feat(windows): pf-vdisplay IDD-push — HDR + pipelined zero-copy capture

HDR (display-driven, matching the WGC path):
- CTA-861.3 HDR EDID (BT.2020 primaries + HDR Static Metadata block) so Windows
  offers "Use HDR" on the virtual display. The host FOLLOWS the display's live
  advanced-color state, recreating the shared ring at the matching format
  (FP16 in HDR / BGRA in SDR) on a toggle — no freeze.
- Always emit Main10/BT.2020-PQ Rgb10a2 while the display is HDR; the client
  auto-detects PQ from the HEVC VUI (clients under-report VIDEO_CAP_10BIT).
  Generic HDR10 mastering SEI on every IDR.
- Generation-tagged `latest` (gen<<40|seq<<8|slot) + driver `is_stale` re-attach
  kill the toggle-time garbage frame and any stale-ring read.

Perf:
- Pipeline the encode loop (Capturer::pipeline_depth; IDD-push = 2): submit N+1
  before polling N so the convert/copy on the 3D engine overlaps the NVENC encode
  of N on the ASIC. PUNKTFUNK_IDD_DEPTH overrides (1 = synchronous).
- Rotating host output ring (OUT_RING) so the in-flight encode and the next
  convert never touch the same texture.
- HDR converts directly from the keyed-mutex slot's SRV into the output ring
  (drops the redundant slot->fp16 scratch copy); SDR copies the BGRA slot in.
  The slot mutex is held only across the convert/copy, not the encode.
  RING_LEN 3->6 for publish headroom.
- Capture-health diagnostic: new_fps vs repeat_fps under PUNKTFUNK_PERF (a low
  new_fps at a high send rate means the source isn't compositing, not an encode
  stall).

Validated live on the RTX box: 5120x1440@240 HDR streams; driver composes
~180 new fps, encode 240 fps @ ~4.3 ms p50.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

packaging/windows/vdisplay-driver/pf-vdisplay/Cargo.toml

@@ -21,6 +21,7 @@ features = [
     "Win32_Security",
     "Win32_System_SystemServices",
     "Win32_System_Threading",
+    "Win32_System_Memory",
     "Win32_System_Diagnostics_Debug",
     "Win32_Graphics_Direct3D",
     "Win32_Graphics_Direct3D11",

packaging/windows/vdisplay-driver/pf-vdisplay/src/callbacks.rs

@@ -11,10 +11,17 @@ use wdf_umdf_sys::{
     DISPLAYCONFIG_TARGET_MODE, DISPLAYCONFIG_VIDEO_SIGNAL_INFO, IDARG_IN_ADAPTER_INIT_FINISHED,
     IDARG_IN_COMMITMODES, IDARG_IN_GETDEFAULTDESCRIPTIONMODES, IDARG_IN_PARSEMONITORDESCRIPTION,
     IDARG_IN_QUERYTARGETMODES, IDARG_IN_SETSWAPCHAIN, IDARG_OUT_GETDEFAULTDESCRIPTIONMODES,
-    IDARG_OUT_PARSEMONITORDESCRIPTION, IDARG_OUT_QUERYTARGETMODES, IDDCX_ADAPTER__,
+    IDARG_OUT_PARSEMONITORDESCRIPTION, IDARG_OUT_QUERYTARGETMODES, IDDCX_ADAPTER__, IDDCX_PATH,
     IDDCX_MONITOR_MODE, IDDCX_MONITOR_MODE_ORIGIN, IDDCX_MONITOR__, IDDCX_TARGET_MODE, NTSTATUS,
     WDFDEVICE, WDF_POWER_DEVICE_STATE,
 };
+// IddCx 1.10 *2 DDIs (HDR-capable). For B1 we advertise SDR (8 bpc) so behaviour is unchanged; B2
+// flips the bit depth + adapter flag to enable HDR.
+use wdf_umdf_sys::{
+    IDARG_IN_COMMITMODES2, IDARG_IN_PARSEMONITORDESCRIPTION2, IDARG_IN_QUERYTARGETMODES2,
+    IDARG_IN_QUERYTARGET_INFO, IDARG_OUT_QUERYTARGET_INFO, IDDCX_BITS_PER_COMPONENT, IDDCX_MONITOR_MODE2,
+    IDDCX_PATH2, IDDCX_TARGET_CAPS, IDDCX_TARGET_MODE2, IDDCX_WIRE_BITS_PER_COMPONENT,
+};
 
 use crate::{
     context::{DeviceContext, MonitorContext},
@@ -179,6 +186,7 @@ pub extern "C-unwind" fn monitor_get_default_modes(
     _p_in_args: *const IDARG_IN_GETDEFAULTDESCRIPTIONMODES,
     _p_out_args: *mut IDARG_OUT_GETDEFAULTDESCRIPTIONMODES,
 ) -> NTSTATUS {
+    info!("GET_DEFAULT_MODES called (we return NOT_IMPLEMENTED — only valid for a monitor with NO EDID)");
     NTSTATUS::STATUS_NOT_IMPLEMENTED
 }
 
@@ -287,9 +295,20 @@ pub extern "C-unwind" fn monitor_query_modes(
 
 pub extern "C-unwind" fn adapter_commit_modes(
     _adapter_object: *mut IDDCX_ADAPTER__,
-    _p_in_args: *const IDARG_IN_COMMITMODES,
+    p_in_args: *const IDARG_IN_COMMITMODES,
 ) -> NTSTATUS {
-    // The swap-chain is managed by IddCx; there is nothing device-specific to reconfigure on a commit.
+    // DIAGNOSTIC: does the OS commit an ACTIVE path for our monitor? IDDCX_PATH_FLAGS_ACTIVE = 2. If
+    // no active path is ever committed, the OS never calls ASSIGN_SWAPCHAIN (the bug we're chasing).
+    let in_args = unsafe { &*p_in_args };
+    info!("COMMIT_MODES: path_count={}", in_args.PathCount);
+    for i in 0..in_args.PathCount {
+        let path: &IDDCX_PATH = unsafe { &*in_args.pPaths.add(i as usize) };
+        let active = (path.Flags.0 & 2) != 0;
+        info!(
+            "  path[{i}] monitor={:p} flags=0x{:x} active={active}",
+            path.MonitorObject, path.Flags.0
+        );
+    }
     NTSTATUS::STATUS_SUCCESS
 }
 
@@ -320,3 +339,194 @@ pub extern "C-unwind" fn unassign_swap_chain(monitor_object: *mut IDDCX_MONITOR_
         .into()
     }
 }
+
+// ===== IddCx 1.10 *2 DDIs (HDR-capable path) ============================================
+// These mirror the 1.x callbacks above but advertise per-mode wire bit-depth. B1 reports SDR (8 bpc);
+// B2 bumps `wire_bits()` to add 10 bpc + sets CAN_PROCESS_FP16 to actually enable HDR.
+
+/// Wire bit-depth advertised per mode. B2: advertise BOTH 8 and 10 bpc RGB so the OS offers HDR10
+/// modes (the bitfield: 8 = 0x2, 10 = 0x4).
+fn wire_bits() -> IDDCX_WIRE_BITS_PER_COMPONENT {
+    let rgb = IDDCX_BITS_PER_COMPONENT(
+        IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_8.0
+            | IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_10.0,
+    );
+    IDDCX_WIRE_BITS_PER_COMPONENT {
+        Rgb: rgb,
+        YCbCr444: IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_NONE,
+        YCbCr422: IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_NONE,
+        YCbCr420: IDDCX_BITS_PER_COMPONENT::IDDCX_BITS_PER_COMPONENT_NONE,
+    }
+}
+
+/// 1.10 variant of [`parse_monitor_description`] — writes `IDDCX_MONITOR_MODE2` (adds bit-depth).
+pub extern "C-unwind" fn parse_monitor_description2(
+    p_in_args: *const IDARG_IN_PARSEMONITORDESCRIPTION2,
+    p_out_args: *mut IDARG_OUT_PARSEMONITORDESCRIPTION,
+) -> NTSTATUS {
+    let in_args = unsafe { &*p_in_args };
+    let out_args = unsafe { &mut *p_out_args };
+
+    let Ok(monitors) = MONITOR_MODES.lock() else {
+        error!("MONITOR_MODES mutex poisoned");
+        return NTSTATUS::STATUS_DRIVER_INTERNAL_ERROR;
+    };
+
+    let edid = unsafe {
+        std::slice::from_raw_parts(
+            in_args.MonitorDescription.pData as *const u8,
+            in_args.MonitorDescription.DataSize as usize,
+        )
+    };
+    let Ok(monitor_index) = Edid::get_serial(edid) else {
+        error!("bad edid ({} bytes)", edid.len());
+        return NTSTATUS::STATUS_INVALID_VIEW_SIZE;
+    };
+    let Some(monitor) = monitors.iter().find(|&m| m.data.id == monitor_index) else {
+        error!("Failed to find monitor id {monitor_index}");
+        return NTSTATUS::STATUS_DRIVER_INTERNAL_ERROR;
+    };
+
+    let number_of_modes: u32 = monitor
+        .data
+        .modes
+        .iter()
+        .map(|m| u32::try_from(m.refresh_rates.len()).expect("Cannot use > u32::MAX refresh rates"))
+        .sum();
+
+    out_args.MonitorModeBufferOutputCount = number_of_modes;
+    if in_args.MonitorModeBufferInputCount < number_of_modes {
+        return if in_args.MonitorModeBufferInputCount > 0 {
+            NTSTATUS::STATUS_BUFFER_TOO_SMALL
+        } else {
+            NTSTATUS::STATUS_SUCCESS
+        };
+    }
+
+    let monitor_modes = unsafe {
+        std::slice::from_raw_parts_mut(
+            in_args.pMonitorModes.cast::<MaybeUninit<IDDCX_MONITOR_MODE2>>(),
+            number_of_modes as usize,
+        )
+    };
+    for (mode, out_mode) in monitor.data.modes.flatten().zip(monitor_modes.iter_mut()) {
+        out_mode.write(IDDCX_MONITOR_MODE2 {
+            #[allow(clippy::cast_possible_truncation)]
+            Size: mem::size_of::<IDDCX_MONITOR_MODE2>() as u32,
+            Origin: IDDCX_MONITOR_MODE_ORIGIN::IDDCX_MONITOR_MODE_ORIGIN_MONITORDESCRIPTOR,
+            MonitorVideoSignalInfo: display_info(mode.width, mode.height, mode.refresh_rate),
+            BitsPerComponent: wire_bits(),
+        });
+    }
+    out_args.PreferredMonitorModeIdx = 0;
+    NTSTATUS::STATUS_SUCCESS
+}
+
+fn target_mode2(width: u32, height: u32, refresh_rate: u32) -> IDDCX_TARGET_MODE2 {
+    let m1 = target_mode(width, height, refresh_rate);
+    IDDCX_TARGET_MODE2 {
+        #[allow(clippy::cast_possible_truncation)]
+        Size: mem::size_of::<IDDCX_TARGET_MODE2>() as u32,
+        TargetVideoSignalInfo: m1.TargetVideoSignalInfo,
+        BitsPerComponent: wire_bits(),
+        ..Default::default()
+    }
+}
+
+/// 1.10 variant of [`monitor_query_modes`] — writes `IDDCX_TARGET_MODE2`.
+pub extern "C-unwind" fn monitor_query_modes2(
+    monitor_object: *mut IDDCX_MONITOR__,
+    p_in_args: *const IDARG_IN_QUERYTARGETMODES2,
+    p_out_args: *mut IDARG_OUT_QUERYTARGETMODES,
+) -> NTSTATUS {
+    let Ok(monitors) = MONITOR_MODES.lock() else {
+        error!("MONITOR_MODES mutex poisoned");
+        return NTSTATUS::STATUS_DRIVER_INTERNAL_ERROR;
+    };
+    let Some(monitor) = monitors
+        .iter()
+        .find(|&m| m.object.is_some_and(|p| p.as_ptr() == monitor_object))
+    else {
+        error!("Failed to find monitor object in cache for {monitor_object:?}");
+        return NTSTATUS::STATUS_DRIVER_INTERNAL_ERROR;
+    };
+
+    let number_of_modes = monitor
+        .data
+        .modes
+        .iter()
+        .map(|m| u32::try_from(m.refresh_rates.len()).expect("Cannot use > u32::MAX modes"))
+        .sum();
+
+    let out_args = unsafe { &mut *p_out_args };
+    out_args.TargetModeBufferOutputCount = number_of_modes;
+
+    let in_args = unsafe { &*p_in_args };
+    if in_args.TargetModeBufferInputCount >= number_of_modes {
+        let out_target_modes = unsafe {
+            std::slice::from_raw_parts_mut(
+                in_args.pTargetModes.cast::<MaybeUninit<IDDCX_TARGET_MODE2>>(),
+                number_of_modes as usize,
+            )
+        };
+        for (mode, out_target) in monitor.data.modes.flatten().zip(out_target_modes.iter_mut()) {
+            out_target.write(target_mode2(mode.width, mode.height, mode.refresh_rate));
+        }
+    }
+    NTSTATUS::STATUS_SUCCESS
+}
+
+/// 1.10 variant of [`adapter_commit_modes`] — `IDDCX_PATH2` carries the committed wire format.
+pub extern "C-unwind" fn adapter_commit_modes2(
+    _adapter_object: *mut IDDCX_ADAPTER__,
+    p_in_args: *const IDARG_IN_COMMITMODES2,
+) -> NTSTATUS {
+    let in_args = unsafe { &*p_in_args };
+    info!("COMMIT_MODES2: path_count={}", in_args.PathCount);
+    for i in 0..in_args.PathCount {
+        let path: &IDDCX_PATH2 = unsafe { &*in_args.pPaths.add(i as usize) };
+        let active = (path.Flags.0 & 2) != 0;
+        info!(
+            "  path2[{i}] monitor={:p} flags=0x{:x} active={active} colorspace={} rgb_bpc=0x{:x}",
+            path.MonitorObject,
+            path.Flags.0,
+            path.WireFormatInfo.ColorSpace.0,
+            path.WireFormatInfo.BitsPerComponent.Rgb.0
+        );
+    }
+    NTSTATUS::STATUS_SUCCESS
+}
+
+/// 1.10 NEW: per-target capabilities. B2 reports `HIGH_COLOR_SPACE` so the OS enables HDR10 (transfer
+/// curve + wide gamut) on this target.
+pub extern "C-unwind" fn query_target_info(
+    _adapter_object: *mut IDDCX_ADAPTER__,
+    _p_in_args: *mut IDARG_IN_QUERYTARGET_INFO,
+    p_out_args: *mut IDARG_OUT_QUERYTARGET_INFO,
+) -> NTSTATUS {
+    let out_args = unsafe { &mut *p_out_args };
+    out_args.TargetCaps = IDDCX_TARGET_CAPS::IDDCX_TARGET_CAPS_HIGH_COLOR_SPACE;
+    out_args.DitheringSupport = IDDCX_WIRE_BITS_PER_COMPONENT::default();
+    NTSTATUS::STATUS_SUCCESS
+}
+
+/// 1.10 NEW (HDR): the OS hands us the default HDR10 static metadata for the monitor. B2 accepts it
+/// (the host/client own the final HDR metadata for the stream); B3 will forward it to the host for the
+/// HEVC mastering-display SEI. Stub keeps the OS's HDR setup happy.
+pub extern "C-unwind" fn set_default_hdr_metadata(
+    _monitor_object: *mut IDDCX_MONITOR__,
+    _p_in_args: *const wdf_umdf_sys::IDARG_IN_MONITOR_SET_DEFAULT_HDR_METADATA,
+) -> NTSTATUS {
+    NTSTATUS::STATUS_SUCCESS
+}
+
+/// 1.10 HDR: the OS hands us the gamma ramp (a 3x4 colour-space matrix in HDR mode). We do NOT apply it
+/// server-side — the host streams the scRGB FP16 and the CLIENT's display applies its own transform —
+/// so we accept it. Wiring this is OBLIGATED once CAN_PROCESS_FP16 is set; without it the OS rejects
+/// the adapter at init (`IddCxAdapterInitAsync` → "Failed to get adapter").
+pub extern "C-unwind" fn set_gamma_ramp(
+    _monitor_object: *mut IDDCX_MONITOR__,
+    _p_in_args: *const wdf_umdf_sys::IDARG_IN_SET_GAMMARAMP,
+) -> NTSTATUS {
+    NTSTATUS::STATUS_SUCCESS
+}

