kern/45746: UVM_KMF_COLORMATCH/UVM_FLAG_COLORMATCH problems

[yamt%NetBSD.org@localhost]

>Number:         45746
>Category:       kern
>Synopsis:       UVM_KMF_COLORMATCH/UVM_FLAG_COLORMATCH problems
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Dec 27 08:45:00 +0000 2011
>Originator:     YAMAMOTO Takashi
>Release:        NetBSD current
>Organization:
        
>Environment:
        
        
>Description:
        UVM_KMF_COLORMATCH/UVM_FLAG_COLORMATCH problems

        - undocumented.

        - confusing as it abuses existing function parameters for different
          purposes.

        - it's unclear what kind of color should match with what.  pa, va, ...
          the use in uvm_pager.c imposes useless restrictions for ports where 
          aliasing is not a problem.  eg. x86.

        - it's unclear how it should interact with PMAP_PREFER.

>How-To-Repeat:
        code inspection.
>Fix:
        

>Unformatted: