz iteration at the driver
+ 	 * boundary so userspace gets a clean aborted-scan for that portion
+-	 * rather than waiting for the firmware reject to cascade up.  5 GHz
+-	 * band registration stays intact so direct-BSSID association to a
+-	 * known 5 GHz AP still works (no scan needed for that path).
++	 * rather than waiting for the firmware reject to cascade up.
++	 *
++	 * Only the multi-channel case is refused (n_channels > 1): that's
++	 * the per-band-sweep pattern mac80211 issues internally and the
++	 * one that triggers the firmware storm at the per-band loop
++	 * boundary.  Single-channel 5 GHz scans (BSS verification, NM's
++	 * per-freq iteration when 802-11-wireless.band=a is set) pass
++	 * through to firmware, which generally accepts them since the
++	 * storm is the back-to-back per-band issue, not a blanket 5 GHz
++	 * reject.  This preserves 5 GHz association via the
++	 * "wpa_supplicant iterates freq_list per channel" path.
+ 	 *
+ 	 * Contract: per include/net/mac80211.h struct ieee80211_ops.hw_scan
+ 	 * documentation, a negative return aborts the scan without requiring
+ 	 * ieee80211_scan_completed().
+ 	 */
+-	if (req->n_channels > 0 &&
++	if (req->n_channels > 1 &&
+ 	    req->channels[0]->band == NL80211_BAND_5GHZ)
+ 		return -EOPNOTSUPP;
+ 
+-- 
+2.54.0
+

patches/driver/media/0001-rkvdec-vp9-rename-get_ref_buf-to-get_ref_buf_vp9.patch

@@ -0,0 +1,48 @@
+From 9ddcae54a171f2fc7742e92e03b1478d87ae4bbb Mon Sep 17 00:00:00 2001
+From: Venkata Atchuta Bheemeswara Sarma Darbha <vdarbha0473@gmail.com>
+Date: Sat, 17 Jan 2026 14:27:22 -0600
+Subject: [PATCH 1/3] media: rkvdec: vp9: Changing get_ref_buf function name to
+ get_ref_buf_vp9
+
+This change is in preparation for the upcoming commits and to denote that this function is not to be confused with the similar function found in rkvdec's hevc.
+
+Change-Id: I934684778c375c6960a19989a702be44655c55d6
+Signed-off-by: Venkata Atchuta Bheemeswara Sarma Darbha <vdarbha0473@gmail.com>
+(cherry picked from commit f60174f07d9c56e7499ca3111d0999e26444cdfd)
+---
+ drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c | 10 +++++-----
+ 1 file changed, 5 insertions(+), 5 deletions(-)
+
+diff --git a/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c
+index e4cdd2122873..bab2e9c83d06 100644
+--- a/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c
++++ b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c
+@@ -349,7 +349,7 @@ static void init_probs(struct rkvdec_ctx *ctx,
+ }
+ 
+ static struct rkvdec_decoded_buffer *
+-get_ref_buf(struct rkvdec_ctx *ctx, struct vb2_v4l2_buffer *dst, u64 timestamp)
++get_ref_buf_vp9(struct rkvdec_ctx *ctx, struct vb2_v4l2_buffer *dst, u64 timestamp)
+ {
+ 	struct v4l2_m2m_ctx *m2m_ctx = ctx->fh.m2m_ctx;
+ 	struct vb2_queue *cap_q = &m2m_ctx->cap_q_ctx.q;
+@@ -489,12 +489,12 @@ static void config_registers(struct rkvdec_ctx *ctx,
+ 
+ 	dec_params = run->decode_params;
+ 	dst = vb2_to_rkvdec_decoded_buf(&run->base.bufs.dst->vb2_buf);
+-	ref_bufs[0] = get_ref_buf(ctx, &dst->base.vb, dec_params->last_frame_ts);
+-	ref_bufs[1] = get_ref_buf(ctx, &dst->base.vb, dec_params->golden_frame_ts);
+-	ref_bufs[2] = get_ref_buf(ctx, &dst->base.vb, dec_params->alt_frame_ts);
++	ref_bufs[0] = get_ref_buf_vp9(ctx, &dst->base.vb, dec_params->last_frame_ts);
++	ref_bufs[1] = get_ref_buf_vp9(ctx, &dst->base.vb, dec_params->golden_frame_ts);
++	ref_bufs[2] = get_ref_buf_vp9(ctx, &dst->base.vb, dec_params->alt_frame_ts);
+ 
+ 	if (vp9_ctx->last.valid)
+-		last = get_ref_buf(ctx, &dst->base.vb, vp9_ctx->last.timestamp);
++		last = get_ref_buf_vp9(ctx, &dst->base.vb, vp9_ctx->last.timestamp);
+ 	else
+ 		last = dst;
+ 
+-- 
+2.54.0
+

patches/driver/media/0002-rkvdec-move-vp9-functions-to-common-file.patch

@@ -0,0 +1,387 @@
+From c5063d93e0e6011abe91418a98ed7c7550f0391b Mon Sep 17 00:00:00 2001
+From: Venkata Atchuta Bheemeswara Sarma Darbha <vdarbha0473@gmail.com>
+Date: Sat, 17 Jan 2026 14:37:07 -0600
+Subject: [PATCH 2/3] media: rkvdec: Move vp9 functions to common file This is
+ a preparation commit to add support for new variants of the decoder.