packaging/windows/vdisplay-driver/pf-vdisplay/src/context.rs

@@ -2,6 +2,7 @@ use std::{
     mem::{self, size_of},
     num::{ParseIntError, TryFromIntError},
     ptr::{addr_of_mut, NonNull},
+    sync::{Arc, Mutex},
 };
 
 use anyhow::anyhow;
@@ -13,7 +14,7 @@ use wdf_umdf::{
 use wdf_umdf_sys::{
     DISPLAYCONFIG_VIDEO_OUTPUT_TECHNOLOGY, HANDLE, IDARG_IN_ADAPTER_INIT, IDARG_IN_MONITORCREATE,
     IDARG_IN_SETUP_HWCURSOR, IDARG_OUT_ADAPTER_INIT, IDARG_OUT_MONITORARRIVAL,
-    IDARG_OUT_MONITORCREATE, IDDCX_ADAPTER, IDDCX_ADAPTER_CAPS, IDDCX_CURSOR_CAPS,
+    IDARG_OUT_MONITORCREATE, IDDCX_ADAPTER, IDDCX_ADAPTER_CAPS, IDDCX_ADAPTER_FLAGS, IDDCX_CURSOR_CAPS,
     IDDCX_ENDPOINT_DIAGNOSTIC_INFO, IDDCX_ENDPOINT_VERSION, IDDCX_FEATURE_IMPLEMENTATION,
     IDDCX_MONITOR, IDDCX_MONITOR_DESCRIPTION, IDDCX_MONITOR_DESCRIPTION_TYPE, IDDCX_MONITOR_INFO,
     IDDCX_SWAPCHAIN, IDDCX_TRANSMISSION_TYPE, IDDCX_XOR_CURSOR_SUPPORT, LUID, NTSTATUS, WDFDEVICE,
@@ -34,6 +35,37 @@ use crate::{
 // Maximum amount of monitors that can be connected
 pub const MAX_MONITORS: u8 = 16;
 
+/// ONE shared D3D render device, reused across every swap-chain assignment (keyed by render LUID).
+/// Creating a fresh `Direct3DDevice` per assign — and the swap-chain flap fires several assigns per
+/// session — spawned a new NVIDIA UMD worker-thread set each time that was NEVER reclaimed on release
+/// (proven on the RTX box: ~70 `nvwgf2umx` threads + ~50 MB VRAM leaked per reconnect, permanently,
+/// even though our `Direct3DDevice` refcount dropped to 0). Pooling one device keeps a single, stable
+/// thread set: the processors borrow an `Arc`, so the device outlives them and is never re-created.
+static DEVICE_POOL: Mutex<Option<(i64, Arc<Direct3DDevice>)>> = Mutex::new(None);
+
+/// Get-or-create the pooled D3D device for `luid`. Re-creates only if the render adapter changes
+/// (e.g. a GPU hot-swap), which drops the old `Arc` once its last processor releases it.
+fn pooled_device(luid: windows::Win32::Foundation::LUID) -> Option<Arc<Direct3DDevice>> {
+    let key = (i64::from(luid.HighPart) << 32) | i64::from(luid.LowPart as u32);
+    let mut pool = DEVICE_POOL.lock().ok()?;
+    if let Some((k, dev)) = pool.as_ref() {
+        if *k == key {
+            return Some(dev.clone());
+        }
+    }
+    match Direct3DDevice::init(luid) {
+        Ok(d) => {
+            let a = Arc::new(d);
+            *pool = Some((key, a.clone()));
+            Some(a)
+        }
+        Err(e) => {
+            error!("pooled Direct3DDevice::init failed: {e:?}");
+            None
+        }
+    }
+}
+
 pub struct DeviceContext {
     device: WDFDEVICE,
     adapter: Option<IDDCX_ADAPTER>,
@@ -48,6 +80,11 @@ unsafe impl Sync for DeviceContext {}
 pub struct MonitorContext {
     device: IDDCX_MONITOR,
     swap_chain_processor: Option<SwapChainProcessor>,
+    /// OS target id (from IddCxMonitorArrival), stamped on this context at creation. assign_swap_chain
+    /// uses THIS instead of a MONITOR_MODES pointer lookup — the lookup returns 0 for a recreated
+    /// (session-2+) monitor, which broke the shared-ring naming and cascaded into SetDevice
+    /// E_INVALIDARG + an access violation (the fix-teardown crash).
+    target_id: u32,
 }
 
 // SAFETY: Raw ptr is managed by external library
@@ -98,6 +135,10 @@ impl DeviceContext {
             #[allow(clippy::cast_possible_truncation)]
             Size: size_of::<IDDCX_ADAPTER_CAPS>() as u32,
 
+            // B2 HDR: declare we can process FP16 (scRGB) desktop surfaces — enables HDR10 / SDR WCG.
+            // This OBLIGATES the *2 mode DDIs (done) + ReleaseAndAcquireBuffer2 (done in run_core).
+            Flags: IDDCX_ADAPTER_FLAGS::IDDCX_ADAPTER_FLAGS_CAN_PROCESS_FP16,
+
             MaxMonitorsSupported: u32::from(MAX_MONITORS),
 
             EndPointDiagnostics: IDDCX_ENDPOINT_DIAGNOSTIC_INFO {
@@ -231,6 +272,14 @@ impl DeviceContext {
             }
         }
 
+        // Stamp the OS target id onto the monitor's CONTEXT so assign_swap_chain reads it directly
+        // (no MONITOR_MODES pointer lookup, which returns 0 for a recreated monitor).
+        unsafe {
+            let _ = MonitorContext::get_mut(monitor_create_out.MonitorObject.cast(), |ctx| {
+                ctx.target_id = arrival_out.OsTargetId;
+            });
+        }
+
         Ok(())
     }
 }
@@ -240,6 +289,7 @@ impl MonitorContext {
         Self {
             device,
             swap_chain_processor: None,
+            target_id: 0,
         }
     }
 
@@ -265,20 +315,37 @@ impl MonitorContext {
             render_adapter.HighPart, render_adapter.LowPart
         );
 
-        let device = Direct3DDevice::init(luid);
+        // The OS target id keys the per-monitor shared frame-push objects (header/event/textures) the
+        // host opens. Read it from THIS context (stamped at creation after IddCxMonitorArrival) — the
+        // old MONITOR_MODES pointer lookup returned 0 for a recreated (session-2+) monitor, which broke
+        // the ring naming and cascaded into SetDevice E_INVALIDARG + an access violation.
+        let target_id = self.target_id;
 
-        if let Ok(device) = device {
+        let device = pooled_device(luid);
+
+        if let Some(device) = device {
             let mut processor = SwapChainProcessor::new();
 
-            processor.run(swap_chain, device, new_frame_event);
+            processor.run(
+                swap_chain,
+                device,
+                new_frame_event,
+                target_id,
+                render_adapter.LowPart,
+                render_adapter.HighPart,
+            );
 
             self.swap_chain_processor = Some(processor);
 
