Kernel Panics

Barney-15E, thanks for the reply. The panic log for the most recent event is posted below. If I'm looking at the right file, I didn't see anything that says "loaded kexts." Is this the correct file? If not, please give me a little more guidance. I didn't bother to reset the NVRAM since I haven't seen any of the symptoms mentioned in the article that you referenced.

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/Library/Logs/DiagnosticReports/Kernel_2018-02-26-180703_[redacted]-iMac.panic

Anonymous UUID: 610CE50D-2601-4B7F-FE2F-157E4345332F

Mon Feb 26 18:07:02 2018

*** MCA Error Report ***

CPU Machine Check Architecture Error Dump (CPU: Intel(R) Core(TM) i5-7500 CPU @ 3.40GHz, CPUID: 0x906E9)

CATERR detected! No MCA data found.

*** Device Tree ***

{

"pcie_cfg_base" : "0xe0000000",

"pci_devices" :

{

"0x0" : "MCHC@0",

"0x8000" : "PEG0@1",

"0x10000" : "IGPU@2",

"0xa0000" : "XHC1@14",

"0x100000" : "PEG0@1/IOPP/GFX0@0",

"0xb0000" : "IMEI@16",

"0x101000" : "PEG0@1/IOPP/HDAU@0,1",

"0xb8000" : "SATA@17",

"0xd8000" : "RP17@1B",

"0xe0000" : "RP01@1C",

"0xe1000" : "RP02@1C,1",

"0xfb000" : "HDEF@1F,3",

"0xe4000" : "RP05@1C,4",

"0xf8000" : "LPCB@1F",

"0xfa000" : "PMCR@1F,2",

"0x200000" : "RP17@1B/IOPP/SSD0@0",

"0xfc000" : "SBUS@1F,4",

"0x300000" : "RP01@1C/IOPP/ARPT@0",

"0x400000" : "RP02@1C,1/IOPP/GIGE@0",

"0x401000" : "RP02@1C,1/IOPP/SDXC@0,1",

"0x500000" : "RP05@1C,4/IOPP/UPSB@0",

"0x600000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB0@0",

"0x608000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB1@1",

"0x610000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB2@2",

"0x620000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB4@4",

"0x8400000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB1@1/IOPP/UPS0@0",

"0x8500000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB1@1/IOPP/UPS0@0/IOPP/pci-bridge@0",

"0x8600000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB1@1/IOPP/UPS0@0/IOPP/pci-bridge@0/IOPP/pci11c1,5 901@0",

"0x700000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB2@2/IOPP/XHC2@0",

"0x800000" : "RP05@1C,4/IOPP/UPSB@0/IOPP/DSB0@0/IOPP/NHI0@0"

},

"device_mmio" :

{

"PCI0@0" :

[

{ "a" : "0xcf8", "s" : "0x8" }

],

"PCI0@0/AppleACPIPCI/PEG0@1/IOPP/GFX0@0" :

[

{ "a" : "0x7f80000000", "s" : "0x10000000" },

{ "a" : "0x7f90000000", "s" : "0x200000" },

{ "a" : "0x92600000", "s" : "0x40000" },

{ "a" : "0x92640000", "s" : "0x20000" }

],

"PCI0@0/AppleACPIPCI/PEG0@1/IOPP/HDAU@0,1" :

[

{ "a" : "0x92660000", "s" : "0x4000" }

],

"PCI0@0/AppleACPIPCI/IGPU@2" :

[

{ "a" : "0x7f91000000", "s" : "0x1000000" },

{ "a" : "0x7fa0000000", "s" : "0x10000000" }

],

"PCI0@0/AppleACPIPCI/XHC1@14" :

[

{ "a" : "0x7f90310000", "s" : "0x10000" }

],

"PCI0@0/AppleACPIPCI/IMEI@16" :

[

{ "a" : "0x7f90324000", "s" : "0x1000" }

],

"PCI0@0/AppleACPIPCI/SATA@17" :

