Kernel panics on Leopard

Recently, since upgrading to OS X 10.5.3 it seems I’ve been experiencing some kernel panics, as much as once per day. After the last one I enabled kernel debug with the editing /Library/Preferences/SystemConfiguration/com.apple.Boot.plist and adding the following:

<key>Kernel Flags</key>
<string>-v debug=0x144</string> <—- ADD THIS

The -v flag is for verbose output during startup instead of the gray Apple screen. So once it kernel panicked again, it handily printed out the mac and IP address and stated it’s awaiting a remote debugger connection. On another Mac, download the 10.5.3 KernelDebugKit from ADC and fire up the debugger as follows:

gdb -arch i386 /Volumes/KernelDebugKit/mach_kernel

Then use gdb as follows:

(gdb) target remote-kdp
(gdb) attach 192.168.100.3
Connected.
(gdb) source /Volumes/KernelDebugKit/kgmacros
Loading Kernel GDB Macros package.  Type “help kgm” for more info.
(gdb) paniclog
panic(cpu 1 caller 0x002420F2): “ip_output: mix of packet in packetlist is wrong=0x577ab700″@/SourceCache/xnu/xnu-1228.5.18/bsd/netinet/ip_output.c:1494
Backtrace, Format – Frame : Return Address (4 potential args on stack)
0x5b7c7778 : 0x12b0fa (0x459294 0x5b7c77ac 0x133243 0x0)
0x5b7c77c8 : 0x2420f2 (0x475128 0x577ab700 0x0 0x0)
0x5b7c7918 : 0x24883c (0x577ab700 0x2 0x0 0x5fc9390)
0x5b7c7968 : 0x24a02b (0x2 0x0 0x0 0x1)
0x5b7c7a98 : 0x24732a (0x5fc9400 0x5b7c7c38 0x8e8544ca 0x364a8c0)
0x5b7c7c78 : 0x23bebd (0x57645f00 0x14 0xd7f47686 0x5358a4)
0x5b7c7cb8 : 0x23dc3f (0x57645f00 0x14 0x6 0x0)
0x5b7c7dd8 : 0x23dc7b (0x57645f00 0x0 0x6 0x21c5)
0x5b7c7df8 : 0x229bd3 (0x2 0x57645f00 0x5b7c7e48 0x141de3)
0x5b7c7e38 : 0x218be2 (0x2 0x57645f00 0x5b7c7e68 0x63a5fb58)
0x5b7c7ec8 : 0x215321 (0x671ae04 0x2 0x57645f00 0x3e95bc)
0x5b7c7ef8 : 0x215a7a (0x5278e4 0x5d71988 0x2 0x5b7c7f74)
0x5b7c7f68 : 0x215cd8 (0x0 0x57645f00 0x0 0x64f762c)
0x5b7c7fc8 : 0x19ebdc (0x64f7604 0x0 0x1a20b5 0x608e4f0)
Backtrace terminated-invalid frame pointer 0

BSD process name corresponding to current thread: kernel_task

Mac OS version:
9D34

Kernel version:
Darwin Kernel Version 9.3.0: Fri May 23 00:49:16 PDT 2008; root:xnu-1228.5.18~1/RELEASE_I386

I googled the output from the ip_output.c module and found several references, all indicating the Cisco VPN client’s kernel module and usually running a torrent client at the same time.

So for the moment I avoid using both at the same time and also removing the Cisco kernel modulel while not using the VPN:

[user@nefilim ~]$ sudo /System/Library/StartupItems/CiscoVPN/CiscoVPN stop
Stopping Cisco Systems VPN Driver
kextunload: unload kext /System/Library/Extensions/CiscoVPN.kext succeeded

So far so good. Sigh Cisco… won’t be the first time and certainly won’t be the last.

Resizing off screen windows in OS X (Leopard)

I run into this problem just frequent enough that I don’t remember what I did last time. Usually with Eclipse when moving back and forth between home and office (connecting to external monitor).

Here’s a whole bunch of tips. What usually does it for me is changing the doc position to the left (external monitor is on the right), zoom window and then resetting the doc back to the bottom.