macOS Catalina kernel panic on shutdown

I’m running macOS 10.15.4 and homebrew on two macs and I’m seeing kernel panic on shutdown after using either the gem command on the homebrew install ruby and at no other time during my typical day. Has anybody either seen sort of thing? Any ideas on how to debug it. Since I’m seeing this on two different machines (1 just two weeks old) I don’t believe it to be a hardware issue.

Thanks for any help.


What is segfaulting, what do brew config and brew doctor say?

Thank you for any help you can offer, really
There is more to the kernel panic report but it starts with a watchdog time out
I have already done SMC and PRAM resets on both systems to no effect

brew doctor
Your system is ready to brew.

brew config
HEAD: ca5eac845dc11e991d7d8f8c85aebb82dd454f37
Last commit: 4 hours ago
Core tap ORIGIN:
Core tap HEAD: a21474c6d88b678f51cb17db183b45ef841cbb4c
Core tap last commit: 11 minutes ago
HOMEBREW_EDITOR: /Applications/Sublime
CPU: octa-core 64-bit skylake
Homebrew Ruby: 2.6.3 => /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby
Clang: 11.0 build 1103
Git: 2.26.2 => /usr/local/bin/git
Curl: 7.64.1 => /usr/bin/curl
macOS: 10.15.5-x86_64
CLT: 1103.0.32.59
Xcode: 11.4.1

LDFLAGS=-L/usr/local/opt/ruby/lib -L/usr/local/opt/python@3.8/lib

panic(cpu 2 caller 0xffffff7f87c4faae): watchdog timeout: no checkins from watchdogd in 307 seconds (171 totalcheckins since monitoring last enabled), shutdown in progress
Backtrace (CPU 2), Frame : Return Address
0xffffff81e8febc40 : 0xffffff8006b1f5cd
0xffffff81e8febc90 : 0xffffff8006c58ac5
0xffffff81e8febcd0 : 0xffffff8006c4a67e
0xffffff81e8febd20 : 0xffffff8006ac5a40
0xffffff81e8febd40 : 0xffffff8006b1ec97
0xffffff81e8febe40 : 0xffffff8006b1f087
0xffffff81e8febe90 : 0xffffff80072c27c8
0xffffff81e8febf00 : 0xffffff7f87c4faae
0xffffff81e8febf10 : 0xffffff7f87c4f486
0xffffff81e8febf50 : 0xffffff7f87c64d9c
0xffffff81e8febfa0 : 0xffffff8006ac513e
Kernel Extensions in backtrace:[87C6D09A-72A7-3CEE-94F5-B8395E420958]@0xffffff7f87c4e000->0xffffff7f87c56fff[E93667E5-4F4F-313E-B2C2-C0DEFEBB0963]@0xffffff7f87c57000->0xffffff7f87c75fff

These links might help

This is a widely reported bug of macOS. I don’t think it’s brew related.

The only time I seem to trigger the issue is running brew related software that has opensll@1.1 as a dependent pip3, gem, etc. I was hoping that somebody would able to suggest some sort of work around

Install EtreCheck, and come back with the report. It might help isolate the issue. Review the report and remove any personal information that you don’t want included such as computer the computer’s serial number etc as it might be included in the report.

One thing you can also try, incase it is connected hardware that causes the panic is to try and reproduce the issue with no hardware connected. In other words, keep the machine to its stock out of the box hardware config.

Also, consider telling us when the issue first occurred and might it be that the issue began after any software you recently installed?

Other things - restart with the shift key (takes longer to restart) and try to reproduce the issue. Could be a kext file is provoking the reported issue.

Also, run the Apple hardware diagnostics. Start up hold D and follow the onscreen instructions.

Report back for each of these recommendations.


Could you take a look at this thread

Essentially, verify if Google Drive might be the source of the issue. Turn it off temporarily and then reproduce the issue. If the issue clears then it might be Google Drive.

Hope this helps.

Thanks for the ideas. It isn’t Google Drive I’ve never used it on either system.
EtreCheck didn’t report anything of real note. I tried the custom boot-arg watchdog=0. This doesn’t seem to help.I’ve with and without my USB hardware same results

EtreCheckPro version: 6.2.6 (6C020)
Report generated: 2020-05-25 15:01:33
Download EtreCheckPro from
Runtime: 1:51
Performance: Excellent

Problem: Other problem

Major Issues: None

Minor Issues:
These issues do not need immediate attention but they may indicate future problems or opportunities for improvement.
Unsigned files - There are unsigned software files installed. Apple has said that unsigned software will not run by default in a future version of the operating system.
Kernel boot arguments - This machine has custom kernel boot arguments.
Sharing enabled - This machine has sharing services enabled that could be a security risk.

