Diagnostic query: Unexpected kernel panic on macOS Sequoia 15.1 after waking (1794700870)

[Nina Patel]

Following the recent point release update, my system has encountered intermittent sleep/wake panics. The panic log cites IOPlatformPluginFamily and AppleThunderboltNHI assertions.

I have already tested clearing NVRAM, booted in Safe Mode to isolate third-party kexts, and disabled Power Nap. Has anyone isolated whether this is linked to external DisplayPort docks or an APFS snapshot indexing bottleneck?

[Alex Tanner]

The panic signature AppleThunderboltNHI combined with IOPlatformPluginFamily strongly suggests a Thunderbolt/USB4 power state transition failure during wake, not an APFS indexing issue. Verify the dock’s firmware via system_profiler SPThunderboltDataType and compare against the vendor’s latest changelog for “S0ix/D3cold” fixes. As a hardware recovery step, disconnect all Thunderbolt devices, run sudo nvram boot-args="thunderbolt_allow_unsupported=0" to force strict enumeration, and test wake reliability on internal display only.

MacBook Air 15″ M3 (24GB) | AirPods Pro 2 USB-C

Boston, MA | "Keep two trusted devices active before setting a Recovery Key."

[Hannah Brooks]

Check pmset -g log | grep -e "Wake Requests" -e "DarkWake" -e "Kernel Client Acks" for the 30 seconds preceding the panic timestamp; look for ARPT (Wi-Fi) or XHC (USB) clients blocking the transition, which often masquerades as a Thunderbolt NHI timeout. If an external DisplayPort dock presents a USB billboard device or hub, it may be failing IOUSBHostInterface::setPowerState during the DarkWake to FullWake handoff. Disable “Wake for network access” (sudo pmset -a wom 0) and test with a direct DP-to-USB-C cable bypassing the dock’s hub controller.

MacBook Air M2 (16GB / 512GB) | iPad mini 7

Portland, OR | "Export solved community threads to PDF while they load."

[Owen Parker]

Inspect the Unified Log for AppleThunderboltNHI::handleInterrupt spikes correlated with thermalmonitord assertions using log show --predicate 'subsystem == "com.apple.iokit.IOThunderboltFamily" OR process == "thermalmonitord"' --last 1h. A faulty dock PD controller can negotiate an invalid contract (e.g., 20V/5A on a 100W port) causing the NHI to assert during the thermal pressure wake path. Run ioreg -r -c AppleThunderboltNHI | grep -i "current|voltage|power" immediately after wake to catch transient over-current flags before the watchdog fires.

iPhone 14 Pro | Apple Watch Series 10 | MagSafe Duo

Denver, CO | "Let humid USB-C ports air dry — never reach for rice."

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