-            self.setup_hw_cursor();
+            // Cursor is BAKED into the captured video: for IDD-push we deliberately do NOT advertise a
+            // hardware cursor, so DWM software-composites the mouse cursor into the swapchain surface we
+            // capture — the client then sees the cursor in the stream. (A future separate-plane cursor
+            // would re-enable setup_hw_cursor + IddCxMonitorQueryHardwareCursor.) Not advertising one
+            // also stops leaking a CreateEventA handle per assign.
         } else {
-            // It's important to delete the swap-chain if D3D initialization fails, so that the OS knows to generate a new
-            // swap-chain and try again.
-            error!("Direct3DDevice::init FAILED on render LUID: {device:?} — deleting swap chain for OS retry");
+            // It's important to delete the swap-chain if D3D init fails, so the OS generates a fresh
+            // swap-chain and retries.
+            error!("pooled Direct3DDevice unavailable for render LUID — deleting swap chain for OS retry");
 
             unsafe {
                 let _ = WdfObjectDelete(swap_chain.cast());
@@ -287,9 +354,15 @@ impl MonitorContext {
     }
 
     pub fn unassign_swap_chain(&mut self) {
-        self.swap_chain_processor.take();
+        let had = self.swap_chain_processor.take().is_some();
+        error!("unassign_swap_chain (target={}) — dropped live processor: {had}", self.target_id);
     }
 
+    /// Advertise a HARDWARE cursor. NOT called for IDD-push — we bake the cursor into the video
+    /// instead (see `assign_swap_chain`). Kept for a future separate-plane cursor (which would pair it
+    /// with `IddCxMonitorQueryHardwareCursor`). Leaks a `CreateEventA` handle per call, so only wire it
+    /// back up alongside a real cursor-plane consumer.
+    #[allow(dead_code)]
     pub fn setup_hw_cursor(&mut self) {
         let mouse_event = unsafe { CreateEventA(None, false, false, s!("vdd_mouse_event")) };
         let Ok(mouse_event) = mouse_event else {

packaging/windows/vdisplay-driver/pf-vdisplay/src/control.rs

@@ -6,8 +6,9 @@
 use std::ffi::c_void;
 use std::mem::size_of;
 use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::Mutex;
 use std::thread;
-use std::time::Duration;
+use std::time::{Duration, Instant};
 
 use log::{error, info};
 use wdf_umdf::{
@@ -16,7 +17,7 @@ use wdf_umdf::{
 };
 use wdf_umdf_sys::{IDARG_IN_ADAPTERSETRENDERADAPTER, LUID, NTSTATUS, WDFDEVICE, WDFREQUEST};
 
-use crate::context::DeviceContext;
+use crate::context::{DeviceContext, MonitorContext};
 use crate::monitor::{
     default_modes, Mode, MonitorData, MonitorObject, ADAPTER, MONITOR_MODES, NEXT_ID,
     PREFERRED_RENDER_ADAPTER, PROTOCOL_VERSION, WATCHDOG_COUNTDOWN, WATCHDOG_TIMEOUT,
@@ -37,6 +38,16 @@ const IOCTL_CLEAR_ALL: u32 = ctl(0x804);
 const IOCTL_PING: u32 = ctl(0x888);
 const IOCTL_GET_VERSION: u32 = ctl(0x8FF);
 
+/// Serializes monitor lifecycle ops — ADD / REMOVE / watchdog-teardown — against each other. Without
+/// it, a watchdog expiry can drain an entry out from under an in-flight `do_add` (which releases the
+/// `MONITOR_MODES` lock before the slow `create_monitor`), leaving `do_add` to return
+/// `STATUS_UNSUCCESSFUL` → the host sees `ERROR_GEN_FAILURE`. This was the reconnect-churn fault.
+static MONITOR_OP_LOCK: Mutex<()> = Mutex::new(());
+/// A monitor created less than this ago is still in its host-side setup window (CCD commit + GDI-name
+/// resolve + topology settle, ~5 s) and is never reaped by the watchdog — only by an explicit
+/// CLEAR_ALL. Protects a freshly-born monitor from a transient PING gap during reconnect churn.
+const MONITOR_GRACE: Duration = Duration::from_secs(6);
+
 #[repr(C)]
 struct AddParams {
     width: u32,
@@ -117,7 +128,7 @@ pub extern "C-unwind" fn device_io_control(
             IOCTL_GET_WATCHDOG => do_get_watchdog(request, output_len, &mut bytes),
             IOCTL_PING => NTSTATUS::STATUS_SUCCESS,
             IOCTL_CLEAR_ALL => {
-                disconnect_all_monitors();
+                disconnect_all_monitors(true);
                 NTSTATUS::STATUS_SUCCESS
             }
             IOCTL_GET_VERSION => do_get_version(request, output_len, &mut bytes),
@@ -136,6 +147,11 @@ unsafe fn do_add(
     output_len: usize,
     bytes: &mut usize,
 ) -> NTSTATUS {
+    // Serialize the whole ADD (push entry → create_monitor → verify) against the watchdog teardown +
+    // REMOVE, so an expiry can never drain this entry mid-flight. `create_monitor` is fast (the slow
+    // CCD/GDI work is host-side, after this returns), and PING/GET_WATCHDOG don't take this lock, so
+    // the host keeps the watchdog reset while we hold it.
+    let _op = MONITOR_OP_LOCK.lock().unwrap();
     if input_len < size_of::<AddParams>() || output_len < size_of::<AddOut>() {
         return NTSTATUS::STATUS_BUFFER_TOO_SMALL;
     }
@@ -182,6 +198,7 @@ unsafe fn do_add(
         target_id: 0,
         adapter_luid_low: 0,
         adapter_luid_high: 0,
+        created_at: Instant::now(),
     });
 
     // Create the IddCx monitor via the device context (captures target id + LUID into the entry).
@@ -226,18 +243,37 @@ unsafe fn do_remove(request: WDFREQUEST, input_len: usize) -> NTSTATUS {
     let params = unsafe { &*pin.cast::<RemoveParams>() };
     let guid = guid_key(&params.guid);
 
-    let mut lock = MONITOR_MODES.lock().unwrap();
-    if let Some(pos) = lock.iter().position(|m| m.guid == guid) {
-        let mon = lock.remove(pos);
-        if let Some(obj) = mon.object {
-            if let Err(e) = unsafe { IddCxMonitorDeparture(obj.as_ptr()) } {
-                error!("REMOVE: departure failed: {e:?}");
-            }
+    // Serialize against ADD + watchdog teardown (lock order: OP_LOCK → MONITOR_MODES).
+    let _op = MONITOR_OP_LOCK.lock().unwrap();
+    let mon = {
+        let mut lock = MONITOR_MODES.lock().unwrap();
+        match lock.iter().position(|m| m.guid == guid) {
+            Some(pos) => lock.remove(pos),
+            None => return NTSTATUS::STATUS_NOT_FOUND,
         }
-        info!("REMOVE target_id={}", mon.target_id);
-        NTSTATUS::STATUS_SUCCESS
-    } else {
-        NTSTATUS::STATUS_NOT_FOUND
+        // MONITOR_MODES released here — the processor-join + departure below must not hold it.
+    };
+    if let Some(obj) = mon.object {
+        free_swap_chain_processor(obj.as_ptr());
+        if let Err(e) = unsafe { IddCxMonitorDeparture(obj.as_ptr()) } {
+            error!("REMOVE: departure failed: {e:?}");
+        }
+    }
+    info!("REMOVE target_id={}", mon.target_id);
+    NTSTATUS::STATUS_SUCCESS
+}
+
+/// Drop a monitor's live swap-chain processor BEFORE departure. The WDF context is an
+/// `Arc<RwLock<MonitorContext>>` that WDF frees WITHOUT running Rust `Drop` (no `EvtCleanupCallback`
+/// is wired), and the OS does not reliably call UNASSIGN on a host-initiated departure — so the
+/// streaming `Direct3DDevice` (its ~dozens of D3D worker threads + tens of MB of VRAM) was orphaned
+/// once per session, the dominant reconnect-churn leak. `get_mut` takes the context `RwLock`, so this
+/// is safe against a concurrent OS unassign callback (whichever runs second sees `None`).
+fn free_swap_chain_processor(monitor: *mut wdf_umdf_sys::IDDCX_MONITOR__) {
+    // SAFETY: `monitor` is a live IddCx monitor object whose context was init'd at creation.
+    let r = unsafe { MonitorContext::get_mut(monitor.cast(), |ctx| ctx.unassign_swap_chain()) };
+    if let Err(e) = r {
+        error!("free_swap_chain_processor: get_mut FAILED: {e:?}");
     }
 }
 
@@ -295,22 +331,46 @@ unsafe fn do_get_version(request: WDFREQUEST, output_len: usize, bytes: &mut usi
     NTSTATUS::STATUS_SUCCESS
 }
 
-/// Tear down every monitor (watchdog expiry — the host is gone). Mirrors SudoVDA's DisconnectAllMonitors.
-fn disconnect_all_monitors() {
-    let mut lock = MONITOR_MODES.lock().unwrap();
-    if lock.is_empty() {
-        return;
-    }
-    for mon in lock.drain(..) {
+/// Tear down monitors. `force` (CLEAR_ALL) reaps EVERYTHING — orphans from a crashed previous host;
+/// the watchdog passes `false`, which spares any monitor still inside its creation grace
+/// (`MONITOR_GRACE`) so a freshly-born monitor is never reaped mid-setup. Caller MUST hold
+/// `MONITOR_OP_LOCK` (lock order: OP_LOCK → MONITOR_MODES). Mirrors SudoVDA's DisconnectAllMonitors.
+fn disconnect_all_monitors_locked(force: bool) {
+    // Drain under the lock (fast); free processors + depart OUTSIDE it (the processor-join blocks).
+    let to_depart: Vec<MonitorObject> = {
+        let mut lock = MONITOR_MODES.lock().unwrap();
+        if lock.is_empty() {
+            return;
+        }
+        let mut keep: Vec<MonitorObject> = Vec::new();
+        let mut depart: Vec<MonitorObject> = Vec::new();
+        for mon in lock.drain(..) {
+            if !force && mon.created_at.elapsed() < MONITOR_GRACE {
+                keep.push(mon); // still in its host-side setup window — leave it alone
+            } else {
+                depart.push(mon);
+            }
+        }
+        *lock = keep;
+        depart
+    };
+    for mon in to_depart {
         if let Some(obj) = mon.object {
+            free_swap_chain_processor(obj.as_ptr());
             // SAFETY: `obj` is a live IddCx monitor object.
             if let Err(e) = unsafe { IddCxMonitorDeparture(obj.as_ptr()) } {
-                error!("watchdog: monitor departure failed: {e:?}");
+                error!("teardown: monitor departure failed: {e:?}");
             }
         }
     }
 }
 
