1. 18 Jun, 2008 2 commits
    • Paul Mackerras's avatar
      [POWERPC] Clear sub-page HPTE present bits when demoting page size · 65ba6cdc
      Paul Mackerras authored
      
      
      When we demote a slice from 64k to 4k, and we are about to insert an
      HPTE for a 4k subpage and we notice that there is an existing 64k
      HPTE, we first invalidate that HPTE before inserting the new 4k
      subpage HPTE.  Since the bits that encode which hash bucket the old
      HPTE was in overlap with the bits that encode which of the 16 subpages
      have HPTEs, we need to clear out the subpage HPTE-present bits before
      starting to insert HPTEs for the 4k subpages.  If we don't do that, we
      can erroneously think that a subpage already has an HPTE when it
      doesn't.
      
      That in itself wouldn't be such a problem except that when we go to
      update the HPTE that we think is present on machines with a
      hypervisor, the hypervisor can tell us that the HPTE we think is there
      is actually there even though it isn't, which can lead to a process
      getting stuck in a loop, continually faulting.  The reason for the
      confusion is that the AVPN (abbreviated virtual page number) we are
      looking for in the HPTE for a 4k subpage can actually match the AVPN
      in a stale HPTE for another 64k page.  For example, the HPTE for
      the 4k subpage at 0x84000f000 will be in the same hash bucket and have
      the same AVPN as the HPTE for the 64k page at 0x8400f0000.
      
      This fixes the code to clear out the subpage HPTE-present bits.
      Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      65ba6cdc
    • Josh Boyer's avatar
      [POWERPC] 4xx: Clear new TLB cache attribute bits in Data Storage vector · b17879f7
      Josh Boyer authored
      
      
      A recent commit added support for the new 440x6 and 464 cores that have the
      added WL1, IL1I, IL1D, IL2I, and ILD2 bits for the caching attributes in the
      TLBs.  The new bits were cleared in the finish_tlb_load function, however a
      similar bit of code was missed in the DataStorage interrupt vector.
      Signed-off-by: default avatarJosh Boyer <jwboyer@linux.vnet.ibm.com>
      Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
      b17879f7
  2. 17 Jun, 2008 6 commits
  3. 16 Jun, 2008 32 commits