+
+The functions will later be shared with vdpu381 (rk3588).
+
+Change-Id: Ib9b78331fb6eb0e3a607b06fd5138fc741b2c9c0
+Signed-off-by: Venkata Atchuta Bheemeswara Sarma Darbha <vdarbha0473@gmail.com>
+(cherry picked from commit e87662ca32e88ebb910f6cfc1c71096d5d7bc063)
+---
+ .../media/platform/rockchip/rkvdec/Makefile   |   1 +
+ .../rockchip/rkvdec/rkvdec-vp9-common.c       |  77 +++++++++++
+ .../rockchip/rkvdec/rkvdec-vp9-common.h       |  95 +++++++++++++
+ .../platform/rockchip/rkvdec/rkvdec-vp9.c     | 125 +-----------------
+ 4 files changed, 174 insertions(+), 124 deletions(-)
+ create mode 100644 drivers/media/platform/rockchip/rkvdec/rkvdec-vp9-common.c
+ create mode 100644 drivers/media/platform/rockchip/rkvdec/rkvdec-vp9-common.h
+
+diff --git a/drivers/media/platform/rockchip/rkvdec/Makefile b/drivers/media/platform/rockchip/rkvdec/Makefile
+index e629d571e4d8..2bbd67b2db11 100644
+--- a/drivers/media/platform/rockchip/rkvdec/Makefile
++++ b/drivers/media/platform/rockchip/rkvdec/Makefile
+@@ -12,4 +12,5 @@ rockchip-vdec-y += \
+ 		   rkvdec-vdpu381-hevc.o \
+ 		   rkvdec-vdpu383-h264.o \
+ 		   rkvdec-vdpu383-hevc.o \
++		   rkvdec-vp9-common.o \
+ 		   rkvdec-vp9.o
+diff --git a/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9-common.c b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9-common.c
+new file mode 100644
+index 000000000000..93023737c1ed
+--- /dev/null
++++ b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9-common.c
+@@ -0,0 +1,77 @@
++// SPDX-License-Identifier: GPL-2.0
++/*
++ * Rockchip video decoder VP9 common functions
++ *
++ * Copyright (C) 2019 Collabora, Ltd.
++ *	Boris Brezillon <boris.brezillon@collabora.com>
++ * Copyright (C) 2021 Collabora, Ltd.
++ *	Andrzej Pietrasiewicz <andrzej.p@collabora.com>
++ *
++ * Copyright (C) 2016 Rockchip Electronics Co., Ltd.
++ *	Alpha Lin <Alpha.Lin@rock-chips.com>
++ */
++#include <linux/v4l2-common.h>
++#include <media/v4l2-h264.h>
++#include <media/v4l2-mem2mem.h>
++
++#include "rkvdec.h"
++#include "rkvdec-vp9-common.h"
++
++void write_coeff_plane(const u8 coef[6][6][3], u8 *coeff_plane)
++{
++	unsigned int idx = 0, byte_count = 0;
++	int k, m, n;
++	u8 p;
++
++	for (k = 0; k < 6; k++) {
++		for (m = 0; m < 6; m++) {
++			for (n = 0; n < 3; n++) {
++				p = coef[k][m][n];
++				coeff_plane[idx++] = p;
++				byte_count++;
++				if (byte_count == 27) {
++					idx += 5;
++					byte_count = 0;
++				}
++			}
++		}
++	}
++}
++
++struct rkvdec_decoded_buffer *
++get_ref_buf_vp9(struct rkvdec_ctx *ctx, struct vb2_v4l2_buffer *dst, u64 timestamp)
++{
++	struct v4l2_m2m_ctx *m2m_ctx = ctx->fh.m2m_ctx;
++	struct vb2_queue *cap_q = &m2m_ctx->cap_q_ctx.q;
++	struct vb2_buffer *buf;
++
++	/*
++	 * If a ref is unused or invalid, address of current destination
++	 * buffer is returned.
++	 */
++	buf = vb2_find_buffer(cap_q, timestamp);
++	if (!buf)
++		buf = &dst->vb2_buf;
++
++	return vb2_to_rkvdec_decoded_buf(buf);
++}
++
++dma_addr_t get_mv_base_addr(struct rkvdec_decoded_buffer *buf)
++{
++	unsigned int aligned_pitch, aligned_height, yuv_len;
++
++	aligned_height = round_up(buf->vp9.height, 64);
++	aligned_pitch = round_up(buf->vp9.width * buf->vp9.bit_depth, 512) / 8;
++	yuv_len = (aligned_height * aligned_pitch * 3) / 2;
++
++	return vb2_dma_contig_plane_dma_addr(&buf->base.vb.vb2_buf, 0) +
++	       yuv_len;
++}
++
++void update_dec_buf_info(struct rkvdec_decoded_buffer *buf,
++				const struct v4l2_ctrl_vp9_frame *dec_params)
++{
++	buf->vp9.width = dec_params->frame_width_minus_1 + 1;
++	buf->vp9.height = dec_params->frame_height_minus_1 + 1;
++	buf->vp9.bit_depth = dec_params->bit_depth;
++}
+\ No newline at end of file
+diff --git a/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9-common.h b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9-common.h
+new file mode 100644
+index 000000000000..056842cf1bba
+--- /dev/null
++++ b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9-common.h
+@@ -0,0 +1,95 @@
++// SPDX-License-Identifier: GPL-2.0
++/*
++ * Rockchip video decoder VP9 common functions
++ *
++ * Copyright (C) 2019 Collabora, Ltd.
++ *	Boris Brezillon <boris.brezillon@collabora.com>
++ * Copyright (C) 2021 Collabora, Ltd.
++ *	Andrzej Pietrasiewicz <andrzej.p@collabora.com>
++ *
++ * Copyright (C) 2016 Rockchip Electronics Co., Ltd.
++ *	Alpha Lin <Alpha.Lin@rock-chips.com>
++ */
++
++#include <media/v4l2-h264.h>
++#include <media/v4l2-mem2mem.h>
++#include <media/v4l2-vp9.h>
++
++#include "rkvdec.h"
++
++struct rkvdec_vp9_run {
++	struct rkvdec_run base;
++	const struct v4l2_ctrl_vp9_frame *decode_params;
++};
++
++struct rkvdec_vp9_intra_mode_probs {
++	u8 y_mode[105];
++	u8 uv_mode[23];
++};
++
++struct rkvdec_vp9_intra_only_frame_probs {
++	u8 coef_intra[4][2][128];
++	struct rkvdec_vp9_intra_mode_probs intra_mode[10];
++};
++
++struct rkvdec_vp9_inter_frame_probs {
++	u8 y_mode[4][9];
++	u8 comp_mode[5];
++	u8 comp_ref[5];
++	u8 single_ref[5][2];
++	u8 inter_mode[7][3];
++	u8 interp_filter[4][2];
++	u8 padding0[11];
++	u8 coef[2][4][2][128];
++	u8 uv_mode_0_2[3][9];
++	u8 padding1[5];
++	u8 uv_mode_3_5[3][9];
++	u8 padding2[5];
++	u8 uv_mode_6_8[3][9];
++	u8 padding3[5];
++	u8 uv_mode_9[9];
++	u8 padding4[7];
++	u8 padding5[16];
++	struct {
++		u8 joint[3];
++		u8 sign[2];
++		u8 classes[2][10];
++		u8 class0_bit[2];
++		u8 bits[2][10];
++		u8 class0_fr[2][2][3];
++		u8 fr[2][3];
++		u8 class0_hp[2];
++		u8 hp[2];
++		u8 padding6[3];
++	} mv;
++};
++
++struct rkvdec_vp9_probs {
++	u8 partition[16][3];
++	u8 pred[3];
++	u8 tree[7];
++	u8 skip[3];
++	u8 tx32[2][3];
++	u8 tx16[2][2];
++	u8 tx8[2][1];
++	u8 is_inter[4];
