3.5s delay between OperStatus Down and Up on NIC

NTDEV
1

Hi everyone,

I'm observing a consistent 3.5-second delay during the transition from IfOperStatusDown (2) to IfOperStatusUp (1) on a Realtek PCIe 2.5GbE Family Controller during the system boot process.

I am developing/monitoring an NDIS Filter Driver and noticed the following sequence in my logs:

  • T+3.265s: Filter driver's FilterAttach and FilterRestart handlers are called.

  • T+3.857s: The miniport reports OperStatus = 2 (Down).

  • T+7.388s: The miniport finally reports OperStatus = 1 (Up).

Log:

00:00:03.265 [NsmNF] HAttachHandler() #5 Realtek PCIe 2.5GbE...
00:00:03.265 [NsmNF] HRestartHandler() #5 Realtek PCIe 2.5GbE...
00:00:03.857 [NsmS] #5 Realtek ... OperStatus=2, AdminStatus=1
00:00:07.388 [NsmS] #5 Realtek ... OperStatus=1, AdminStatus=1

Context & Questions:

  1. Source of Delay: Is this ~3.5s gap typical for Realtek 2.5GbE NICs during hardware initialization (Auto-negotiation/PHY link-up), or could this be induced by NDIS stack serialization during boot?

  2. Filter Driver Impact: My FilterRestart completes almost immediately. Could the presence of a filter driver cause the underlying miniport to delay its media state notification, or is the miniport purely waiting for the PHY link?

  3. Internal Mechanism: Does anyone know if this specific Realtek hardware/driver waits for a specific timeout before signaling MediaConnectStateConnected to NDIS?

I want to determine if this is a "normal" hardware/link-layer characteristic or if there's something in the NDIS binding/restart sequence I should optimize.

Any insights would be greatly appreciated.

2

One way to solve this issue is to trace the calls to KeStallExecutionProcessor. I've quickly disassembled rt640x64.sys to find some device accesses are prefixed by a 30 ms delay.

Set up a kernel target, with a "touch-and-go" breakpoint when reading IAT.

ie. ba r8 rt640x64!_imp_KeStallExecutionProcessor ".printf \"us = %N\n\", @rcx; k; gc"

and the same for the rt640x64!RTDelay wrapper. The breakpoints can be improved.