diff --git a/arch/daedalus-v4l2-dkms/PKGBUILD b/arch/daedalus-v4l2-dkms/PKGBUILD
index f343e5fea..db175211a 100644
--- a/arch/daedalus-v4l2-dkms/PKGBUILD
+++ b/arch/daedalus-v4l2-dkms/PKGBUILD
@@ -18,9 +18,9 @@ _module=daedalus_v4l2
 
 # Same pin as arch/daedalus-v4l2 — keep kernel module + daemon
 # bit-versioned together so the chardev wire protocol stays in sync.
-_commit=462aa4b4804972189d2f1b1ab5782f1ca1e8c423
+_commit=f0d41867f60f5bf8dbfcc6cc16404d7d7eb90014
 
-pkgver=0.1.0.r22.462aa4b
+pkgver=0.1.0.r24.f0d4186
 pkgrel=1  # reset for new upstream pin (3dd0eb0 — DAEMON-PPS H.264 SPS/PPS NAL synth)
 pkgdesc="V4L2 stateless decoder shim kernel module (DKMS) — Pi 5 / CM5"
 arch=('any')
diff --git a/arch/daedalus-v4l2/PKGBUILD b/arch/daedalus-v4l2/PKGBUILD
index 8e0f882d6..728594322 100644
--- a/arch/daedalus-v4l2/PKGBUILD
+++ b/arch/daedalus-v4l2/PKGBUILD
@@ -21,11 +21,11 @@ _upstreampkg=daedalus-v4l2
 # ffmpeg -hwaccel vaapi → libva → /dev/video0 → daemon path lands a
 # pixel-correct decoded frame back in ffmpeg.  Promote to a later pin
 # only after a future phase closes cleanly.
-_commit=462aa4b4804972189d2f1b1ab5782f1ca1e8c423
+_commit=f0d41867f60f5bf8dbfcc6cc16404d7d7eb90014
 
 # 0.1.0 (pre-1.0) + commit count + short sha.  Bump the .Y on each
 # Phase 8.x close.  pkgver() recomputes at build time.
-pkgver=0.1.0.r22.462aa4b
+pkgver=0.1.0.r24.f0d4186
 pkgrel=1  # reset for new upstream pin (3dd0eb0 — DAEMON-PPS H.264 SPS/PPS NAL synth)
 pkgdesc="Userspace daemon for the daedalus-v4l2 V4L2 stateless decoder shim (VP9/AV1/H.264 on Pi 5 / CM5)"
 arch=('aarch64')
diff --git a/debian/daedalus-v4l2-dkms/build-deb.sh b/debian/daedalus-v4l2-dkms/build-deb.sh
index 0cd5167aa..e0cea45c0 100755
--- a/debian/daedalus-v4l2-dkms/build-deb.sh
+++ b/debian/daedalus-v4l2-dkms/build-deb.sh
@@ -14,8 +14,8 @@
 # Sibling userspace package: ../daedalus-v4l2/build-deb.sh
 set -euo pipefail
 
-UPSTREAM_COMMIT=462aa4b4804972189d2f1b1ab5782f1ca1e8c423
-PKGVER=0.1.0+r22+g462aa4b
+UPSTREAM_COMMIT=f0d41867f60f5bf8dbfcc6cc16404d7d7eb90014
+PKGVER=0.1.0+r24+gf0d4186
 PKGREL=1  # reset for new upstream pin (3dd0eb0 — DAEMON-PPS H.264 SPS/PPS NAL synth)
 MODULE_NAME=daedalus_v4l2
 
diff --git a/debian/daedalus-v4l2-dkms/debian/changelog b/debian/daedalus-v4l2-dkms/debian/changelog
index 736b39e80..763bde3c2 100644
--- a/debian/daedalus-v4l2-dkms/debian/changelog
+++ b/debian/daedalus-v4l2-dkms/debian/changelog
@@ -1,3 +1,13 @@
+daedalus-v4l2-dkms (0.1.0+r24+gf0d4186-1) bookworm trixie; urgency=medium
+
+  * Bump to f0d4186 — per-ctx vb2 lock fix.  daedalus_queue_init now
+    uses ctx->vb_mutex instead of ctx->dev->m2m_lock for each
+    vb2_queue's lock, unblocking Firefox's multi-process VAAPI
+    clients (they were colliding on the device-wide mutex and one
+    would EBUSY-fail S_FMT while another was mid-streamon).
+
+ -- Markus Fritsche <mfritsche@reauktion.de>  Wed, 20 May 2026 23:00:00 +0000
+
 daedalus-v4l2-dkms (0.1.0+r22+g462aa4b-1) bookworm trixie; urgency=medium
 
   * Bump to 462aa4b — kernel device_run() now calls
diff --git a/debian/daedalus-v4l2/build-deb.sh b/debian/daedalus-v4l2/build-deb.sh
index cb37da284..25560971d 100755
--- a/debian/daedalus-v4l2/build-deb.sh
+++ b/debian/daedalus-v4l2/build-deb.sh
@@ -15,8 +15,8 @@ set -euo pipefail
 # end-to-end via libva (consumer target hit)" — first commit where the
 # full ffmpeg -hwaccel vaapi → libva → /dev/video0 → daemon path lands
 # a pixel-correct decoded frame back in ffmpeg.
-UPSTREAM_COMMIT=462aa4b4804972189d2f1b1ab5782f1ca1e8c423
-PKGVER=0.1.0+r22+g462aa4b
+UPSTREAM_COMMIT=f0d41867f60f5bf8dbfcc6cc16404d7d7eb90014
+PKGVER=0.1.0+r24+gf0d4186
 PKGREL=1  # reset for new upstream pin (3dd0eb0 — DAEMON-PPS H.264 SPS/PPS NAL synth)
 
 HERE=$(dirname "$(readlink -f "$0")")
diff --git a/debian/daedalus-v4l2/debian/changelog b/debian/daedalus-v4l2/debian/changelog
index c8ef631ff..19294756d 100644
--- a/debian/daedalus-v4l2/debian/changelog
+++ b/debian/daedalus-v4l2/debian/changelog
@@ -1,3 +1,22 @@
+daedalus-v4l2 (0.1.0+r24+gf0d4186-1) bookworm trixie; urgency=medium
+
+  * Bump to f0d4186 — kernel per-ctx vb2 lock fix.  daedalus_queue_init
+    was wiring src_vq->lock and dst_vq->lock to ctx->dev->m2m_lock (a
+    device-wide mutex), serialising every vb2 ioctl across all
+    concurrent clients of /dev/video0.  For Firefox (which spawns
+    separate content + RDD + GPU processes that each open the device
+    and run libva probe simultaneously), one libva session's
+    S_FMT(OUTPUT_MPLANE) hit EBUSY while another was mid-streamon —
+    Firefox VAAPI playback fell apart at startup.
+  * Fix gives each open() its own ctx->vb_mutex; vb2 ioctls run
+    independently per client.  Matches cedrus / rkvdec / hantro
+    pattern.
+  * Verified on higgs: Firefox YouTube playback engages VAAPI cleanly,
+    sustained ~230 fps decode at 640x368 through the daedalus daemon,
+    zero EBUSY in stderr or daemon journal.
+
+ -- Markus Fritsche <mfritsche@reauktion.de>  Wed, 20 May 2026 23:00:00 +0000
+
 daedalus-v4l2 (0.1.0+r22+g462aa4b-1) bookworm trixie; urgency=medium
 
   * Bump to 462aa4b — kernel-side fix for control-binding gap that