++	/* 128 bit alignment */
++	u8 padding0[3];
++	union {
++		struct rkvdec_vp9_inter_frame_probs inter;
++		struct rkvdec_vp9_intra_only_frame_probs intra_only;
++	};
++	/* 128 bit alignment */
++	u8 padding1[8];
++};
++
++
++void write_coeff_plane(const u8 coef[6][6][3], u8 *coeff_plane);
++
++struct rkvdec_decoded_buffer *
++get_ref_buf_vp9(struct rkvdec_ctx *ctx, struct vb2_v4l2_buffer *dst, u64 timestamp);
++
++dma_addr_t get_mv_base_addr(struct rkvdec_decoded_buffer *buf);
++
++void update_dec_buf_info(struct rkvdec_decoded_buffer *buf,
++				const struct v4l2_ctrl_vp9_frame *dec_params);
+diff --git a/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c
+index bab2e9c83d06..2b368d7b61e0 100644
+--- a/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c
++++ b/drivers/media/platform/rockchip/rkvdec/rkvdec-vp9.c
+@@ -23,71 +23,12 @@
+ 
+ #include "rkvdec.h"
+ #include "rkvdec-regs.h"
++#include "rkvdec-vp9-common.h"
+ 
+ #define RKVDEC_VP9_PROBE_SIZE		4864
+ #define RKVDEC_VP9_COUNT_SIZE		13232
+ #define RKVDEC_VP9_MAX_SEGMAP_SIZE	73728
+ 
+-struct rkvdec_vp9_intra_mode_probs {
+-	u8 y_mode[105];
+-	u8 uv_mode[23];
+-};
+-
+-struct rkvdec_vp9_intra_only_frame_probs {
+-	u8 coef_intra[4][2][128];
+-	struct rkvdec_vp9_intra_mode_probs intra_mode[10];
+-};
+-
+-struct rkvdec_vp9_inter_frame_probs {
+-	u8 y_mode[4][9];
+-	u8 comp_mode[5];
+-	u8 comp_ref[5];
+-	u8 single_ref[5][2];
+-	u8 inter_mode[7][3];
+-	u8 interp_filter[4][2];
+-	u8 padding0[11];
+-	u8 coef[2][4][2][128];
+-	u8 uv_mode_0_2[3][9];
+-	u8 padding1[5];
+-	u8 uv_mode_3_5[3][9];
+-	u8 padding2[5];
+-	u8 uv_mode_6_8[3][9];
+-	u8 padding3[5];
+-	u8 uv_mode_9[9];
+-	u8 padding4[7];
+-	u8 padding5[16];
+-	struct {
+-		u8 joint[3];
+-		u8 sign[2];
+-		u8 classes[2][10];
+-		u8 class0_bit[2];
+-		u8 bits[2][10];
+-		u8 class0_fr[2][2][3];
+-		u8 fr[2][3];
+-		u8 class0_hp[2];
+-		u8 hp[2];
+-	} mv;
+-};
+-
+-struct rkvdec_vp9_probs {
+-	u8 partition[16][3];
+-	u8 pred[3];
+-	u8 tree[7];
+-	u8 skip[3];
+-	u8 tx32[2][3];
+-	u8 tx16[2][2];
+-	u8 tx8[2][1];
+-	u8 is_inter[4];
+-	/* 128 bit alignment */
+-	u8 padding0[3];
+-	union {
+-		struct rkvdec_vp9_inter_frame_probs inter;
+-		struct rkvdec_vp9_intra_only_frame_probs intra_only;
+-	};
+-	/* 128 bit alignment */
+-	u8 padding1[11];
+-};
+-
+ /* Data structure describing auxiliary buffer format. */
+ struct rkvdec_vp9_priv_tbl {
+ 	struct rkvdec_vp9_probs probs;
+@@ -136,11 +77,6 @@ struct rkvdec_vp9_intra_frame_symbol_counts {
+ 	struct rkvdec_vp9_refs_counts ref_cnt[2][4][2][6][6];
+ };
+ 
+-struct rkvdec_vp9_run {
+-	struct rkvdec_run base;
+-	const struct v4l2_ctrl_vp9_frame *decode_params;
+-};
+-
+ struct rkvdec_vp9_frame_info {
+ 	u32 valid : 1;
+ 	u32 segmapid : 1;
+@@ -166,27 +102,6 @@ struct rkvdec_vp9_ctx {
+ 	struct rkvdec_regs regs;
+ };
+ 