Hardware Information:
iMac (Retina 5K, 27-inch, Late 2015)
iMac Model: iMac17,1
4 GHz Quad-Core Intel Core i7 (i7-6700K) CPU: 4-core
16 RAM - Upgradeable
BANK 0/DIMM0 - 8 GB DDR3 1867
BANK 0/DIMM1 - Empty
BANK 1/DIMM0 - 8 GB DDR3 1867
BANK 1/DIMM1 - Empty

Video Information:
AMD Radeon R9 M395X - VRAM: 4 GB
iMac (built-in) 5120 x 2880

disk0 - APPLE HDD ST2000DM001 2.00 TB (Mechanical - 7200 RPM)
Internal SATA 6 Gigabit Serial ATA
disk0s1 - EFI (MS-DOS FAT32) [EFI] 210 MB
disk0s2 [APFS Fusion Drive] 2.00 TB
disk2 [APFS Virtual drive] 2.12 TB (Shared by 5 volumes)
disk2s1 - Macintosh HD (APFS) (Shared - 10.97 GB used)
disk2s2 - Preboot (APFS) [APFS Preboot] (Shared - 99 MB used)
disk2s3 - Recovery (APFS) [Recovery] (Shared - 525 MB used)
disk2s4 - VM (APFS) [APFS VM] (Shared - 2.15 GB used)
disk2s5 - M************ Data (APFS) [APFS Virtual drive] (Shared - 100.18 GB used)

disk1 - APPLE SSD SM0128G 121.33 GB (Solid State - TRIM: Yes)
Internal PCI 8.0 GT/s x4 Serial ATA
disk1s1 - EFI (MS-DOS FAT32) [EFI] 210 MB
disk1s2 [APFS Fusion Drive] 121.12 GB
disk2 [APFS Virtual drive] 2.12 TB (Shared by 5 volumes)
disk2s1 - Macintosh HD (APFS) (Shared - 10.97 GB used)
disk2s2 - Preboot (APFS) [APFS Preboot] (Shared - 99 MB used)
disk2s3 - Recovery (APFS) [Recovery] (Shared - 525 MB used)
disk2s4 - VM (APFS) [APFS VM] (Shared - 2.15 GB used)
disk2s5 - M************ Data (APFS) [APFS Virtual drive] (Shared - 100.18 GB used)

disk3 - WD My Passport 260F 5.00 TB
External USB 5 Gbit/s USB
disk3s1 - EFI (MS-DOS FAT32) [EFI] 210 MB
disk3s2 [Core Storage Container] 5.00 TB
disk4 - T**********e (Journaled HFS+) 5.00 TB (313.59 GB used)
disk3s3 - Boot OS X (Journaled HFS+) 134 MB

Mounted Volumes:
disk2s1 - Macintosh HD
2.12 TB (Shared - 10.97 GB used, 2.02 TB available, 2.00 TB free)
Mount point: /
Read-only: Yes

disk2s4 - VM [APFS VM]
2.12 TB (Shared - 2.15 GB used, 2.00 TB free)
Mount point: /private/var/vm

disk2s5 - M************ Data [APFS Virtual drive]
2.12 TB (Shared - 100.18 GB used, 2.02 TB available, 2.00 TB free)
Mount point: /System/Volumes/Data

disk4 - Te
5.00 TB (313.59 GB used, 4.69 TB free)
Journaled HFS+
Mount point: /Volumes/T

Interface en0: Ethernet
Interface en1: Wi-Fi
802.11 a/b/g/n/ac
Interface en4: Bluetooth PAN
Interface bridge0: Thunderbolt Bridge
iCloud Quota: 3.84 GB available

Remote login: Enabled

System Software:
macOS Catalina 10.15.4 (19E287)
Time since boot: Less than an hour
Boot args: watchdog=0

System Status
Gatekeeper: App Store and identified developers
System Integrity Protection: Enabled

Antivirus software: Apple and CleanMyMac

Remote login: Enabled

Unsigned Files:
Apps: 5

System Launch Agents:
[Not Loaded] 16 Apple tasks
[Loaded] 175 Apple tasks
[Running] 122 Apple tasks

