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MacBook Air restarting do to DCP PANIC - ASSERT error

This has suddenly started happening almost every morning when I first try to use my laptop. I have scanned for viruses (none were found), and manually shut down and restarted. I see a similar error was posted in August, with one reply that the user may need to reset the "sleep" settings, and I would like to try, but I do not see how to do that. Thanks in advance for any advice to help this situation!

The first part of the error report says:

panic(cpu 0 caller 0xfffffe0017c7ca1c): DCP PANIC - ASSERT!AppleDCPDPTXPowerController.cpp:538 No device added after powering on the rails. HPD=0 - dcpav(27)

ASSERT!AppleDCPDPTXPowerController.cpp:538 No device added after powering on the rails. HPD=0

RTKit: RTKit-2419.101.1.release - Client: local-ipad14dcp.RELEASE

!UUID: fe6311b8-1432-3071-bdc3-8a18a91b68a4

Time: 0x000001e2d092debe

This is followed by numerous additional lines of error messages:

Faulting task 27 Call Stack: 0x000000000001ea1c 0x000000000001e40c 0x000000000001e210 0x00000000000174a8 0x0000000000058218 0x00000000000fd370 0x000000000001f164 0x00000000000fd0c4 0x0000000000058110 0x0000000000107648 0x00000000000fcce8 0x000000000001ee90 0x0000000000019d54

RTKit Task List:

name | pri | stack use | status | resource | warning

0 rtk_background | 007 | 824/2048 | SEMWAIT | 0x87ce70 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x0000000000019d54

1 rtk_ep_work | 057 | 920/2048 | SEMWAIT | 0x879640 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x0000000000019d54

2 log_tx | 007 | 624/2048 | RUNNABLE | 0 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x0000000000019d54

3 log_flush | 015 | 848/4096 | SEMWAIT | 0x865490 |

0x00000000000192b8 0x000000000001a164 0x0000000000024d20 0x0000000000019d54

4 Terminator | 015 | 416/2048 | SEMWAIT | 0x860030 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x0000000000019d54

5 main | 015 | 6480/40960 | SEMWAIT | 0x84c150 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x000000000000ccd0 0x000000000000ebfc

6 dcpexpert | 015 | 240/16384 | SEMWAIT | 0x85c4c0 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x0000000000019d54

7 power | 000 | 1776/65536 | RUNNABLE | 0x636bd8 |

0x00000000000192b8 0x000000000001dc78 0x000000000001d964 0x0000000000019d54

8 AFKMailboxEndpoint | 015 | 704/16384 | SEMWAIT | 0x8578c0 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x0000000000019d54

9 rtkitpmgr | 015 | 240/16384 | SEMWAIT | 0xffffffff410fbf00 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x0000000000019d54

10 iomfb_driver | 016 | 11360/16384 | SEMWAIT | 0xffffffff410f7ed0 |

0x00000000000192b8 0x000000000001a164 0x000000000001ee24 0x0000000000019d54

MacBook Air, macOS 14.4

Posted on Oct 20, 2024 5:58 AM

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6 replies

Level 9

60,092 points

Oct 20, 2024 11:34 AM in response to bethsfromcharlotte

It is somehow related to the GPU and connected displays. It could also be due to a hub, dock, or adapter that is connected to the laptop which has a video option (or thinks it has a video option).

I guess it could also be possibly related to some third party software if you installed any with drivers to support a display.

macOS notices something that seems to be a display, but that "display" did not activate after "powering on the rails".

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Oct 20, 2024 2:25 PM in response to HWTech

Thank you for your reply. I do not have any "connected displays." I do not use a hub, dock or adapter. I have not installed any third party software recently, and certainly nothing that supports a display. I have no idea what "powering on the rails" means.

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Level 4

1,930 points

Oct 20, 2024 7:33 PM in response to HWTech

RTKit controls a bunch of the SoC co-processor comms in the M-series and used as a real time OS for cores in the SoC running auxiliary tasks like the trackpad controller, NVMe controller, etc, as well as being the real time OS for embedded Apple processors like in AirPods, Apple Pencils.

Sounds like the M-series version of an SMC reset might be in order here.

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Level 9

60,092 points

Oct 21, 2024 5:39 PM in response to bethsfromcharlotte

Disconnect all external devices to see if that makes any difference.

Run the third party app EtreCheck and post the complete report here so we can examine it for possible clues.

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Oct 21, 2024 6:02 PM in response to HWTech

Sorry if I am dense, but what external devices are you referring to? There is nothing connected to this laptop, unless you mean my wireless mouse?

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Level 9

60,092 points

Oct 21, 2024 6:08 PM in response to bethsfromcharlotte

Then you have nothing to disconnect. Post the EtreCheck report so we can review it for possible clues.

Reply

MacBook Air restarting do to DCP PANIC - ASSERT error

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