+-static void write_coeff_plane(const u8 coef[6][6][3], u8 *coeff_plane)
+-{
+-	unsigned int idx = 0, byte_count = 0;
+-	int k, m, n;
+-	u8 p;
+-
+-	for (k = 0; k < 6; k++) {
+-		for (m = 0; m < 6; m++) {
+-			for (n = 0; n < 3; n++) {
+-				p = coef[k][m][n];
+-				coeff_plane[idx++] = p;
+-				byte_count++;
+-				if (byte_count == 27) {
+-					idx += 5;
+-					byte_count = 0;
+-				}
+-			}
+-		}
+-	}
+-}
+-
+ static void init_intra_only_probs(struct rkvdec_ctx *ctx,
+ 				  const struct rkvdec_vp9_run *run)
+ {
+@@ -348,36 +263,6 @@ static void init_probs(struct rkvdec_ctx *ctx,
+ 		init_inter_probs(ctx, run);
+ }
+ 
+-static struct rkvdec_decoded_buffer *
+-get_ref_buf_vp9(struct rkvdec_ctx *ctx, struct vb2_v4l2_buffer *dst, u64 timestamp)
+-{
+-	struct v4l2_m2m_ctx *m2m_ctx = ctx->fh.m2m_ctx;
+-	struct vb2_queue *cap_q = &m2m_ctx->cap_q_ctx.q;
+-	struct vb2_buffer *buf;
+-
+-	/*
+-	 * If a ref is unused or invalid, address of current destination
+-	 * buffer is returned.
+-	 */
+-	buf = vb2_find_buffer(cap_q, timestamp);
+-	if (!buf)
+-		buf = &dst->vb2_buf;
+-
+-	return vb2_to_rkvdec_decoded_buf(buf);
+-}
+-
+-static dma_addr_t get_mv_base_addr(struct rkvdec_decoded_buffer *buf)
+-{
+-	unsigned int aligned_pitch, aligned_height, yuv_len;
+-
+-	aligned_height = round_up(buf->vp9.height, 64);
+-	aligned_pitch = round_up(buf->vp9.width * buf->vp9.bit_depth, 512) / 8;
+-	yuv_len = (aligned_height * aligned_pitch * 3) / 2;
+-
+-	return vb2_dma_contig_plane_dma_addr(&buf->base.vb.vb2_buf, 0) +
+-	       yuv_len;
+-}
+-
+ static void config_ref_registers(struct rkvdec_ctx *ctx,
+ 				 const struct rkvdec_vp9_run *run,
+ 				 struct rkvdec_decoded_buffer *ref_buf,
+@@ -446,14 +331,6 @@ static void config_seg_registers(struct rkvdec_ctx *ctx, unsigned int segid)
+ 		(seg->flags & V4L2_VP9_SEGMENTATION_FLAG_ABS_OR_DELTA_UPDATE);
+ }
+ 
+-static void update_dec_buf_info(struct rkvdec_decoded_buffer *buf,
+-				const struct v4l2_ctrl_vp9_frame *dec_params)
+-{
+-	buf->vp9.width = dec_params->frame_width_minus_1 + 1;
+-	buf->vp9.height = dec_params->frame_height_minus_1 + 1;
+-	buf->vp9.bit_depth = dec_params->bit_depth;
+-}
+-
+ static void update_ctx_cur_info(struct rkvdec_vp9_ctx *vp9_ctx,
+ 				struct rkvdec_decoded_buffer *buf,
+ 				const struct v4l2_ctrl_vp9_frame *dec_params)
+-- 
+2.54.0
+

patches/driver/media/README.md

@@ -0,0 +1,69 @@
+# patches/driver/media/
+
+Scope-tagged kernel-agent patches that touch `drivers/media/` — third-party
+video-codec enablement work that hasn't reached linux-media patchwork as
+formal series yet, but is empirically known to work on our test hardware.
+
+## 0001..0003 — Sarma's VP9 enablement on VDPU381 (RK3588 rkvdec)
+
+Three patches from `D.V.A.B. Sarma <vdarbha0473@gmail.com>` adding VP9
+decode support to the VDPU381 variant of rkvdec (the RK3588 generation).
