Diagnostic query: Unexpected kernel panic on macOS Sequoia 15.1 after waking (1794671132)

[Emily Hart]

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?

[Sarah Mitchell]

The AppleThunderboltNHI assertion strongly implicates a Thunderbolt/USB4 dock firmware incompatibility with Sequoia 15.1’s updated IOThunderboltFamily stack; validate dock firmware via the vendor’s macOS updater and inspect system_profiler SPThunderboltDataType for “Route String” errors indicating link training failures. Boot into macOS Recovery (⌘R) and run diskutil apfs list to verify snapshot integrity—corrupt com.apple.os.update-* snapshots can stall wake via kernel_task deadlocks on the APFS journal. If on Apple Silicon, force a bridgeOS restore via Apple Configurator 2 in DFU mode (right-click DFU → “Restore BridgeOS”) to reset the Thunderbolt controller’s embedded firmware, which is not updated by standard macOS installs.

iPhone 16 Pro (256GB, iOS 26) | iPad Air M2

Austin, TX | "Always try Finder Update before touching Restore."

[Liam O’Connor]

Continuity features (Handoff, Universal Control) generate IOPMrootDomain wake assertions via bluetoothd and airplayd that race with AppleThunderboltNHI port teardown during dark wake; disable “Allow Handoff between this Mac and your iCloud devices” in System Settings → General → AirDrop & Handoff and test wake stability for 48 hours. Capture a log show --predicate 'eventMessage contains "DarkWake" or eventMessage contains "Thunderbolt"' --last 24h to correlate Bluetooth LE advertisement bursts with the panic timestamp. If panics cease, re-enable features incrementally while monitoring pmset -g assertions for PreventUserIdleSystemSleep holders from coreaudiod or sharingd.

iMac 24″ M3 (16GB) | HomePod mini Stereo Pair

Dublin, IE | "Clean Wi-Fi multicast fixes half of AirPlay drops."

[Ethan Carter]

photolibraryd and bird (iCloud Drive) hold APFS snapshot references during background indexing, creating metadata contention on wake that manifests as IOPlatformPluginFamily timeouts when the storage tier (NVMe vs. Thunderbolt RAID) reports inconsistent IOService ready states. Run sudo fs_usage -w -f filesys mds_stores during a forced wake (pmset schedule wake "+1 minute") to catch snapshot mount latency spikes >500 ms. Temporarily disable “Optimize Mac Storage” in Photos → iCloud and sudo mdutil -i off / to isolate APFS snapshot enumeration as the bottleneck; if resolved, re-enable and exclude the Thunderbolt volume from Spotlight via mdutil -X /Volumes/ThunderboltVolume.

iPhone 16 Pro Max | AirPods Max USB-C

San Diego, CA | "Turn off Low Power Mode when debugging iCloud Photos stalls."

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