[

{ "a" : "0x92728000", "s" : "0x2000" },

{ "a" : "0x9272c000", "s" : "0x100" },

{ "a" : "0x9272b800", "s" : "0x800" }

],

"PCI0@0/AppleACPIPCI/RP17@1B/IOPP/SSD0@0" :

[

{ "a" : "0x92500000", "s" : "0x4000" }

],

"PCI0@0/AppleACPIPCI/RP01@1C/IOPP/ARPT@0" :

[

{ "a" : "0x92400000", "s" : "0x8000" },

{ "a" : "0x92000000", "s" : "0x400000" }

],

"PCI0@0/AppleACPIPCI/RP02@1C,1/IOPP/GIGE@0" :

[

{ "a" : "0x7f90200000", "s" : "0x10000" },

{ "a" : "0x7f90210000", "s" : "0x10000" }

],

"PCI0@0/AppleACPIPCI/RP02@1C,1/IOPP/SDXC@0,1" :

[

{ "a" : "0x7f90220000", "s" : "0x10000" }

],

"PCI0@0/AppleACPIPCI/RP05@1C,4/IOPP/UPSB@0/IOPP/DSB0@0/IOPP/NHI0@0" :

[

{ "a" : "0x92900000", "s" : "0x40000" },

{ "a" : "0x92940000", "s" : "0x1000" }

],

"PCI0@0/AppleACPIPCI/RP05@1C,4/IOPP/UPSB@0/IOPP/DSB1@1/IOPP/UPS0@0/IOPP/pci-bri dge@0/IOPP/pci11c1,5901@0" :

[

{ "a" : "0x92a00000", "s" : "0x1000" }

],

"PCI0@0/AppleACPIPCI/RP05@1C,4/IOPP/UPSB@0/IOPP/DSB2@2/IOPP/XHC2@0" :

[

{ "a" : "0x92800000", "s" : "0x10000" }

],

"PCI0@0/AppleACPIPCI/PMCR@1F,2" :

[

{ "a" : "0x92724000", "s" : "0x4000" }

],

"PCI0@0/AppleACPIPCI/HDEF@1F,3" :

[

{ "a" : "0x7f90320000", "s" : "0x4000" },

{ "a" : "0x7f90300000", "s" : "0x10000" }

],

"PCI0@0/AppleACPIPCI/SBUS@1F,4" :

[

{ "a" : "0x7f90325000", "s" : "0x100" }

],

"DMAC" :

[

{ "a" : "0x0", "s" : "0x20" },

{ "a" : "0x81", "s" : "0x11" },

{ "a" : "0x93", "s" : "0xd" },

{ "a" : "0xc0", "s" : "0x20" }

],

"FWHD" :

[

{ "a" : "0xff000000", "s" : "0x1000000" }

],

"IPIC" :

[

{ "a" : "0x20", "s" : "0x2" },

{ "a" : "0x24", "s" : "0x2" },

{ "a" : "0x28", "s" : "0x2" },

{ "a" : "0x2c", "s" : "0x2" },

{ "a" : "0x30", "s" : "0x2" },

{ "a" : "0x34", "s" : "0x2" },

{ "a" : "0x38", "s" : "0x2" },

{ "a" : "0x3c", "s" : "0x2" },

{ "a" : "0xa0", "s" : "0x2" },

{ "a" : "0xa4", "s" : "0x2" },

{ "a" : "0xa8", "s" : "0x2" },

{ "a" : "0xac", "s" : "0x2" },

{ "a" : "0xb0", "s" : "0x2" },

{ "a" : "0xb4", "s" : "0x2" },

{ "a" : "0xb8", "s" : "0x2" },

{ "a" : "0xbc", "s" : "0x2" },

{ "a" : "0x4d0", "s" : "0x2" }

],

"MATH" :

[

{ "a" : "0xf0", "s" : "0x1" }

],

"LDRC" :