+/// Public entry: takes `MONITOR_OP_LOCK`, then tears down. Used by CLEAR_ALL (`force = true`).
+fn disconnect_all_monitors(force: bool) {
+    let _op = MONITOR_OP_LOCK.lock().unwrap();
+    disconnect_all_monitors_locked(force);
+}
+
 /// Start the watchdog thread (once). The host reads the timeout via GET_WATCHDOG and PINGs every
 /// timeout/3; if it stops, the countdown reaches 0 and every monitor is torn down — so a crashed/gone
 /// host never leaves a phantom display. Mirrors SudoVDA's RunWatchdog.
@@ -340,8 +400,14 @@ pub fn start_watchdog() {
             .is_ok()
             && prev - 1 == 0
         {
-            error!("watchdog expired (host stopped pinging) — tearing down all monitors");
-            disconnect_all_monitors();
+            // About to fire. Serialize against do_add/do_remove (so we never tear an entry out from
+            // under an in-flight ADD), then RE-CHECK the countdown under the lock: if a concurrent
+            // IOCTL (PING/ADD) reset it while we were acquiring the lock, the host is alive — abort.
+            let _op = MONITOR_OP_LOCK.lock().unwrap();
+            if WATCHDOG_COUNTDOWN.load(Ordering::Relaxed) == 0 {
+                error!("watchdog expired (host stopped pinging) — tearing down stale monitors");
+                disconnect_all_monitors_locked(false);
+            }
         }
     });
 }

packaging/windows/vdisplay-driver/pf-vdisplay/src/direct_3d_device.rs

@@ -1,3 +1,5 @@
+use std::sync::atomic::{AtomicI32, Ordering};
+
 use windows::{
     core::Error,
     Win32::{
@@ -29,13 +31,19 @@ impl From<&'static str> for Direct3DError {
     }
 }
 
+/// DIAGNOSTIC: live `Direct3DDevice` count. Each one holds an `ID3D11Device` whose NVIDIA UMD spawns
+/// ~dozens of worker threads; if this climbs without bound across reconnects, devices are leaking.
+pub static LIVE_DEVICES: AtomicI32 = AtomicI32::new(0);
+
 #[derive(Debug)]
 pub struct Direct3DDevice {
     // The following are already refcounted, so they're safe to use directly without additional drop impls
     _dxgi_factory: IDXGIFactory5,
     _adapter: IDXGIAdapter1,
     pub device: ID3D11Device,
-    _device_context: ID3D11DeviceContext,
+    /// The single (SINGLETHREADED) immediate context — used by the frame-push publisher's
+    /// `CopyResource` on the swap-chain processor thread (the one thread this device is touched from).
+    pub device_context: ID3D11DeviceContext,
 }
 
 impl Direct3DDevice {
@@ -67,11 +75,21 @@ impl Direct3DDevice {
         let device = device.ok_or("ID3D11Device not found")?;
         let device_context = device_context.ok_or("ID3D11DeviceContext not found")?;
 
+        let live = LIVE_DEVICES.fetch_add(1, Ordering::Relaxed) + 1;
+        log::error!("Direct3DDevice::init OK — live D3D devices = {live}");
+
         Ok(Self {
             _dxgi_factory: dxgi_factory,
             _adapter: adapter,
             device,
-            _device_context: device_context,
+            device_context,
         })
     }
 }
+
+impl Drop for Direct3DDevice {
+    fn drop(&mut self) {
+        let live = LIVE_DEVICES.fetch_sub(1, Ordering::Relaxed) - 1;
+        log::error!("Direct3DDevice::drop — live D3D devices = {live}");
+    }
+}

packaging/windows/vdisplay-driver/pf-vdisplay/src/edid.rs

@@ -1,114 +1,118 @@
-use std::{array::TryFromSliceError, ops::Deref};
+//! The 256-byte EDID the pf-vdisplay driver hands IddCx for each virtual monitor: a 128-byte EDID 1.4
+//! base block + a **CTA-861.3 extension** that advertises HDR — a BT.2020 Colorimetry Data Block and an
+//! HDR Static Metadata Data Block declaring the SMPTE ST 2084 (PQ) EOTF. Windows reads a display's HDR
+//! capability from this CTA HDR block; without it the monitor is treated as SDR-only regardless of the
+//! IddCx adapter's `CAN_PROCESS_FP16` / `HIGH_COLOR_SPACE` / 10-bit mode caps (the missing piece that
+//! made "Use HDR" never appear for the virtual display). The base block declares EDID 1.4 + 10-bit
+//! digital so the panel's bit depth is unambiguous.
+//!
+//! Identity: manufacturer "PNK" (bytes 8-9), product name "punktfunk" (the 0xFC display descriptor). The
+//! serial-number field (base offset 0x0C, little-endian) encodes the per-monitor index so
+//! `parse_monitor_description` can map an EDID the OS hands back to its monitor; [`Edid::generate_with`]
+//! patches that serial and recomputes BOTH block checksums (base byte 127 + extension byte 255). The
+//! detailed-timing / range-limit descriptors are placeholders — the modes we actually advertise come
+//! from the monitor's stored mode list (`monitor.rs` / `callbacks.rs`), not from parsing this EDID.
 
-use bytemuck::{Pod, Zeroable};
+use std::array::TryFromSliceError;
 
-// A clean, self-contained 128-byte EDID carrying punktfunk's own identity — manufacturer ID "PNK"
-// (bytes 8-9) and product name "punktfunk" (the 0xFC display-descriptor). Derived from the
-// virtual-display-rs base block (a standard, widely-deployed virtual EDID); it deliberately carries NO
-// other driver's bytes or branding. The serial-number field (offset 0x0C) encodes the per-monitor
-// index, so `parse_monitor_description` can map an EDID the OS hands back to its monitor;
-// `generate_with` patches that serial and `gen_checksum` recomputes byte 127 before the EDID reaches
-// IddCx. The detailed-timing / range-limit descriptors are placeholders: the modes we actually
-// advertise come from the monitor's stored mode list (`monitor.rs` / `callbacks.rs`), not from parsing
-// this EDID.
-const _EDID: [u8; 128] = [
-    0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x41, 0xCB, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-    0xFF, 0x21, 0x01, 0x03, 0x80, 0x32, 0x1F, 0x78, 0x07, 0xEE, 0x95, 0xA3, 0x54, 0x4C, 0x99, 0x26,
-    0x0F, 0x50, 0x54, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
-    0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x02, 0x3A, 0x80, 0x18, 0x71, 0x38, 0x2D, 0x40, 0x58, 0x2C,
-    0x45, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1E, 0x00, 0x00, 0x00, 0xFD, 0x00, 0x17, 0xF0, 0x0F,
-    0xFF, 0x0F, 0x00, 0x0A, 0x20, 0x20, 0x20, 0x20, 0x20, 0x20, 0x00, 0x00, 0x00, 0xFC, 0x00, 0x70,
-    0x75, 0x6E, 0x6B, 0x74, 0x66, 0x75, 0x6E, 0x6B, 0x0A, 0x20, 0x20, 0x20, 0x00, 0x00, 0x00, 0x00,
-    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+/// Per-monitor serial number, base-block offset 0x0C, little-endian u32.
+const SERIAL_OFFSET: usize = 0x0C;
+
+/// EDID 1.4 base block (128 bytes). Differs from a plain SDR virtual EDID only by: revision 1.4 (byte
+/// 19 = 0x04), 10-bit digital video input (byte 20 = 0xB0), and one extension present (byte 126 = 0x01).
+/// Byte 127 (checksum) and the serial (0x0C) are filled/patched in [`Edid::generate_with`].
+#[rustfmt::skip]
+const BASE: [u8; 128] = [
+    0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, // fixed header
+    0x41, 0xCB, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // mfr "PNK", product, serial (patched)
+    0xFF, 0x21, 0x01, 0x04, 0xB0, 0x32, 0x1F, 0x78, // week/year, EDID 1.4, 10-bit digital, size, gamma
+    0x03, 0x78, 0xB1, 0xB5, 0x4A, 0x2B, 0xCC, 0x21, // feature (sRGB-default CLEARED), BT.2020 primaries...
+    0x0B, 0x50, 0x54, 0x00, 0x00, 0x00, 0x01, 0x01, // ...BT.2020 primaries, established timings, std timings
+    0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+    0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x02, 0x3A, // std timings, DTD 1 (placeholder preferred timing)
+    0x80, 0x18, 0x71, 0x38, 0x2D, 0x40, 0x58, 0x2C,
+    0x45, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x1E,
+    0x00, 0x00, 0x00, 0xFD, 0x00, 0x17, 0xF0, 0x0F, // display range-limits descriptor
+    0xFF, 0x0F, 0x00, 0x0A, 0x20, 0x20, 0x20, 0x20,
+    0x20, 0x20, 0x00, 0x00, 0x00, 0xFC, 0x00, 0x70, // name descriptor "punktfunk"
+    0x75, 0x6E, 0x6B, 0x74, 0x66, 0x75, 0x6E, 0x6B,
+    0x0A, 0x20, 0x20, 0x20, 0x00, 0x00, 0x00, 0x00, // empty 4th descriptor...
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, // ...byte 126 = 1 extension, byte 127 = checksum
 ];
 
-const EDID_LEN: usize = _EDID.len();
+/// CTA-861.3 extension block (128 bytes), block 1. Header + a Data Block Collection holding the
+/// Colorimetry and HDR Static Metadata data blocks; the rest is padding up to the checksum (byte 255).
+/// `D` (byte 130) marks where DTDs would start (= end of the data blocks); we carry none.
+#[rustfmt::skip]
+const CTA_HEADER: [u8; 4] = [
+    0x02, // CTA Extension tag
+    0x03, // revision 3 (CTA-861.3 — required for the extended-tag data blocks below)
+    0x0F, // D = 15: the (empty) DTD region starts at block byte 15, i.e. data blocks occupy bytes 4..15
+    0x00, // 0 native DTDs; no basic audio; no YCbCr 4:4:4/4:2:2 (RGB-only, matching the wire format)
+];
 
-static EDID: AlignedEdid<EDID_LEN> = AlignedEdid {
-    data: _EDID,
-    _align: [],
-};
+/// Colorimetry Data Block (CTA extended tag 0x05): declare BT.2020 RGB (bit 7). YCbCr variants are left
+/// clear — the IddCx wire format is RGB-only — and the gamut-metadata flags are 0.
+#[rustfmt::skip]
+const COLORIMETRY_DB: [u8; 4] = [
+    0xE3, // tag 0b111 (use-extended-tag) | length 3
+    0x05, // extended tag: Colorimetry
+    0x80, // BT2020RGB (bit 7); xvYCC/sYCC/opRGB/BT2020 YCC/cYCC all clear
+    0x00, // gamut metadata profiles MD0..MD3: none
+];
 
-#[repr(C)]
-struct AlignedEdid<const N: usize> {
-    data: [u8; N],
-    // required to make this type aligned to Edid
-    _align: [Edid; 0],
-}
+/// HDR Static Metadata Data Block (CTA extended tag 0x06): EOTFs = Traditional SDR (ET_0) + SMPTE ST
+/// 2084 / PQ (ET_2); Static Metadata Type 1 (SM_0). Plus the optional desired-content luminance hints
+/// (~993 nit max, ~400 nit max-frame-average, ~0.05 nit min) so the block is complete.
+#[rustfmt::skip]
+const HDR_STATIC_METADATA_DB: [u8; 7] = [
+    0xE6, // tag 0b111 (use-extended-tag) | length 6
+    0x06, // extended tag: HDR Static Metadata
+    0x05, // Supported EOTFs: ET_0 (traditional SDR) | ET_2 (SMPTE ST 2084 / PQ)
+    0x01, // Supported Static Metadata Descriptors: SM_0 (Static Metadata Type 1)
+    0x8A, // Desired Content Max Luminance      (code 138 ≈ 993 nits)
+    0x60, // Desired Content Max Frame-avg Lum. (code  96 = 400 nits)
+    0x12, // Desired Content Min Luminance      (code  18 ≈ 0.05 nits)
+];
 
