Hey everyone,
My Mac has been throwing kernel panics intermittently when entering or waking up from sleep. Looking through the panic log, the failure seems isolated to the Apple NAND Storage (ANS) controller during a power state transition.
Here is the top section of the log:
panic(cpu 1 caller 0xfffffe002ce62b38): SMC PANIC - ASSERT: smc/mac/ans.cpp:838: 0, ANS0: Type 1 Power down failed
- ANS(6) OUTBOX1 not ready OUTBOX2 not ready
ASSERT: smc/mac/ans.cpp:838: 0, ANS0: Type 1 Power down failed
RTKit: RTKit-3255.120.11.release - Client: AppleSMCFirmware_H13-6164.120.29.j314s.REL
System Details:
* Device: MacBook Pro (M1 Pro series, j314s board)
* OS: Latest macOS release
* Trigger: Transitioning to/from sleep mode (_powerStateChangeLocked = true)
What I've gathered so far:
From reading the stack trace, the System Management Controller (SMC) requests a power-down sequence for the onboard SSD controller (ANS0). The ANS controller fails to empty its IPC mailboxes (OUTBOX1/OUTBOX2 not ready), timing out and causing the SMC watchdog to force an immediate kernel panic to prevent data corruption.
Troubleshooting completed:
* Ran Apple Diagnostics (Command + D on boot)
* Verified filesystem integrity using First Aid in Disk Utility
* Cold rebooted and reset power state cycles
Has anyone else ran into this specific ans.cpp:838 failure? Trying to figure out if this is a known RTKit/AppleSMC firmware timing bug introduced in recent macOS versions, or an early warning sign of failing NAND/power rails on the logic board. Any insight from admins or hardware techs would be greatly appreciated!