MacBook Pro crashes and panic after Yosemite
There is a thread on the Apple forum, with a possible solution:


  
  Go to "Activity Monitor" - you should see launchd using lots of CPU resources - and I think this is why it's crashing intermittently.  The Mac is going nuts trying to launch something which it can't and it finally resets itself.
  Go to "Console" and look up System Log Queries - All Messages - it's going to be pretty obvious what launchd is trying to er, launch.  On my computer it was trying to launch this: /Library/eBookLibrary/eBook Library Launcher.app/Contents/MacOS/eBook Library Launcher
  Go to /Library/LaunchAgents - you will see the plist file that the launchd is trying to launch - in my case it was the Sony ebook reader plist.  I deleted it without any problems.
  Restart the system.
  Go back to "Activity Monitor" - you should no longer see launchd hogging the resources.
  


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