System Launch Daemons:
[Not Loaded] 33 Apple tasks
[Loaded] 189 Apple tasks
[Running] 116 Apple tasks

Launch Daemons:
[Loaded] com.macpaw.CleanMyMac4.Agent.plist (MacPaw Inc. - installed 2020-05-21)

User Launch Agents:
[Loaded] com.macpaw.CleanMyMac4.Updater.plist (MacPaw Inc. - installed 2020-05-21)
[Loaded] com.tapbots.Pastebot.PasteService.plist (Tapbots - installed 2020-05-09)

User Login Items:
[Not Loaded] CleanMyMac X Menu (MacPaw Inc. - installed 2020-05-22)
Modern Login Item
/Applications/CleanMyMac X

[Running] CleanMyMac X HealthMonitor (MacPaw Inc. - installed 2020-05-22)
Modern Login Item
/Applications/CleanMyMac X X

[Not Loaded] ColorSnapper2Helper (App Store - installed 2020-05-09)
Modern Login Item

[Not Loaded] PastebotLaunchHelper (App Store - installed 2020-05-10)
Modern Login Item

[Not Loaded] PopHubHelper (App Store - installed 2020-05-10)
Modern Login Item

[Not Loaded] Slack Login Helper (App Store - installed 2020-05-22)
Modern Login Item
/Applications/ Login

[Not Loaded] SnippetsLabLaunchd (App Store - installed 2020-05-10)
Modern Login Item

[Not Loaded] Trello Login Helper (App Store - installed 2020-05-10)
Modern Login Item
/Applications/ Login

[Loaded] cleanstart (Gary Ash - installed 2020-05-22)

Safari Extensions:
1Blocker Button (App Store - installed 2020-05-22)
Block Ads (App Store - installed 2020-05-22)
Block Adult Sites (App Store - installed 2020-05-22)
Block Annoyances (App Store - installed 2020-05-22)
Block Comments (App Store - installed 2020-05-22)
Block Social Widgets (App Store - installed 2020-05-22)
Block Trackers (App Store - installed 2020-05-22)
Custom Rules (App Store - installed 2020-05-22)
Fixerrific Extension (The Iconfactory - installed 2020-05-06)
Grammarly for Safari (App Store - installed 2020-05-21)
Read Later with Reeder (App Store - installed 2020-05-22)
Regional Rules (App Store - installed 2020-05-22)
Subscribe with Reeder (App Store - installed 2020-05-22)

Time Machine:
Auto backup: Yes
Volumes being backed up:
T**********e [Local] (Last used)
Total size: 5.00 TB
Total number of backups: 17
Oldest backup: 2020-05-11 16:36:31
Last backup: 2020-05-25 14:48:44
9 local snapshots
Oldest local snapshot: 2020-05-24 14:42:41
Last local snapshot: 2020-05-25 14:17:41

System Load: 1.32 (1 min ago) 1.36 (5 min ago) 1.61 (15 min ago)
Nominal I/O speed: 0.62 MB/s
File system: 13.39 seconds
Write speed: 566 MB/s
Read speed: 1357 MB/s

CPU Usage Snapshot:
Type Overall
System: 1 %
User: 1 %
Idle: 98 %

Top Processes Snapshot by CPU:
Process (count) CPU (Source - Location)
EtreCheckPro 4.88 % (Etresoft, Inc.)
WindowServer 3.62 % (Apple)
deleted 2.32 % (Apple)
kernel_task 1.68 % (Apple)
Twitter 1.04 % (App Store)

Top Processes Snapshot by Memory:
Process (count) RAM usage (Source - Location)
EtreCheckPro 496 MB (Etresoft, Inc.)
mds_stores 300 MB (Apple)
NotificationCenter 241 MB (Apple)
Dash 212 MB (Bogdan Popescu)
Twitter 209 MB (App Store)

Top Processes Snapshot by Network Use:
Process (count) Input / Output (Source - Location)
Twitter 689 KB / 2 MB (App Store)
mDNSResponder 1 MB / 161 KB (Apple)
ath 199 KB / 228 KB (Apple)
usbmuxd 96 KB / 73 KB (Apple)
cloudd 56 KB / 23 KB (Apple)