-impl<const N: usize> AlignedEdid<N> {
-    fn new(data: &[u8]) -> Result<Self, TryFromSliceError> {
-        let data: [u8; N] = data.try_into()?;
-        Ok(Self { data, _align: [] })
-    }
-}
-
-impl<const N: usize> Deref for AlignedEdid<N> {
-    type Target = Edid;
-
-    fn deref(&self) -> &Self::Target {
-        let header = &self.data[..EDID_SIZE];
-        bytemuck::from_bytes(header)
-    }
-}
-
-const EDID_SIZE: usize = std::mem::size_of::<Edid>();
-
-#[repr(C)]
-#[derive(Debug, Copy, Clone, Pod, Zeroable)]
-pub struct Edid {
-    header: [u8; 8],
-    manufacturer_id: [u8; 2],
-    product_code: u16,
-    serial_number: u32,
-    manufacture_week: u8,
-    manufacture_year: u8,
-    version: u8,
-    revision: u8,
-}
+#[derive(Debug, Clone, Copy)]
+pub struct Edid;
 
 impl Edid {
+    /// Build the full 256-byte EDID for monitor `serial`, with both block checksums recomputed.
     pub fn generate_with(serial: u32) -> Vec<u8> {
-        // change serial number in the header
-        let mut header = *EDID;
-        header.serial_number = serial;
-
-        header.generate()
+        let mut edid = [0u8; 256];
+        // Block 0: base.
+        edid[..128].copy_from_slice(&BASE);
+        edid[SERIAL_OFFSET..SERIAL_OFFSET + 4].copy_from_slice(&serial.to_le_bytes());
+        // Block 1: CTA-861.3 extension (header + colorimetry + HDR static metadata; rest stays 0).
+        edid[128..132].copy_from_slice(&CTA_HEADER);
+        edid[132..136].copy_from_slice(&COLORIMETRY_DB);
+        edid[136..143].copy_from_slice(&HDR_STATIC_METADATA_DB);
+        // Each 128-byte block ends in a checksum byte that makes the block sum ≡ 0 (mod 256).
+        Self::fix_block_checksum(&mut edid, 0);
+        Self::fix_block_checksum(&mut edid, 128);
+        edid.to_vec()
     }
 
+    /// Read the per-monitor serial (base offset 0x0C, little-endian) from an EDID the OS handed back.
+    /// Works for the full 256-byte EDID or just the 128-byte base block. Errors (rather than panics) on
+    /// a too-short buffer so the caller can reject a malformed descriptor.
     pub fn get_serial(edid: &[u8]) -> Result<u32, TryFromSliceError> {
-        let edid = AlignedEdid::<EDID_LEN>::new(edid)?;
-        Ok(edid.serial_number)
+        let bytes: [u8; 4] = edid
+            .get(SERIAL_OFFSET..SERIAL_OFFSET + 4)
+            .unwrap_or(&[])
+            .try_into()?;
+        Ok(u32::from_le_bytes(bytes))
     }
 
-    fn generate(&self) -> Vec<u8> {
-        let header = bytemuck::bytes_of(self);
-
-        // slice of monitor edid minus header
-        let data = &EDID.data[EDID_SIZE..];
-
-        // splice together header and the rest of the EDID
-        let mut edid: Vec<u8> = header.iter().chain(data).copied().collect();
-        // regenerate checksum
-        Self::gen_checksum(&mut edid);
-
-        edid
-    }
-
-    fn gen_checksum(data: &mut [u8]) {
-        // important, this is the bare minimum length
-        assert!(data.len() >= 128);
-
-        // slice to the entire data minus the last checksum byte
-        let edid_data = &data[..=126];
-
-        // do checksum calculation
-        let sum: u32 = edid_data.iter().copied().map(u32::from).sum();
-        // this wont ever truncate
-        #[allow(clippy::cast_possible_truncation)]
-        let checksum = (256 - (sum % 256)) as u8;
-
-        // update last byte with new checksum
-        data[127] = checksum;
+    /// Set the trailing byte of the 128-byte block at `start` so the block's bytes sum to 0 (mod 256) —
+    /// the standard EDID block checksum.
+    fn fix_block_checksum(edid: &mut [u8], start: usize) {
+        let sum = edid[start..start + 127]
+            .iter()
+            .fold(0u8, |acc, &b| acc.wrapping_add(b));
+        edid[start + 127] = 0u8.wrapping_sub(sum);
     }
 }

packaging/windows/vdisplay-driver/pf-vdisplay/src/entry.rs

@@ -12,8 +12,10 @@ use wdf_umdf_sys::{
 };
 
 use crate::callbacks::{
-    adapter_commit_modes, adapter_init_finished, assign_swap_chain, device_d0_entry,
-    monitor_get_default_modes, monitor_query_modes, parse_monitor_description, unassign_swap_chain,
+    adapter_commit_modes, adapter_commit_modes2, adapter_init_finished, assign_swap_chain,
+    device_d0_entry, monitor_get_default_modes, monitor_query_modes, monitor_query_modes2,
+    parse_monitor_description, parse_monitor_description2, query_target_info,
+    set_default_hdr_metadata, set_gamma_ramp, unassign_swap_chain,
 };
 use crate::context::DeviceContext;
 use crate::control::device_io_control;
@@ -73,6 +75,15 @@ extern "C-unwind" fn driver_add(
     config.EvtIddCxMonitorGetDefaultDescriptionModes = Some(monitor_get_default_modes);
     config.EvtIddCxMonitorQueryTargetModes = Some(monitor_query_modes);
     config.EvtIddCxAdapterCommitModes = Some(adapter_commit_modes);
+    // IddCx 1.10 *2 mode DDIs (HDR-capable path). The OS prefers these on 1.10; the 1.x callbacks
+    // above stay as the down-level fallback. B1 advertises SDR through them (so behaviour is unchanged);
+    // B2 enables HDR by adding 10 bpc in `wire_bits()`, HIGH_COLOR_SPACE caps, and CAN_PROCESS_FP16.
+    config.EvtIddCxParseMonitorDescription2 = Some(parse_monitor_description2);
+    config.EvtIddCxMonitorQueryTargetModes2 = Some(monitor_query_modes2);
+    config.EvtIddCxAdapterCommitModes2 = Some(adapter_commit_modes2);
+    config.EvtIddCxAdapterQueryTargetInfo = Some(query_target_info);
+    config.EvtIddCxMonitorSetDefaultHdrMetaData = Some(set_default_hdr_metadata);
+    config.EvtIddCxMonitorSetGammaRamp = Some(set_gamma_ramp);
     config.EvtIddCxMonitorAssignSwapChain = Some(assign_swap_chain);
     config.EvtIddCxMonitorUnassignSwapChain = Some(unassign_swap_chain);
     // IddCx redirects device IOCTLs to this callback — our SudoVDA-compatible control plane.

