dlidusb4.dll memory leak and WDF verifier failures

The-Hof · Today, 04:03 AM

dlidusb4.dll leaks memory to 1.4 GB then fails WDF verifier — began 15 July 2026, correlates with KB5101650

The DisplayLink user-mode display driver dlidusb4.dll is leaking memory in its WUDFHost process and eventually crashing. Each crash takes down every display endpoint on the dock: the system slows, all monitors go black, and the displays recover once Windows restarts the devices. There is no bugcheck and no reboot.

WUDFHost heap dumps captured at the moment of each crash:

Date Heap dump size
2026-07-31 237.8 MB
2026-08-04 1455.8 MB

Windows' own leak detector flagged the process independently on 2026-07-22: WER report RADAR_PRE_LEAK_64, P1 WUDFHost.exe, P2 10.0.26100.8875.

After the 4 August crash, the replacement WUDFHost process (PID 30424, started 18:20:09 — the second of the crash) reached 250 MB working set within hours. For comparison, every other WUDFHost instance on the same machine sat between 1.5 MB and 13 MB after two days of uptime.

So the DisplayLink host is running roughly 20–150x larger than any other UMDF host on the system and growing steadily until it fails.

Failure signature

System log, Event ID 10121, Microsoft-Windows-DriverFrameworks-UserMode:

A runtime failure has occurred in user-mode driver dlidusb4.dll and the hosting process has been terminated.

Accompanied by Event 10120 (WUDFHost terminated) and four instances of Event 10111 (dock display endpoints going offline across two device locations, corresponding to the two DisplayLink chips in this dock).

Windows Error Reporting records these as WUDFVerifierFailure:

P5: minkernel\wdf\framework\shared\object\fxverifierbu gcheck.cpp:188 (FxVerifierDriverReportedBugcheck)
P6: dlidusb4.dll
P8: 2.35.0

The P4 verifier code differs between occurrences, suggesting more than one distinct WDF contract violation rather than a single repeating fault:

Date Driver version P4 code
2026-07-15 07:02 12.1.2684.0 501000400010000
2026-07-16 12:12 12.1.2684.0 501000400000200
2026-07-31 08:41 12.1.2684.0 501000400000116
2026-08-04 18:20 12.2.2412.0 501000400010000
Onset and correlation with a Windows update

My System event log is retained back to 9 May 2026. There are no Event 10121 occurrences at any point before 15 July 2026. The driver in use throughout that period (12.1.2684.0) was installed in November 2025 and ran without incident.

The Windows Setup log shows the July 2026 cumulative update KB5101650 (OS build 26200.8875) beginning installation at 23:56 on 14 July 2026. The first dlidusb4.dll crash occurred approximately seven hours later, at 07:02 on 15 July 2026.

For context: Microsoft released out-of-band update KB5121767 on 18 July 2026 specifically to address an Intel Innovation Platform Framework driver regression introduced by KB5101650. That regression also affected this machine (bugcheck 0x50 with the fault in the ipf_lf.sys call path) and is now resolved by the fix. It establishes that KB5101650 caused at least one driver-level regression on this platform. The dlidusb4.dll failures may be a second, so far unreported, consequence of the same update.

Updating to the current DisplayLink release did not help — the 4 August crash occurred on 12.2.2412.0.

System
Lenovo Yoga Pro 9 16IAH10 (machine type 83L0)
Intel Core Ultra 9 285H, 32 GB LPDDR5, NVIDIA RTX 5050 Laptop GPU
Windows 11 25H2, build 26200.8973
Targus DOCK570 (USB-C Universal Quad 4K, 100 W PD, dual DL-6910)
3 external displays via the dock plus the internal laptop panel
Dock enumerates on Intel xHCI controller PCI\VEN_8086&DEV_7EC0
DisplayLink software
Package 12.2.2440.0 (29 June 2026) — the current release
Graphics dlidusb.inf 12.2.2412.0 (19 June 2026)
Audio extension dlusbaudioext.inf 12.2.1708.0
Ethernet dlcdcncm.inf 12.2.1708.0
Previously 12.1.2684.0, which exhibited the same failure
Trigger conditions

Crashes occur predominantly during video conference calls (Microsoft Teams) with all three external displays active — consistent with a leak that accumulates under sustained display activity.

An external Logitech c922 webcam is in use. It has already been moved off the dock onto a separate USB host controller (DEV_777D) to rule out bandwidth contention on the dock's controller. The 4 August crash occurred after that change, so contention does not appear to be a factor.

Available on request

WDF minidumps and heap dumps from C:\ProgramData\Microsoft\WDF\, a DisplayLink Support Tool report, and full event log exports. I can also run a trace if that would help isolate the allocation path.