Top Processes Snapshot by Energy Use:
Process (count) Energy (0-100) (Source - Location)
SnippetsLab 2 (App Store)
WindowServer 2 (Apple)
CleanMyMac X 0 (MacPaw Inc.)
Magnet 0 (App Store)
Keyboard Maestro Engine 0 (Stairways Software Pty Ltd)

Virtual Memory Information:
Physical RAM: 16 GB

Free RAM: 5.54 GB
Used RAM: 5.99 GB
Cached files: 4.47 GB

Available RAM: 10.01 GB
Swap Used: 0 B

Software Installs (past 30 days):
Install Date Name (Version)
2020-05-09 Gatekeeper Configuration Data (181)
2020-05-09 Numbers (10.0)
2020-05-09 Keynote (10.0)
2020-05-09 Pages (10.0)
2020-05-09 PCalc (4.7)
2020-05-09 The Unarchiver (4.2.1)
2020-05-09 Kindle (1.28.0)
2020-05-09 AS Timer (5.1)
2020-05-09 RegExRX (1.9.2)
2020-05-09 PopHub (2.1.4)
2020-05-09 Final Cut Pro X (10.4.8)
2020-05-09 VideoConverterUltimate (11.5.1)
2020-05-09 Pro Video Formats (2.1.1)
2020-05-09 Final Cut Pro X Supplemental Content (1.0)
2020-05-09 Trello (2.11.5)
2020-05-09 ColorSnapper2 (1.5.1)
2020-05-09 Magnet (2.4.5)
2020-05-09 Image2icon (2.11)
2020-05-09 Kaleidoscope (2.3.2)
2020-05-09 Pastebot (2.3)
2020-05-09 Turtle Beach Audio Hub (2.7.5)
2020-05-09 Highland 2 (2.8.1)
2020-05-09 Cyberduck (7.3.1)
2020-05-09 SnippetsLab (1.9.2)
2020-05-09 Transporter (1134)
2020-05-09 Marked 2 (2.5.40)
2020-05-21 XProtectPlistConfigData (2121)
2020-05-21 MRTConfigData (1.60)
2020-05-21 Command Line Tools for Xcode (11.5)
2020-05-21 Slack (4.6.0)
2020-05-21 Grammarly for Safari (9.17)
2020-05-21 Twitter (8.19)
2020-05-21 1Blocker (3.6)
2020-05-21 Logic Pro X (10.5.0)
2020-05-21 Reeder (4.2.4)
2020-05-21 EFICheck AllowListAll (89)
2020-05-21 Pixelmator Pro (1.6.3)
2020-05-21 Zoom (5.0.24978.0517)
2020-05-22 Xcode (11.5)

Diagnostics Information (past 7-30 days):

End of report

Not a solution - but just chiming in to report that I was also seeing this kernel panic (watchdog timeout) on 2 Macs running 10.15.5. I installed the supplemental update yesterday to 19F101 and fingers crossed I haven’t seen it since. Too soon to tell, but have you updated, or had this panic since updating?

Unfortunately I have

This is still present in Big Sur beta 7.

I have the issue on two 16inch MBPs.

Cannot believe they don’t fix such a fundamental issue which is regularly blocking the computer shutting down gracefully. How bizarre.

Really sad to hear that @john_alan. I am also still regularly getting this hang on reboot on my 2 Macs running 10.15.6 (19G2021).

Was really hoping the major upgrade to 11.0 would clear out whatever cobweb was causing this. :disappointed:

1 Like

my system seems to be working better. i haven’t knowingly done anything to try to fix the issue lately so it maybe was a bad software combo

I plan to do a clean drive install on Big Sur once it’s released. I don’t have time or courage enough for the betas

1 Like

I’m also having this issue during shutdown on both Catalina and Big Sur with my 2017 15"

Are you using a thunderbolt dock? I was wondering if it was related.

@stanislas I have the issue on 2 Macs both running 10.15.7, no TB dock on either. So I’d say no, probably not related. Also don’t think this is a 3rd party kext because my MacBook Air has exactly Zero non-Apple kexts loaded and still suffers this issue.

I’ve just gotten used to the idea that rebooting my Mac is a 10-minute ordeal. I’ve submitted the crash dump that comes up after every boot too many times to count, but I assume it all goes to /dev/null at Apple while they polish iOS and continue to dumb down everything else.

I’ve found this answer on stack exchange helpful.
TL;DR try resetting SMC.