packaging/windows/vdisplay-driver/pf-vdisplay/src/frame_transport.rs

@@ -0,0 +1,424 @@
+//! P2 direct frame push — DRIVER side. The restricted WUDFHost token canNOT create named kernel
+//! objects (proven on the RTX box: it can't even write a world-writable file), so — exactly like the
+//! gamepad UMDF drivers (`crates/punktfunk-host/src/inject/dualsense_windows.rs`: *"the host creates
+//! the section, privileged, with a permissive SDDL so the WUDFHost can open it; the driver maps it"*)
+//! — the **host** creates the shared header + frame-ready event + ring of keyed-mutex textures, and
+//! the driver only **OPENS** them. The driver writes its actual render-adapter LUID + a status code
+//! back into the host-created header (our only driver-visibility channel: UMDF hides OutputDebugString
+//! in ETW and the token can't write files), then copies each acquired swap-chain surface into the next
+//! ring slot and signals the host.
+//!
+//! Host counterpart: `crates/punktfunk-host/src/capture/idd_push.rs` — [`SharedHeader`], [`MAGIC`],
+//! [`RING_LEN`], the driver-status codes and the `Global\` object-name scheme are DUPLICATED
+//! byte-identically there.
+
+use std::sync::atomic::{AtomicPtr, AtomicU32, AtomicU64, Ordering};
+
+use log::info;
+use windows::core::{Interface, HSTRING};
+use windows::Win32::Foundation::{CloseHandle, HANDLE};
+use windows::Win32::Graphics::Direct3D11::{
+    ID3D11Device, ID3D11Device1, ID3D11DeviceContext, ID3D11Texture2D, D3D11_TEXTURE2D_DESC,
+};
+use windows::Win32::Graphics::Dxgi::IDXGIKeyedMutex;
+use windows::Win32::System::Memory::{
+    MapViewOfFile, OpenFileMappingW, UnmapViewOfFile, FILE_MAP_ALL_ACCESS,
+    MEMORY_MAPPED_VIEW_ADDRESS,
+};
+use windows::Win32::System::Threading::{OpenEventW, SetEvent, SYNCHRONIZATION_ACCESS_RIGHTS};
+
+// --- kept byte-identical with the host (idd_push.rs) ---
+pub const MAGIC: u32 = 0x4456_4650;
+/// Kept for parity with the host's duplicated protocol header (the host writes it).
+#[allow(dead_code)]
+pub const VERSION: u32 = 1;
+/// Ring slots. 6 (was 3) gives ample headroom so this 0 ms-timeout publish always finds a free slot
+/// while the host briefly holds one across the convert/copy into its output ring and the depth-2
+/// pipelined encode runs. MUST equal the host's `RING_LEN` (idd_push.rs) — both are rebuilt together;
+/// a mismatch corrupts the slot mapping.
+pub const RING_LEN: u32 = 6;
+const DXGI_SHARED_RESOURCE_RW: u32 = 0x8000_0000 | 0x1;
+/// SYNCHRONIZE | EVENT_MODIFY_STATE — the driver waits on (no) and SIGNALS the event.
+const EVENT_ACCESS: u32 = 0x0010_0000 | 0x0002;
+const WAIT_TIMEOUT_HRESULT: i32 = 0x0000_0102;
+
+/// `driver_status` values the driver writes into the host header (the host logs them on a timeout).
+/// `NONE` is the host's initial value (kept for parity).
+#[allow(dead_code)]
+pub const DRV_STATUS_NONE: u32 = 0;
+pub const DRV_STATUS_OPENED: u32 = 1;
+pub const DRV_STATUS_TEX_FAIL: u32 = 2;
+pub const DRV_STATUS_NO_DEVICE1: u32 = 3;
+
+#[repr(C)]
+pub struct SharedHeader {
+    pub magic: u32,
+    pub version: u32,
+    pub generation: u32,
+    pub ring_len: u32,
+    pub width: u32,
+    pub height: u32,
+    pub dxgi_format: u32,
+    pub _pad: u32,
+    /// `(seq << 8) | slot` — DRIVER-written after each copy; host loads it `Acquire`.
+    pub latest: u64,
+    pub qpc_pts: u64,
+    /// DRIVER-written: the adapter the swap-chain actually renders on (so the host can detect a
+    /// mismatch with the textures it created and report it).
+    pub driver_render_luid_low: u32,
+    pub driver_render_luid_high: i32,
+    /// DRIVER-written status (visibility channel).
+    pub driver_status: u32,
+    pub driver_status_detail: u32,
+}
+
+pub fn hdr_name(target_id: u32) -> String {
+    format!("Global\\pfvd-hdr-{target_id}")
+}
+pub fn evt_name(target_id: u32) -> String {
+    format!("Global\\pfvd-evt-{target_id}")
+}
+pub fn tex_name(target_id: u32, generation: u32, slot: u32) -> String {
+    format!("Global\\pfvd-tex-{target_id}-{generation}-{slot}")
+}
+// --------------------------------------------------------
+
+// ===== Bring-up debug channel (fixed-name, host-created) =====
+// UMDF hides the driver's OutputDebugString (ETW) and the restricted token can't write files, so this
+// fixed-name `Global\pfvd-dbg` block — created by the host with the permissive SDDL — is how the driver
+// reports what it's doing, INDEPENDENT of the per-target header (which is the thing under test). The
+// host reads + logs these counters. Duplicated in `idd_push.rs`.
+#[repr(C)]
+pub struct DebugBlock {
+    pub magic: u32,
+    /// ++ each `run_core` entry — proves the swap-chain processor runs at all.
+    pub run_core_entries: u32,
+    /// The `target_id` the driver resolved for naming (mismatch vs the host = the bug).
+    pub resolved_target_id: u32,
+    /// ++ each header-open attempt.
+    pub header_open_attempts: u32,
+    /// Last header-open error (win32/HRESULT).
+    pub last_open_error: u32,
+    /// 1 once the driver opened the per-target header.
+    pub header_opened: u32,
+    pub render_luid_low: u32,
+    pub render_luid_high: i32,
+    /// ++ each acquired swap-chain frame — proves frames flow (or the display is idle).
+    pub frames_acquired: u32,
+    pub _pad: u32,
+}
+
+static DBG_PTR: AtomicPtr<DebugBlock> = AtomicPtr::new(std::ptr::null_mut());
+
+/// Map the host-created debug block on first use (fixed name). Returns null until the host creates it.
+fn dbg_block() -> *mut DebugBlock {
+    let p = DBG_PTR.load(Ordering::Acquire);
+    if !p.is_null() {
+        return p;
+    }
+    let Ok(map) = (unsafe {
+        OpenFileMappingW(FILE_MAP_ALL_ACCESS.0, false, &HSTRING::from("Global\\pfvd-dbg"))
+    }) else {
+        return std::ptr::null_mut();
+    };
+    let view = unsafe { MapViewOfFile(map, FILE_MAP_ALL_ACCESS, 0, 0, std::mem::size_of::<DebugBlock>()) };
+    if view.Value.is_null() {
+        unsafe {
+            let _ = CloseHandle(map);
+        }
+        return std::ptr::null_mut();
+    }
+    let np = view.Value.cast::<DebugBlock>();
+    match DBG_PTR.compare_exchange(std::ptr::null_mut(), np, Ordering::AcqRel, Ordering::Acquire) {
+        Ok(_) => np, // we win; intentionally leak the handle (diagnostic, process-lifetime)
+        Err(existing) => {
+            unsafe {
+                let _ = UnmapViewOfFile(view);
+                let _ = CloseHandle(map);
+            }
+            existing
+        }
+    }
+}
+
+pub fn dbg_run_core_entry() {
+    let p = dbg_block();
+    if !p.is_null() {
+        unsafe {
+            (*(std::ptr::addr_of_mut!((*p).run_core_entries) as *const AtomicU32))
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+}
+
+pub fn dbg_frame() {
+    let p = dbg_block();
+    if !p.is_null() {
+        unsafe {
+            (*(std::ptr::addr_of_mut!((*p).frames_acquired) as *const AtomicU32))
+                .fetch_add(1, Ordering::Relaxed);
+        }
+    }
+}
+
+/// Record the target id + render LUID the driver will use to name the shared objects.
+pub fn dbg_set_target(target_id: u32, render_luid_low: u32, render_luid_high: i32) {
+    let p = dbg_block();
+    if !p.is_null() {
+        unsafe {
+            (*p).resolved_target_id = target_id;
+            (*p).render_luid_low = render_luid_low;
+            (*p).render_luid_high = render_luid_high;
+        }
+    }
+}
+
+/// Record a header-open attempt + its error (0 = success).
+pub fn dbg_header_attempt(error: u32, opened: bool) {
+    let p = dbg_block();
+    if !p.is_null() {
+        unsafe {
+            (*(std::ptr::addr_of_mut!((*p).header_open_attempts) as *const AtomicU32))
+                .fetch_add(1, Ordering::Relaxed);
+            (*p).last_open_error = error;
+            if opened {
+                (*p).header_opened = 1;
+            }
+        }
+    }
+}
+
+struct Slot {
+    tex: ID3D11Texture2D,
+    mutex: IDXGIKeyedMutex,
+}
+
+/// Publishes acquired swap-chain surfaces into the HOST-created ring. Owned by the swap-chain
+/// processor thread; attached lazily once the host has created the shared objects.
+pub struct FramePublisher {
+    context: ID3D11DeviceContext,
+    map: HANDLE,
+    header: *mut SharedHeader,
+    event: HANDLE,
+    slots: Vec<Slot>,
+    next: u32,
+    seq: u64,
+    /// The host-created ring textures' DXGI format (from the shared header). A swap-chain surface whose
+    /// format differs (e.g. an FP16 HDR frame vs a BGRA ring) is dropped in `publish` — CopyResource
+    /// needs matching formats.
+    ring_format: u32,
+    /// The ring generation this publisher attached to. The host BUMPS the header generation when it
+    /// recreates the ring at a new format mid-session (the display's HDR mode flipped) — [`Self::is_stale`]
+    /// detects that so `run_core` re-attaches to the new-format textures instead of dropping every frame.
+    generation: u32,
+}
+
+// SAFETY: created and used only on the swap-chain processor thread.
+unsafe impl Send for FramePublisher {}
+
+impl FramePublisher {
+    /// Try ONCE to attach to the host-created shared objects. Returns `Err` cheaply if the host hasn't
+    /// created/published them yet — the drain loop retries periodically, so a non-IDD-push session
+    /// just keeps draining with no stall.
+    pub fn try_open(
+        target_id: u32,
+        render_luid_low: u32,
+        render_luid_high: i32,
+        device: &ID3D11Device,
+        context: &ID3D11DeviceContext,
+    ) -> windows::core::Result<Self> {
+        // 1. Open the host-created header (RW). Err if the host hasn't created it yet.
+        let map = unsafe {
+            OpenFileMappingW(
+                FILE_MAP_ALL_ACCESS.0,
+                false,
+                &HSTRING::from(hdr_name(target_id)),
+            )?
+        };
+        let view =
+            unsafe { MapViewOfFile(map, FILE_MAP_ALL_ACCESS, 0, 0, std::mem::size_of::<SharedHeader>()) };
+        if view.Value.is_null() {
+            unsafe {
+                let _ = CloseHandle(map);
+            }
+            return Err(windows::core::Error::from_win32());
+        }
+        let header = view.Value.cast::<SharedHeader>();
+
+        // 2. Report our render adapter to the host immediately (lets it detect a mismatch).
+        unsafe {
+            (*header).driver_render_luid_low = render_luid_low;
+            (*header).driver_render_luid_high = render_luid_high;
+        }
+
+        // 3. The host sets magic==MAGIC only once the ring textures exist. Not ready → retry later.
+        let magic =
+            unsafe { (*(std::ptr::addr_of!((*header).magic) as *const AtomicU32)).load(Ordering::Acquire) };
+        if magic != MAGIC {
+            unsafe {
+                let _ = UnmapViewOfFile(MEMORY_MAPPED_VIEW_ADDRESS { Value: header.cast() });
+                let _ = CloseHandle(map);
+            }
+            return Err(windows::core::Error::from_win32());
+        }
+        let (generation, ring_len) =
+            unsafe { ((*header).generation, (*header).ring_len.min(RING_LEN)) };
+
+        // 4. Open the event (SYNCHRONIZE | EVENT_MODIFY_STATE so we can SetEvent).
+        let event = match unsafe {
+            OpenEventW(
+                SYNCHRONIZATION_ACCESS_RIGHTS(EVENT_ACCESS),
+                false,
+                &HSTRING::from(evt_name(target_id)),
+            )
+        } {
+            Ok(e) => e,
+            Err(e) => {
+                unsafe {
+                    let _ = UnmapViewOfFile(MEMORY_MAPPED_VIEW_ADDRESS { Value: header.cast() });
+                    let _ = CloseHandle(map);
+                }
+                return Err(e);
+            }
+        };
+
+        // 5. Open device1 + the ring textures the host created (same render adapter required).
+        let device1: ID3D11Device1 = match device.cast() {
+            Ok(d) => d,
+            Err(e) => {
+                unsafe {
+                    (*header).driver_status = DRV_STATUS_NO_DEVICE1;
+                    let _ = CloseHandle(event);
+                    let _ = UnmapViewOfFile(MEMORY_MAPPED_VIEW_ADDRESS { Value: header.cast() });
+                    let _ = CloseHandle(map);
+                }
+                return Err(e);
+            }
+        };
+        let mut slots = Vec::new();
+        for k in 0..ring_len {
+            let name = HSTRING::from(tex_name(target_id, generation, k));
+            let opened: windows::core::Result<ID3D11Texture2D> =
+                unsafe { device1.OpenSharedResourceByName(&name, DXGI_SHARED_RESOURCE_RW) };
+            match opened {
+                Ok(tex) => match tex.cast::<IDXGIKeyedMutex>() {
+                    Ok(mutex) => slots.push(Slot { tex, mutex }),
+                    Err(e) => {
+                        unsafe {
+                            (*header).driver_status = DRV_STATUS_TEX_FAIL;
+                            (*header).driver_status_detail = e.code().0 as u32;
+                            let _ = CloseHandle(event);
+                            let _ = UnmapViewOfFile(MEMORY_MAPPED_VIEW_ADDRESS { Value: header.cast() });
+                            let _ = CloseHandle(map);
+                        }
+                        return Err(e);
+                    }
+                },
+                Err(e) => {
+                    // Most likely a render-adapter mismatch (the host made the textures on a different
+                    // GPU than the swap-chain renders on). Tell the host so it can report it.
+                    unsafe {
+                        (*header).driver_status = DRV_STATUS_TEX_FAIL;
+                        (*header).driver_status_detail = e.code().0 as u32;
+                        let _ = CloseHandle(event);
+                        let _ = UnmapViewOfFile(MEMORY_MAPPED_VIEW_ADDRESS { Value: header.cast() });
+                        let _ = CloseHandle(map);
+                    }
+                    return Err(e);
+                }
+            }
+        }
+
+        unsafe {
+            (*header).driver_status = DRV_STATUS_OPENED;
+        }
+        info!("frame-push(driver): attached to host ring gen {generation} ({ring_len} slots)");
+        Ok(Self {
+            context: context.clone(),
+            map,
+            header,
+            event,
+            slots,
+            next: 0,
+            seq: 0,
+            ring_format: unsafe { (*header).dxgi_format },
+            generation,
+        })
+    }
+
+    #[inline]
+    fn latest_cell(&self) -> &AtomicU64 {
+        unsafe { &*(std::ptr::addr_of!((*self.header).latest) as *const AtomicU64) }
+    }
+
+    /// True once the host has recreated the ring (bumped the header generation) — e.g. the display's
+    /// HDR mode flipped, so the ring format changed (FP16 ⇄ BGRA) and the texture names now carry a new
+    /// generation. `run_core` drops the publisher on this so it re-attaches to the new ring.
+    pub fn is_stale(&self) -> bool {
+        let cur = unsafe {
+            (*(std::ptr::addr_of!((*self.header).generation) as *const AtomicU32))
+                .load(Ordering::Acquire)
+        };
+        cur != self.generation
+    }
+
+    /// Copy `surface` into the next free ring slot and signal the host. Never blocks (0 ms try-acquire).
+    pub fn publish(&mut self, surface: &ID3D11Texture2D) {
+        let ring_len = self.slots.len() as u32;
+        if ring_len == 0 {
+            return;
+        }
+        // B2 format guard: CopyResource needs the surface + ring textures to share a DXGI format. Drop
+        // a frame that doesn't match (e.g. an FP16 HDR surface arriving while the ring is still BGRA,
+        // before B3 makes the ring FP16) instead of corrupting / failing the copy.
+        let mut desc = D3D11_TEXTURE2D_DESC::default();
+        unsafe { surface.GetDesc(&mut desc) };
+        if desc.Format.0 as u32 != self.ring_format {
+            return;
+        }
+        let start = self.next;
+        for attempt in 0..ring_len {
+            let slot = (start + attempt) % ring_len;
+            let s = &self.slots[slot as usize];
+            match unsafe { s.mutex.AcquireSync(0, 0) } {
+                Ok(()) => {
+                    unsafe {
+                        self.context.CopyResource(&s.tex, surface);
+                        let _ = s.mutex.ReleaseSync(0);
+                    }
+                    self.seq = self.seq.wrapping_add(1);
+                    // `latest` = (generation << 40) | (seq << 8) | slot. Stamping the generation lets the
+                    // host REJECT a publish from a stale ring (an old-generation publisher racing the
+                    // host's mid-session ring recreate) so it never consumes an unwritten new-ring slot.
+                    let latest = (u64::from(self.generation) << 40)
+                        | ((self.seq & 0xFFFF_FFFF) << 8)
+                        | u64::from(slot & 0xff);
+                    self.latest_cell().store(latest, Ordering::Release);
+                    unsafe {
+                        let _ = SetEvent(self.event);
+                    }
+                    self.next = (slot + 1) % ring_len;
+                    return;
+                }
+                Err(e) if e.code().0 == WAIT_TIMEOUT_HRESULT => continue,
+                Err(_) => return,
+            }
+        }
+        // All slots busy — drop this frame (never block the swap-chain thread).
+    }
+}
+
+impl Drop for FramePublisher {
+    fn drop(&mut self) {
+        self.slots.clear();
+        unsafe {
+            if !self.header.is_null() {
+                let _ = UnmapViewOfFile(MEMORY_MAPPED_VIEW_ADDRESS {
+                    Value: self.header.cast(),
+                });
+            }
+            let _ = CloseHandle(self.event);
+            let _ = CloseHandle(self.map);
+        }
+    }
+}

