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Last modification

• Rev 2140 2007-03-26 21:35:28
• Author: jermar

• Log message:

  Reworked handling of illegal virtual aliases caused by frame reuse.
  We moved the incomplete handling from backend's frame method to
  backend's page_fault method. The page_fault method is the one that
  can create an illegal alias if it writes the userspace frame using
  kernel address with a different page color than the page to which is
  this frame mapped in userspace. When we detect this, we do D-cache
  shootdown on all processors (!!!).
  
  If we add code that accesses userspace memory from kernel address
  space, we will have to check for illegal virtual aliases at all such
  places.
  
  I tested this on a 4-way simulated E6500 and a real-world Ultra 5,
  which has unfortunatelly only one processor.
  
  This solves ticket #26.