[

{ "a" : "0x2e", "s" : "0x2" },

{ "a" : "0x4e", "s" : "0x2" },

{ "a" : "0x61", "s" : "0x1" },

{ "a" : "0x63", "s" : "0x1" },

{ "a" : "0x65", "s" : "0x1" },

{ "a" : "0x67", "s" : "0x1" },

{ "a" : "0x80", "s" : "0x1" },

{ "a" : "0x92", "s" : "0x1" },

{ "a" : "0xb2", "s" : "0x2" },

{ "a" : "0xffff", "s" : "0x1" },

{ "a" : "0x1800", "s" : "0xff" },

{ "a" : "0x800", "s" : "0x80" }

],

"RTC" :

[

{ "a" : "0x70", "s" : "0x8" }

],

"TIMR" :

[

{ "a" : "0x40", "s" : "0x4" },

{ "a" : "0x50", "s" : "0x4" }

],

"SMC" :

[

{ "a" : "0x300", "s" : "0x20" },

{ "a" : "0xfef00000", "s" : "0x10000" }

],

"EC" :

[

{ "a" : "0x62", "s" : "0x1" },

{ "a" : "0x66", "s" : "0x1" }

],

"PDRC" :

[

{ "a" : "0xfed10000", "s" : "0x8000" },

{ "a" : "0xfed18000", "s" : "0x1000" },

{ "a" : "0xfed19000", "s" : "0x1000" },

{ "a" : "0xe0000000", "s" : "0x10000000" },

{ "a" : "0xfd000000", "s" : "0x1800000" },

{ "a" : "0xfed20000", "s" : "0x20000" },

{ "a" : "0xfed90000", "s" : "0x4000" },

{ "a" : "0xfed45000", "s" : "0x4b000" },

{ "a" : "0xff000000", "s" : "0x1000000" },

{ "a" : "0xfee00000", "s" : "0x100000" }

]

}

}

EOF

System Profile:

Bluetooth: Version 6.0.2f2, 3 services, 27 devices, 1 incoming serial ports

Model: iMac18,3, BootROM IM183.0153.B00, 4 processors, Intel Core i5, 3.4 GHz, 8 GB, SMC 2.41f1

Thunderbolt Bus: iMac, Apple Inc., 23.1

Boot Volume File System Type: apfs

Graphics: Radeon Pro 570, Radeon Pro 570, PCIe, 4 GB

USB Device: USB 3.0 Bus

USB Device: Bluetooth USB Host Controller

USB Device: FaceTime HD Camera (Built-in)

Memory Module: BANK 0/DIMM0, 4 GB, DDR4, 2400 MHz, 0x80AD, 0x484D413835315336414652364E2D554820202020

Memory Module: BANK 1/DIMM0, 4 GB, DDR4, 2400 MHz, 0x80AD, 0x484D413835315336414652364E2D554820202020

FireWire Device: ST3500630NS Q, 1394Vender, Up to 800 Mb/sec

AirPort: spairport_wireless_card_type_airport_extreme (0x14E4, 0x16F), Broadcom BCM43xx 1.0 (7.77.37.5.1a3)

Network Service: Wi-Fi, AirPort, en1

PCI Card: pci11c1,5901, IEEE 1394 Open HCI, Thunderbolt@134,0,0

Thunderbolt Device: Thunderbolt to FireWire Adapter, Apple Inc., 1, 5.6

I wanted to update this discussion to document one other action I took before going to the Genius Bar. Some of the articles I read during troubleshooting stated that, in addition to software and internal and external hardware problems, bad/corrupt files in system caches are sometimes a problem. As a last measure before packing up my iMac and trucking it 25 miles to the Apple Store, I used OnyX to clear all the system caches. Since then, I have had no additional kernel panics. Hopefully, this has solved my problem.

Barney-15E, thanks again for your help. Your "Machine Check" response made me start thinking about system caches, since this is a brand new iMac that worked great in its first two months of life.

Thanks for the help.