+
+| # | Subject | LOC | What |
+|---|---------|----:|------|
+| 0001 | rkvdec/vp9: rename get_ref_buf to get_ref_buf_vp9 | 10 | rename existing helper to avoid namespace collision with the upcoming HEVC equivalent |
+| 0002 | rkvdec: move vp9 functions to common file | 172 | extract VP9 plumbing into `rkvdec-vp9-common.{c,h}` so VDPU381 can share with the older RK3399 backend |
+| 0003 | rkvdec: add VP9 support for VDPU381 variant | 1303 | the actual VDPU381 VP9 backend — register defs + `rkvdec-vdpu381-vp9.c` + glue |
+
+Combined: ~1500 LOC, 5 new files in `drivers/media/platform/rockchip/rkvdec/`.
+
+### Upstream provenance
+
+- Author maintains the work at https://github.com/dvab-sarma/android_kernel_rk_opi
+  branch `add-rkvdec-vdpu381-vp9-v8`.
+- Collabora's blog post on RK3588/RK3576 video decoder mainline merge cites
+  the work but notes "v1 series needs to be sent for review soon" —
+  i.e. not yet on linux-media patchwork, no upstream timeline.
+- Casanova's VDPU381+VDPU383 H.264/HEVC base (which these patches sit on top
+  of) IS in mainline 7.0 release.
+- Patches do NOT modify any of our scope-tagged board / module / soc /
+  subsystem code paths — purely additive to the upstream rkvdec subdirectory.
+
+### Tested on
+
+- Author: Orange Pi 5 Pro board (RK3588), AOSP 16 + FFMPEG, Profile 0 + Profile 2
+- Our fleet: build verified clean on `ampere` (CoolPi CM5 GenBook, RK3588)
+  2026-05-18 with KERNELRELEASE `7.0.0-rc3-vp9-test+` (base = running
+  `7.0.0-rc3-devices+` config + LOCALVERSION change + these 3 patches +
+  the pre-existing issue14 vb2-resv local mods). Full kernel image
+  + DTB + modules + initramfs land at `/boot/firmware/*-7.0.0-rc3-vp9-test+`
+  and `/lib/modules/7.0.0-rc3-vp9-test+`. New extlinux label `arch_vp9_test`
+  added without touching default `arch_devices`. End-to-end VP9 decode
+  validation requires booting into `arch_vp9_test` (pending operator
+  confirmation, then `v4l2-ctl -d /dev/video1 --list-formats-out` should
+  list `VP9F` alongside `S265` + `S264`).
+
+### Apply order
+
+Strict — 0001 → 0002 → 0003. 0003 depends on the common-file refactor
+from 0002, which depends on the helper rename in 0001.
+
+### Removal criteria
+
+Drop these patches when:
+- Sarma sends a v1 series to linux-media and it lands upstream — adopt
+  the upstream version at the next baseline bump, OR
+- Collabora produces an alternative VP9 enablement on their own
+  hardware-enablement/rockchip-3588 GitLab tree — prefer that lineage
+  (more likely to land cleanly upstream).
+
+### How to use in a kernel-agent build
+
+If `fleet/ampere.yaml` is bumped to include VP9 (currently scope-out per
+the manifest preamble — "Asks #2 (VP9 enablement on RK3588 rkvdec) and
+#3 (AV1 dec integration) from issue #6 are NOT addressed in this
+manifest — tracked separately"), reference these three files in apply
+order under the manifest's scope-tagged patch list.
+
+Cross-references: `marfrit/kernel-agent#12` (the VP9-on-ampere enablement
+issue).

tests/ka-build/run-tests.sh

@@ -0,0 +1,113 @@
+#!/usr/bin/env bash
+# ka-build test suite — dry-run paths only.
+#
+# Phase-1 deliverable per issue #34. The full makepkg path is exercised
+# manually on boltzmann (parity test against the most recent hand-built
+# linux-fresnel-fourier pkg); not in this suite because:
+#   - Needs real ssh to boltzmann + ~30 min build wall time
+#   - Hermetic sandbox would need a mock marfrit-publish-arch on hertz
+# Future-work: add a `--mock-build-host` flag + fixture builder so this
+# can run in CI.
