April, 2013 – Graham Miln

Fixing Mac Kernel Panic: IOGMD: not wired for the IODMACommand

Since upgrading to OS X 10.8, aka Mountain Lion, my Mac Pro has been suffering from kernel panics. The solution has been to replace my two NVidia GT120 graphics cards with a single ATI 5770 graphics card.

The problem appears to effect those running multiple monitors and using the Apple issued GT120 graphics cards.

For me, the kernel panics occurred while browsing the web with Safari. Often the kernel panic occurred as I scrolled down a page. It did not require a complex web page; just a web page containing plain text was enough. It was not caused by Flash or any third party plug-in.

I reported these kernel panics to Apple through Bug Reporter, and through the “send report” mechanism upon restarting. Months have passed since the problem began, multiple updates to OS X 10.8 have been released, and still the kernel panics continued.

Rather than continue to wait for a solution from Apple, I opted to bypass the problem.

Replacing the Graphics Card

Thanks to a discussion on the Apple Discussion Forum, I learnt that replacing the graphics card will stop the kernel panics. One ATI 5770 graphics card can drive up to three monitors on a Mac Pro. I only have two monitors, so was pleased to feel the new card would not be immediately pushed to its limits.

Thus earlier this week, my replacement card arrived from Amazon. I had fun swapping out the two old cards for the slightly less dated graphics card.

Swapping over took about 30 minutes and required surprisingly little effort. The small manual included with the replacement provided all the instructions I needed.

Upon restarting everything worked. I have not had a kernel panic since and am starting to regain faith that I can use the computer for longer periods without being suddenly interrupted.

Update: I later re-introduced a single NVidia GT120 graphics card without problem.

Apple issued ATI Radeon HD 5770 graphics card
Apple issued ATI Radeon HD 5770 graphics card

Two Apple NVidia GeForce GT 120 cards removed

Mac Pro empty PCI slots ready for replacement graphics card
Mac Pro empty PCI slots ready for replacement graphics card

ATI Radeon 5770 fitted inside a Mac Pro Early 2009, 4.1 model
ATI Radeon 5770 fitted inside a Mac Pro Early 2009, 4.1 model

ATI 5770 offers two DisplayPorts and one DVI port for connecting three monitors
ATI 5770 offers two DisplayPorts and one DVI port for connecting three monitors

Kernel Panic

Below is an extract of the kernel panic reports I saw. The panics were frequent enough to change my behaviour and to avoid using Safari during critical work.

Fri Mar 29 15:44:58 2013
panic(cpu 2 caller 0xffffff800a451107): "IOGMD: not wired for the IODMACommand"@/SourceCache/xnu/xnu-2050.22.13/iokit/Kernel/IOMemoryDescriptor.cpp:1424
Backtrace (CPU 2), Frame : Return Address
0xffffff81009e30f0 : 0xffffff800a01d626 
0xffffff81009e3160 : 0xffffff800a451107 
0xffffff81009e31f0 : 0xffffff800a44bede 
0xffffff81009e32a0 : 0xffffff800a44cb0a 
0xffffff81009e32c0 : 0xffffff7f8a6dea04 
0xffffff81009e3330 : 0xffffff7f8a73f1c9 
0xffffff81009e3380 : 0xffffff7f8a73f13b 
0xffffff81009e33d0 : 0xffffff7f8a726901 
0xffffff81009e3460 : 0xffffff7f8a724ad6 
0xffffff81009e34b0 : 0xffffff7f8a70f764 
0xffffff81009e3560 : 0xffffff7f8a73c240 
0xffffff81009e3760 : 0xffffff7f8a73d983 
0xffffff81009e3830 : 0xffffff7f8b7ee480 
0xffffff81009e3970 : 0xffffff7f8b7edf6c 
0xffffff81009e3980 : 0xffffff7f8b7e4dfe 
0xffffff81009e3db0 : 0xffffff7f8b79120a 
0xffffff81009e3de0 : 0xffffff7f8b7952b3 
0xffffff81009e3e00 : 0xffffff7f8b11d2a4 
0xffffff81009e3e20 : 0xffffff7f8b11d237 
0xffffff81009e3e50 : 0xffffff7f8b7a218c 
0xffffff81009e3e80 : 0xffffff7f8b7918e2 
0xffffff81009e3ed0 : 0xffffff7f8b78f8a5 
0xffffff81009e3ef0 : 0xffffff800a4467a8 
0xffffff81009e3f30 : 0xffffff800a4452aa 
0xffffff81009e3f80 : 0xffffff800a4453d9 
0xffffff81009e3fb0 : 0xffffff800a0b2977 
      Kernel Extensions in backtrace:
         com.apple.iokit.IOSurface(86.0.4)[C1007599-42D0-32FF-9F2F-C63F4E6C1DEB]@0xffffff7f8b119000->0xffffff7f8b12afff
         com.apple.NVDAResman(8.1)[A26D2A3D-C06F-3A0F-BCFF-901A98C93C3D]@0xffffff7f8a6d9000->0xffffff7f8a9e6fff
            dependency: com.apple.iokit.IOPCIFamily(2.7.3)[1D668879-BEF8-3C58-ABFE-FAC6B3E9A292]@0xffffff7f8a644000
            dependency: com.apple.iokit.IONDRVSupport(2.3.7)[38C214C0-83C8-3594-8A4C-DC6AC3FEC163]@0xffffff7f8a6c5000
            dependency: com.apple.iokit.IOGraphicsFamily(2.3.7)[74E3E50F-E50A-3073-8C96-06F854292A91]@0xffffff7f8a682000
         com.apple.GeForce(8.1)[A15BB65E-3501-340F-87CB-2FD2BAD33E35]@0xffffff7f8b789000->0xffffff7f8b855fff
            dependency: com.apple.NVDAResman(8.1.0)[A26D2A3D-C06F-3A0F-BCFF-901A98C93C3D]@0xffffff7f8a6d9000
            dependency: com.apple.iokit.IONDRVSupport(2.3.7)[38C214C0-83C8-3594-8A4C-DC6AC3FEC163]@0xffffff7f8a6c5000
            dependency: com.apple.iokit.IOPCIFamily(2.7.3)[1D668879-BEF8-3C58-ABFE-FAC6B3E9A292]@0xffffff7f8a644000
            dependency: com.apple.iokit.IOGraphicsFamily(2.3.7)[74E3E50F-E50A-3073-8C96-06F854292A91]@0xffffff7f8a682000

BSD process name corresponding to current thread: kernel_task

Mac OS version:
12D78

Kernel version:
Darwin Kernel Version 12.3.0: Sun Jan  6 22:37:10 PST 2013; root:xnu-2050.22.13~1/RELEASE_X86_64
Kernel UUID: <div class="wp-redacted">
Kernel slide:     0x0000000009e00000
Kernel text base: 0xffffff800a000000
System model name: MacPro4,1 (Mac-F221BEC8)