packaging/windows/vdisplay-driver/pf-vdisplay/src/lib.rs

@@ -12,6 +12,7 @@ mod control;
 mod direct_3d_device;
 mod edid;
 mod entry;
+mod frame_transport;
 mod helpers;
 mod logger;
 mod monitor;

packaging/windows/vdisplay-driver/pf-vdisplay/src/logger.rs

@@ -1,12 +1,22 @@
-//! Minimal `log` backend that writes to `OutputDebugString` — no `driver-logger`/event-log/`tokio`.
-//! View with DebugView/WinDbg. Keeping the `log` facade lets the ported callbacks/context use
-//! `error!`/`info!`/`debug!` unchanged.
+//! Minimal `log` backend that writes to `OutputDebugString` AND tees to a file — UMDF redirects a
+//! hosted driver's `OutputDebugString` to ETW (invisible to DebugView), so the file tee is how we
+//! actually read driver logs during bring-up. Keeping the `log` facade lets the ported
+//! callbacks/context use `error!`/`info!`/`debug!` unchanged.
+
+use std::fs::OpenOptions;
+use std::io::Write;
+use std::sync::Mutex;
 
 use log::{LevelFilter, Metadata, Record};
 use windows::core::PCSTR;
 use windows::Win32::System::Diagnostics::Debug::OutputDebugStringA;
 
-struct DbgLogger;
+/// World-writable so the restricted WUDFHost token can append. Read it during bring-up.
+const LOG_PATH: &str = r"C:\Users\Public\pfvd-driver.log";
+
+struct DbgLogger {
+    file: Mutex<()>,
+}
 
 impl log::Log for DbgLogger {
     fn enabled(&self, _metadata: &Metadata) -> bool {
@@ -17,12 +27,19 @@ impl log::Log for DbgLogger {
         let msg = format!("[pf-vdisplay] {:<5} {}\0", record.level(), record.args());
         // SAFETY: `msg` is a NUL-terminated byte string valid for the call.
         unsafe { OutputDebugStringA(PCSTR(msg.as_ptr())) };
+        // Tee to the file (best-effort): the real channel during bring-up.
+        let _guard = self.file.lock();
+        if let Ok(mut f) = OpenOptions::new().create(true).append(true).open(LOG_PATH) {
+            let _ = writeln!(f, "{:<5} {}", record.level(), record.args());
+        }
     }
 
     fn flush(&self) {}
 }
 
-static LOGGER: DbgLogger = DbgLogger;
+static LOGGER: DbgLogger = DbgLogger {
+    file: Mutex::new(()),
+};
 
 pub fn init() {
     let _ = log::set_logger(&LOGGER);
@@ -31,4 +48,8 @@ pub fn init() {
     } else {
         LevelFilter::Info
     });
+    // Boot marker so each load is distinguishable in the file.
+    if let Ok(mut f) = OpenOptions::new().create(true).append(true).open(LOG_PATH) {
+        let _ = writeln!(f, "==== pf-vdisplay logger init ====");
+    }
 }

packaging/windows/vdisplay-driver/pf-vdisplay/src/monitor.rs

@@ -6,6 +6,7 @@
 use std::ptr::NonNull;
 use std::sync::atomic::{AtomicU32, AtomicU64};
 use std::sync::{Mutex, OnceLock};
+use std::time::Instant;
 
 use wdf_umdf_sys::{IDDCX_ADAPTER__, IDDCX_MONITOR__};
 
@@ -37,6 +38,10 @@ pub struct MonitorObject {
     pub target_id: u32,
     pub adapter_luid_low: u32,
     pub adapter_luid_high: i32,
+    /// When the entry was pushed (`do_add`). The watchdog skips monitors younger than the host's
+    /// setup window (CCD commit + GDI-name resolve + settle) so a still-initializing monitor is never
+    /// torn down mid-birth during reconnect churn.
+    pub created_at: Instant,
 }
 // SAFETY: the raw IddCx object ptr is framework-managed; access is serialized by MONITOR_MODES.
 unsafe impl Send for MonitorObject {}
@@ -53,9 +58,12 @@ pub static MONITOR_MODES: Mutex<Vec<MonitorObject>> = Mutex::new(Vec::new());
 
 /// Monitor id / EDID-serial counter (unique per created monitor).
 pub static NEXT_ID: AtomicU32 = AtomicU32::new(1);
-/// Watchdog (seconds). The host reads the timeout via GET_WATCHDOG and PINGs to keep alive.
-pub static WATCHDOG_TIMEOUT: AtomicU32 = AtomicU32::new(3);
-pub static WATCHDOG_COUNTDOWN: AtomicU32 = AtomicU32::new(3);
+/// Watchdog (seconds). The host reads the timeout via GET_WATCHDOG and PINGs to keep alive. 8 s (was
+/// 3) gives the host's between-session teardown gap — stop old pinger → CCD display re-attach (a slow
+/// `SetDisplayConfig`) → REMOVE — headroom, so the watchdog doesn't spuriously fire during reconnect
+/// churn. The host derives its PING interval from this (timeout/3), so it auto-adjusts.
+pub static WATCHDOG_TIMEOUT: AtomicU32 = AtomicU32::new(8);
+pub static WATCHDOG_COUNTDOWN: AtomicU32 = AtomicU32::new(8);
 /// The preferred render adapter LUID set via SET_RENDER_ADAPTER, packed `(high<<32)|low`. 0 = none.
 pub static PREFERRED_RENDER_ADAPTER: AtomicU64 = AtomicU64::new(0);
 

packaging/windows/vdisplay-driver/pf-vdisplay/src/swap_chain_processor.rs

@@ -4,29 +4,39 @@ use std::{
         Arc,
     },
     thread::{self, JoinHandle},
+    time::Duration,
 };
 
 use log::{debug, error};
 use wdf_umdf::{
-    IddCxSwapChainFinishedProcessingFrame, IddCxSwapChainReleaseAndAcquireBuffer,
+    IddCxSwapChainFinishedProcessingFrame, IddCxSwapChainReleaseAndAcquireBuffer2,
     IddCxSwapChainSetDevice, WdfObjectDelete,
 };
 use wdf_umdf_sys::{
-    HANDLE, IDARG_IN_SWAPCHAINSETDEVICE, IDARG_OUT_RELEASEANDACQUIREBUFFER, IDDCX_SWAPCHAIN,
-    NTSTATUS, WAIT_TIMEOUT, WDFOBJECT,
+    HANDLE, IDARG_IN_RELEASEANDACQUIREBUFFER2, IDARG_IN_SWAPCHAINSETDEVICE,
+    IDARG_OUT_RELEASEANDACQUIREBUFFER2, IDDCX_SWAPCHAIN, NTSTATUS, WAIT_TIMEOUT, WDFOBJECT,
 };
 use windows::{
     core::{w, Interface},
     Win32::{
         Foundation::HANDLE as WHANDLE,
-        Graphics::Dxgi::IDXGIDevice,
+        Graphics::{
+            Direct3D11::ID3D11Texture2D,
+            Dxgi::{IDXGIDevice, IDXGIResource},
+        },
         System::Threading::{
             AvRevertMmThreadCharacteristics, AvSetMmThreadCharacteristicsW, WaitForSingleObject,
         },
     },
 };
 
-use crate::{direct_3d_device::Direct3DDevice, helpers::Sendable};
+use crate::{
+    direct_3d_device::Direct3DDevice,
+    frame_transport::{
+        dbg_frame, dbg_header_attempt, dbg_run_core_entry, dbg_set_target, FramePublisher,
+    },
+    helpers::Sendable,
+};
 
 pub struct SwapChainProcessor {
     terminate: Arc<AtomicBool>,
@@ -47,8 +57,11 @@ impl SwapChainProcessor {
     pub fn run(
         &mut self,
         swap_chain: IDDCX_SWAPCHAIN,
-        device: Direct3DDevice,
+        device: Arc<Direct3DDevice>,
         available_buffer_event: HANDLE,
+        target_id: u32,
+        render_luid_low: u32,
+        render_luid_high: i32,
     ) {
         let available_buffer_event = unsafe { Sendable::new(available_buffer_event) };
         let swap_chain = unsafe { Sendable::new(swap_chain) };
@@ -64,7 +77,17 @@ impl SwapChainProcessor {
                 return;
             };
 
-            Self::run_core(*swap_chain, &device, *available_buffer_event, &terminate);
+            Self::run_core(
+                *swap_chain,
+                &device,
+                *available_buffer_event,
+                &terminate,
+                target_id,
+                render_luid_low,
+                render_luid_high,
+            );
+
+            error!("run_core RETURNED (target={target_id}) — deleting swap-chain, device drops next");
 
             let res = unsafe { WdfObjectDelete(*swap_chain as WDFOBJECT) };
             if let Err(e) = res {
@@ -87,31 +110,140 @@ impl SwapChainProcessor {
         device: &Direct3DDevice,
         available_buffer_event: HANDLE,
         terminate: &AtomicBool,
+        target_id: u32,
+        render_luid_low: u32,
+        render_luid_high: i32,
     ) {
-        let dxgi_device = device.device.cast::<IDXGIDevice>();
-        let Ok(dxgi_device) = dxgi_device else {
-            error!("Failed to cast ID3D11Device to IDXGIDevice: {dxgi_device:?}");
-            return;
-        };
+        // P2 direct frame push: lazily ATTACH to the HOST-created shared ring. The restricted UMDF
+        // token can't create named objects, so the host creates the header + event + textures and we
+        // only OPEN them once they appear (`try_open`). Until then we just drain — exactly the P1
+        // behaviour — so a non-IDD-push session never stalls. Retried every ~30 frames.
+        let mut publisher: Option<FramePublisher> = None;
+        let mut frames_since_try: u32 = u32::MAX; // attach attempt on the first acquired frame
 
+        // Bring-up debug: prove run_core ran + record the target/render LUID we'll name objects with.
+        dbg_run_core_entry();
+        dbg_set_target(target_id, render_luid_low, render_luid_high);
+
+        // SetDevice fails (0x887A0026, FACILITY_DXGI) when the monitor briefly flaps INACTIVE during
+        // topology activation — the OS unassigns + re-assigns the swap-chain, and a fresh run_core thread
+        // can lose the race to the unassign. Retry briefly so a stable re-assign binds the device instead
+        // of giving up on the first transient failure. `terminate` (set when the OS unassigns + drops the
+        // processor) breaks us out promptly.
+        // Cast to IDXGIDevice ONCE and BORROW it to the swap-chain across all retries. The previous
+        // code re-cast + `into_raw()`'d on EVERY attempt — and a flapping monitor fails several
+        // attempts per session — so each failure orphaned one IDXGIDevice reference, pinning the D3D
+        // device so it (and its ~dozen D3D worker threads + tens of MB of VRAM) was NEVER freed when
+        // the processor dropped. That leaked ~71 threads / ~57 MB VRAM per reconnect until the driver
+        // choked and sessions fell to 0 bytes. `as_raw()` keeps our single reference (released right
+        // after the loop); IddCx AddRefs its own on success, and `device` keeps the object alive for
+        // the drain loop regardless.
+        let dxgi_device = match device.device.cast::<IDXGIDevice>() {
+            Ok(d) => d,
+            Err(e) => {
+                error!("Failed to cast ID3D11Device to IDXGIDevice: {e:?}");
+                return;
+            }
+        };
         let set_device = IDARG_IN_SWAPCHAINSETDEVICE {
-            pDevice: dxgi_device.into_raw().cast(),
+            pDevice: dxgi_device.as_raw().cast(),
         };
-
-        let res = unsafe { IddCxSwapChainSetDevice(swap_chain, &set_device) };
-        if res.is_err() {
-            debug!("Failed to set swapchain device: {res:?}");
+        let mut set_ok = false;
+        let mut terminated = false;
+        for attempt in 0..60u32 {
+            if terminate.load(Ordering::Relaxed) {
+                error!("run_core: terminated during SetDevice (attempt {attempt}, target={target_id})");
+                terminated = true;
+                break;
+            }
+            let res = unsafe { IddCxSwapChainSetDevice(swap_chain, &set_device) };
+            if res.is_ok() {
+                set_ok = true;
+                error!("run_core: SetDevice OK (target={target_id}, attempt={attempt}) — entering drain loop");
+                break;
+            }
+            if attempt == 0 {
+                debug!("run_core: SetDevice attempt 0 failed ({res:?}) — retrying up to 60x@50ms (monitor may be flapping)");
+            }
+            thread::sleep(Duration::from_millis(50));
+        }
+        // Release our borrowed device reference — IddCx holds its own now, or we gave up. (Explicit
+        // drop so NLL can't release it mid-loop while the swap-chain still references the raw ptr.)
+        drop(dxgi_device);
+        if !set_ok {
+            if !terminated {
+                error!("run_core: SetDevice never succeeded after retries (target={target_id}) — giving up");
+            }
             return;
         }
 
+        let mut logged_pending = false;
+        let mut logged_frame = false;
         loop {
-            let mut buffer = IDARG_OUT_RELEASEANDACQUIREBUFFER::default();
-            let hr: NTSTATUS =
-                unsafe { IddCxSwapChainReleaseAndAcquireBuffer(swap_chain, &mut buffer).into() };
+            // Check terminate at the TOP, every iteration. The success branch below does NOT re-check
+            // it, so during a CONTINUOUS frame burst (DWM rendering the freshly-activated desktop) a
+            // thread that the OS unassigns — or that `free_swap_chain_processor` is dropping — never
+            // sees the flag and loops on, pinning its D3D device (and ~36 NVIDIA worker threads). That
+            // is THE reconnect leak: it only reproduced at full speed, because cdb's pacing forced
+            // E_PENDING gaps (which DO check terminate) and masked it. Without this, `SwapChainProcessor::drop`'s
+            // join can also block until the burst ends.
+            if terminate.load(Ordering::Relaxed) {
+                break;
+            }
+            // The host recreates the shared ring (new format) mid-session when the display's HDR mode
+            // flips — it bumps the header generation. Detect that and drop the publisher so we re-attach
+            // to the new-format textures below; otherwise we'd keep CopyResource'ing into the stale ring,
+            // whose format now mismatches the surface → the publish() format-guard drops every frame and
+            // the stream freezes until the next swap-chain recreate.
+            if publisher.as_ref().is_some_and(FramePublisher::is_stale) {
+                publisher = None;
+                frames_since_try = u32::MAX; // re-attach immediately
+            }
+            // Lazy-attach (rate-limited) at the loop TOP so we keep trying even while the display is
+            // idle (E_PENDING / no frames presented yet), not only when a frame is acquired. `try_open`
+            // is a cheap OpenFileMapping that fails fast until the host has created the ring.
+            if publisher.is_none() {
+                if frames_since_try >= 30 {
+                    frames_since_try = 0;
+                    match FramePublisher::try_open(
+                        target_id,
+                        render_luid_low,
+                        render_luid_high,
+                        &device.device,
+                        &device.device_context,
+                    ) {
+                        Ok(p) => {
+                            dbg_header_attempt(0, true);
+                            publisher = Some(p);
+                        }
+                        Err(e) => dbg_header_attempt(e.code().0 as u32, false),
+                    }
+                } else {
+                    frames_since_try += 1;
+                }
+            }
+
+            // B2: ...Buffer2 is required once CAN_PROCESS_FP16 is set. AcquireSystemMemoryBuffer=FALSE
+            // keeps the GPU surface (out.MetaData.pSurface). The surface format varies per-frame —
+            // FP16 (R16G16B16A16_FLOAT) in HDR, BGRA in SDR — and the publisher's format guard handles
+            // a frame that doesn't match the ring until B3 makes the ring FP16.
+            let mut in_args = IDARG_IN_RELEASEANDACQUIREBUFFER2 {
+                #[allow(clippy::cast_possible_truncation)]
+                Size: std::mem::size_of::<IDARG_IN_RELEASEANDACQUIREBUFFER2>() as u32,
+                AcquireSystemMemoryBuffer: 0,
+            };
+            let mut buffer = IDARG_OUT_RELEASEANDACQUIREBUFFER2::default();
+            let hr: NTSTATUS = unsafe {
+                IddCxSwapChainReleaseAndAcquireBuffer2(swap_chain, &mut in_args, &mut buffer).into()
+            };
 
             #[allow(clippy::items_after_statements)]
             const E_PENDING: u32 = 0x8000_000A;
             if u32::from(hr) == E_PENDING {
+                if !logged_pending {
+                    error!("run_core: E_PENDING (target={target_id}) — swap-chain valid but DWM has composed NO frame yet");
+                    logged_pending = true;
+                }
                 let wait_result =
                     unsafe { WaitForSingleObject(WHANDLE(available_buffer_event.cast()), 16).0 };
 
@@ -130,8 +262,29 @@ impl SwapChainProcessor {
                 // The wait was cancelled or something unexpected happened
                 break;
             } else if hr.is_success() {
+                if !logged_frame {
+                    error!("run_core: FIRST FRAME acquired (target={target_id}) — DWM IS compositing the virtual display!");
+                    logged_frame = true;
+                }
+                dbg_frame(); // bring-up: prove frames actually flow (vs an idle display)
                 // This is the most performance-critical section of code in an IddCx driver. It's important that whatever
                 // is done with the acquired surface be finished as quickly as possible.
+                //
+                // P2: copy the acquired surface into the shared ring BEFORE FinishedProcessingFrame
+                // (the surface is valid until the next ReleaseAndAcquire). The pointer is BORROWED —
+                // `from_raw_borrowed` does not take IddCx's refcount — and the GPU-side copy is ordered
+                // before the consumer via the slot keyed mutex. (Attach happens at the loop top.)
+                if let Some(pub_) = publisher.as_mut() {
+                    let raw = buffer.MetaData.pSurface as *mut core::ffi::c_void;
+                    if !raw.is_null() {
+                        if let Some(res) = unsafe { IDXGIResource::from_raw_borrowed(&raw) } {
+                            if let Ok(tex) = res.cast::<ID3D11Texture2D>() {
+                                pub_.publish(&tex);
+                            }
+                        }
+                    }
+                }
+
                 let hr = unsafe { IddCxSwapChainFinishedProcessingFrame(swap_chain) };
 
                 if hr.is_err() {

packaging/windows/vdisplay-driver/wdf-umdf-sys/build.rs

@@ -7,7 +7,10 @@ use winreg::enums::HKEY_LOCAL_MACHINE;
 use winreg::RegKey;
 
 const UMDF_V: &str = "2.31";
-const IDDCX_V: &str = "1.4";
+// Bumped 1.4 -> 1.10 for HDR/FP16 support (IDDCX_ADAPTER_FLAGS_CAN_PROCESS_FP16,
+// IddCxSwapChainReleaseAndAcquireBuffer2, the *2 mode/metadata DDIs). 1.10 is a superset of 1.4, so
+// existing call sites keep working; the new HDR DDIs become available to bind.
+const IDDCX_V: &str = "1.10";
 
 #[derive(Debug, thiserror::Error)]
 enum Error {

packaging/windows/vdisplay-driver/wdf-umdf/src/iddcx.rs

@@ -7,7 +7,8 @@ use wdf_umdf_sys::{
     IDARG_IN_ADAPTERSETRENDERADAPTER, IDARG_IN_ADAPTER_INIT, IDARG_IN_MONITORCREATE,
     IDARG_IN_QUERY_HWCURSOR, IDARG_IN_SETUP_HWCURSOR, IDARG_IN_SWAPCHAINSETDEVICE,
     IDARG_OUT_ADAPTER_INIT, IDARG_OUT_MONITORARRIVAL, IDARG_OUT_MONITORCREATE,
-    IDARG_OUT_QUERY_HWCURSOR, IDARG_OUT_RELEASEANDACQUIREBUFFER, IDDCX_ADAPTER, IDDCX_MONITOR,
+    IDARG_IN_RELEASEANDACQUIREBUFFER2, IDARG_OUT_QUERY_HWCURSOR, IDARG_OUT_RELEASEANDACQUIREBUFFER,
+    IDARG_OUT_RELEASEANDACQUIREBUFFER2, IDDCX_ADAPTER, IDDCX_MONITOR,
     IDDCX_SWAPCHAIN, IDD_CX_CLIENT_CONFIG, NTSTATUS, WDFDEVICE, WDFDEVICE_INIT,
 };
 
@@ -236,6 +237,30 @@ pub unsafe fn IddCxSwapChainReleaseAndAcquireBuffer(
     )
 }
 
+/// IddCx 1.10 HDR variant — required once the adapter sets `CAN_PROCESS_FP16`. Provides per-frame
+/// `IDDCX_METADATA2` (surface colour space, HDR metadata, SDR white level).
+///
+/// # Safety
+/// None. User is responsible for safety.
+#[rustfmt::skip]
+pub unsafe fn IddCxSwapChainReleaseAndAcquireBuffer2(
+    // in
+    SwapChainObject: IDDCX_SWAPCHAIN,
+    // in
+    pInArgs: &mut IDARG_IN_RELEASEANDACQUIREBUFFER2,
+    // out
+    pOutArgs: &mut IDARG_OUT_RELEASEANDACQUIREBUFFER2
+) -> Result<NTSTATUS, IddCxError> {
+    IddCxCall!(
+        true,
+        IddCxSwapChainReleaseAndAcquireBuffer2(
+            SwapChainObject,
+            pInArgs,
+            pOutArgs
+        )
+    )
+}
+
 /// # Safety
 ///
 /// None. User is responsible for safety.