+#
+# What this suite covers:
+#   - Argument parsing + required-host check
+#   - manifest.yaml read + package.name / build_host.primary extraction
+#   - Refuses if manifest.lock missing (ka-promote not run)
+#   - Refuses if PKGBUILD missing
+#   - Refuses on patch drift between kernel-agent and marfrit-packages
+#   - Happy-path dry-run on fresnel (all 6 patches match)
+
+set -euo pipefail
+
+repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
+packages_repo="${PACKAGES_REPO_FOR_TESTS:-${HOME}/src/marfrit-packages}"
+
+pass=0
+fail=0
+results=()
+note() { printf '  %s\n' "$*"; }
+ok()   { results+=("PASS  $1"); pass=$((pass+1)); note "PASS"; }
+ko()   { results+=("FAIL  $1: $2"); fail=$((fail+1)); note "FAIL: $2"; }
+
+# Reset build/ before running so we exercise the "no manifest.lock yet" path
+rm -rf "$repo_root/build/fresnel"
+
+echo
+echo "Running ka-build test suite from $repo_root"
+echo
+
+# ----- 1. requires host arg -----
+echo "::: requires host arg"
+set +e
+out=$("$repo_root/bin/ka-build" 2>&1)
+rc=$?
+set -e
+if [ "$rc" -eq 2 ] && echo "$out" | grep -q "host is required"; then ok "requires host arg"; else ko "requires host arg" "exit=$rc out=$out"; fi
+
+# ----- 2. unknown flag -----
+echo "::: unknown flag rejected"
+set +e
+out=$("$repo_root/bin/ka-build" fresnel --nonsense 2>&1)
+rc=$?
+set -e
+if [ "$rc" -ne 0 ] && echo "$out" | grep -q "unknown flag"; then ok "unknown flag rejected"; else ko "unknown flag rejected" "exit=$rc out=$out"; fi
+
+# ----- 3. refuses if manifest.lock missing -----
+echo "::: refuses if manifest.lock missing (ka-promote not run)"
+set +e
+out=$("$repo_root/bin/ka-build" fresnel --dry-run --packages-repo "$packages_repo" 2>&1)
+rc=$?
+set -e
+if [ "$rc" -eq 2 ] && echo "$out" | grep -q "no manifest.lock"; then ok "refuses no-lock"; else ko "refuses no-lock" "exit=$rc out=$out"; fi
+
+# Now run ka-promote so the rest can proceed
+"$repo_root/bin/ka-promote" fresnel >/dev/null
+
+# ----- 4. refuses if PKGBUILD missing -----
+echo "::: refuses if PKGBUILD missing (--packages-repo wrong)"
+set +e
+out=$("$repo_root/bin/ka-build" fresnel --dry-run --packages-repo /tmp/non-existent-mp 2>&1)
+rc=$?
+set -e
+if [ "$rc" -eq 2 ]; then ok "refuses bad packages-repo"; else ko "refuses bad packages-repo" "exit=$rc out=$out"; fi
+
+# ----- 5. happy-path dry-run -----
+echo "::: happy-path dry-run (fresnel, real packages-repo)"
+if [ ! -f "$packages_repo/arch/linux-fresnel-fourier/PKGBUILD" ]; then
+    note "SKIP: $packages_repo/arch/linux-fresnel-fourier/PKGBUILD not present"
+    results+=("SKIP  happy-path dry-run (PKGBUILD missing locally)")
+else
+    set +e
+    out=$("$repo_root/bin/ka-build" fresnel --dry-run --packages-repo "$packages_repo" 2>&1)
+    rc=$?
+    set -e
+    if [ "$rc" -eq 0 ] && echo "$out" | grep -q "patches OK (6 files)"; then ok "happy-path dry-run"; else ko "happy-path dry-run" "exit=$rc out=$out"; fi
+fi
+
+# ----- 6. patch drift detection -----
+echo "::: patch drift detection (mutate a copied patch, expect exit 3)"
+if [ ! -d "$packages_repo/arch/linux-fresnel-fourier" ]; then
+    note "SKIP: $packages_repo/arch/linux-fresnel-fourier not present"
+    results+=("SKIP  patch drift detection")
+else
+    sandbox=$(mktemp -d -t ka-build-drift.XXXXXX)
+    cp -r "$packages_repo/arch/linux-fresnel-fourier" "$sandbox/linux-fresnel-fourier"
+    mkdir -p "$sandbox/arch"
+    mv "$sandbox/linux-fresnel-fourier" "$sandbox/arch/linux-fresnel-fourier"
+    # Mutate one patch so its sha256 differs from manifest.lock's recorded sha
+    echo "drift" >> "$sandbox/arch/linux-fresnel-fourier/0001-arm64-dts-rk3399-pinebook-pro-add-OC-OPP-tables-1704-2184.patch"
+    set +e
+    out=$("$repo_root/bin/ka-build" fresnel --dry-run --packages-repo "$sandbox" 2>&1)
+    rc=$?
+    set -e
+    rm -rf "$sandbox"
+    if [ "$rc" -eq 3 ] && echo "$out" | grep -q "DRIFT:"; then ok "patch drift detection"; else ko "patch drift detection" "exit=$rc out=$out"; fi
+fi
+
+echo
+echo "===================="
+printf '%s\n' "${results[@]}"
+echo "===================="
+echo "passed: $pass"
+echo "failed: $fail"
+[ "$fail" -eq 0 ] || exit 1

tests/ka-promote/run-tests.sh

@@ -12,8 +12,10 @@ set -euo pipefail
 repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
 fixtures="${repo_root}/tests/ka-promote/fixtures"
 
-# Phase-3 ground truth — recorded 2026-05-18, fresnel cumulative b2sum.
-FRESNEL_EXPECTED_B2SUM=4d9d93c655ea701b587bf1383c794f41b1aeb3bc32bca69ce3488852ec2c1474a2f47585608598b39ac05671490b8df63c5bc7d093f87e1afd5a92f908891b67
+# Phase-3 ground truth — re-recorded 2026-05-19 after issue #31 fix
+# (write_cumulative now strips per-input trailers + emits canonical
+# separators between, but not after, concatenated patches).
+FRESNEL_EXPECTED_B2SUM=9c21751cc48ab57cdf48058cc4309752de169c567bbb898c342ff3e4a5cc79add53e3fd4217c2ae2ae7c16b0f19518cf1791907367e1ea9ef16458e1e90c05e0
 
 pass=0
 fail=0
@@ -110,6 +112,47 @@ echo
 echo "Running ka-promote test suite from $repo_root"
 echo
 
+# ----- unit: strip_trailer + write_cumulative shape (issue #31) -----
+echo "::: strip_trailer + cumulative shape (issue #31)"
+python3 - "$repo_root" <<'PY'
+import importlib.util, pathlib, sys, tempfile, os
+root = pathlib.Path(sys.argv[1])
+from importlib.machinery import SourceFileLoader
+mod = SourceFileLoader("ka_promote", str(root/"bin"/"ka-promote")).load_module()
+
+# strip_trailer accepts both shapes and yields newline-terminated body
+assert mod.strip_trailer(b"...body...\n-- \n2.54.0\n\n") == b"...body...\n"
+assert mod.strip_trailer(b"...body...\n-- \n2.53.0\n\n") == b"...body...\n"
+assert mod.strip_trailer(b"...body...\n-- \n2.20\n\n")   == b"...body...\n"
+assert mod.strip_trailer(b"...body...\n")                  == b"...body...\n"
+assert mod.strip_trailer(b"...body...")                    == b"...body...\n"
+# Multiple trailing blanks after the version still strip
+assert mod.strip_trailer(b"x\n-- \n2.54.0\n\n\n") == b"x\n"
+
+# write_cumulative: 3 inputs (mix of with-/without-trailer), check ordering
+with tempfile.TemporaryDirectory() as d:
+    p1 = os.path.join(d, "a.patch"); open(p1,"wb").write(b"PA\n-- \n2.54.0\n\n")
+    p2 = os.path.join(d, "b.patch"); open(p2,"wb").write(b"PB\n")  # already bare
+    p3 = os.path.join(d, "c.patch"); open(p3,"wb").write(b"PC\n-- \n2.40.1\n\n")
+    out = os.path.join(d, "out.patch")
+    resolved = [{"src": p1}, {"src": p2}, {"src": p3}]
+    mod.write_cumulative(resolved, out)
+    body = open(out,"rb").read()
+    assert body == b"PA\n-- \n2.54.0\n\nPB\n-- \n2.54.0\n\nPC\n", repr(body)
+    # Last patch (PC) must NOT carry an orphan trailer at EOF
+    assert not body.rstrip(b"\n").endswith(b"2.40.1"), \
+        f"last patch's trailer leaked into cumulative: {body[-40:]!r}"
+print("PASS")
+PY
+if [ $? -eq 0 ]; then
+    results+=("PASS  strip_trailer + cumulative shape (issue #31)")
+    pass=$((pass+1))
+else
+    results+=("FAIL  strip_trailer + cumulative shape (issue #31)")
+    fail=$((fail+1))
+fi
+echo
+
 # Use the real fleet/fresnel.yaml — copy into a sandbox so the test is hermetic.
 mkdir -p /tmp/ka-promote-parity-fixture
 cp "$repo_root/fleet/fresnel.yaml" /tmp/ka-promote-parity-fixture/fresnel.yaml