cvs commit: src/sys/alpha/alpha pmap.c src/sys/amd64/amd64 pmap.c src/sys/i386/i386 pmap.c src/sys/ia64/ia64 pmap.c src/sys/powerpc/powerpc pmap.c

[Bosko Milekic]

bmilekic    2003/07/30 20:39:51 PDT

  FreeBSD src repository

  Modified files:
    sys/alpha/alpha      pmap.c 
    sys/amd64/amd64      pmap.c 
    sys/i386/i386        pmap.c 
    sys/ia64/ia64        pmap.c 
    sys/powerpc/powerpc  pmap.c 
  Log:
  Make sure that when the PV ENTRY zone is created in pmap, that it's
  created not only with UMA_ZONE_VM but also with UMA_ZONE_NOFREE.  In
  the i386 case in particular, the pmap code would hook a special
  page allocation routine that allocated from kernel_map and not kmem_map,
  and so when/if the pageout daemon drained the zones, it could actually
  push out slabs from the PV ENTRY zone but call UMA's default page_free,
  which resulted in pages allocated from kernel_map being freed to
  kmem_map; bad.  kmem_free() ignores the return value of the
  vm_map_delete and just returns.  I'm not sure what the exact
  repercussions could be, but it doesn't look good.
  
  In the PAE case on i386, we also set-up a zone in pmap, so be
  conservative for now and make that zone also ZONE_NOFREE and
  ZONE_VM.  Do this for the pmap zones for the other archs too,
  although in some cases it may not be entirely necessarily.  We'd
  rather be safe than sorry at this point.
  
  Perhaps all UMA_ZONE_VM zones should by default be also
  UMA_ZONE_NOFREE?
  
  May fix some of silby's crashes on the PV ENTRY zone.
  
  Revision  Changes    Path
  1.132     +1 -1      src/sys/alpha/alpha/pmap.c
  1.427     +1 -1      src/sys/amd64/amd64/pmap.c
  1.420     +3 -2      src/sys/i386/i386/pmap.c
  1.117     +2 -2      src/sys/ia64/ia64/pmap.c
  1.62      +2 -2      src/sys/powerpc/powerpc/pmap.c