Today, 04:03 AM	#1
The-Hof Junior Member Join Date: Aug 2026 Posts: 1	dlidusb4.dll memory leak and WDF verifier failures dlidusb4.dll leaks memory to 1.4 GB then fails WDF verifier — began 15 July 2026, correlates with KB5101650 The DisplayLink user-mode display driver dlidusb4.dll is leaking memory in its WUDFHost process and eventually crashing. Each crash takes down every display endpoint on the dock: the system slows, all monitors go black, and the displays recover once Windows restarts the devices. There is no bugcheck and no reboot. WUDFHost heap dumps captured at the moment of each crash: Date Heap dump size 2026-07-31 237.8 MB 2026-08-04 1455.8 MB Windows' own leak detector flagged the process independently on 2026-07-22: WER report RADAR_PRE_LEAK_64, P1 WUDFHost.exe, P2 10.0.26100.8875. After the 4 August crash, the replacement WUDFHost process (PID 30424, started 18:20:09 — the second of the crash) reached 250 MB working set within hours. For comparison, every other WUDFHost instance on the same machine sat between 1.5 MB and 13 MB after two days of uptime. So the DisplayLink host is running roughly 20–150x larger than any other UMDF host on the system and growing steadily until it fails. Failure signature System log, Event ID 10121, Microsoft-Windows-DriverFrameworks-UserMode: A runtime failure has occurred in user-mode driver dlidusb4.dll and the hosting process has been terminated. Accompanied by Event 10120 (WUDFHost terminated) and four instances of Event 10111 (dock display endpoints going offline across two device locations, corresponding to the two DisplayLink chips in this dock). Windows Error Reporting records these as WUDFVerifierFailure: P5: minkernel\wdf\framework\shared\object\fxverifierbu gcheck.cpp:188 (FxVerifierDriverReportedBugcheck) P6: dlidusb4.dll P8: 2.35.0 The P4 verifier code differs between occurrences, suggesting more than one distinct WDF contract violation rather than a single repeating fault: Date Driver version P4 code 2026-07-15 07:02 12.1.2684.0 501000400010000 2026-07-16 12:12 12.1.2684.0 501000400000200 2026-07-31 08:41 12.1.2684.0 501000400000116 2026-08-04 18:20 12.2.2412.0 501000400010000 Onset and correlation with a Windows update My System event log is retained back to 9 May 2026. There are no Event 10121 occurrences at any point before 15 July 2026. The driver in use throughout that period (12.1.2684.0) was installed in November 2025 and ran without incident. The Windows Setup log shows the July 2026 cumulative update KB5101650 (OS build 26200.8875) beginning installation at 23:56 on 14 July 2026. The first dlidusb4.dll crash occurred approximately seven hours later, at 07:02 on 15 July 2026. For context: Microsoft released out-of-band update KB5121767 on 18 July 2026 specifically to address an Intel Innovation Platform Framework driver regression introduced by KB5101650. That regression also affected this machine (bugcheck 0x50 with the fault in the ipf_lf.sys call path) and is now resolved by the fix. It establishes that KB5101650 caused at least one driver-level regression on this platform. The dlidusb4.dll failures may be a second, so far unreported, consequence of the same update. Updating to the current DisplayLink release did not help — the 4 August crash occurred on 12.2.2412.0. System Lenovo Yoga Pro 9 16IAH10 (machine type 83L0) Intel Core Ultra 9 285H, 32 GB LPDDR5, NVIDIA RTX 5050 Laptop GPU Windows 11 25H2, build 26200.8973 Targus DOCK570 (USB-C Universal Quad 4K, 100 W PD, dual DL-6910) 3 external displays via the dock plus the internal laptop panel Dock enumerates on Intel xHCI controller PCI\VEN_8086&DEV_7EC0 DisplayLink software Package 12.2.2440.0 (29 June 2026) — the current release Graphics dlidusb.inf 12.2.2412.0 (19 June 2026) Audio extension dlusbaudioext.inf 12.2.1708.0 Ethernet dlcdcncm.inf 12.2.1708.0 Previously 12.1.2684.0, which exhibited the same failure Trigger conditions Crashes occur predominantly during video conference calls (Microsoft Teams) with all three external displays active — consistent with a leak that accumulates under sustained display activity. An external Logitech c922 webcam is in use. It has already been moved off the dock onto a separate USB host controller (DEV_777D) to rule out bandwidth contention on the dock's controller. The 4 August crash occurred after that change, so contention does not appear to be a factor. Available on request WDF minidumps and heap dumps from C:\ProgramData\Microsoft\WDF\, a DisplayLink Support Tool report, and full event log exports. I can also run a trace if that would help isolate the allocation path.