1. 18 Aug, 2014 1 commit
    • NeilBrown's avatar
      md/raid5: avoid livelock caused by non-aligned writes. · a40687ff
      NeilBrown authored
      If a stripe in a raid6 array received a write to each data block while
      the array is degraded, and if any of these writes to a missing device
      are not page-aligned, then a live-lock happens.
      
      In this case the P and Q blocks need to be read so that the part of
      the missing block which is *not* being updated by the write can be
      constructed.  Due to a logic error, these blocks are not loaded, so
      the update cannot proceed and the stripe is 'handled' repeatedly in an
      infinite loop.
      
      This bug is unlikely as most writes are page aligned.  However as it
      can lead to a livelock it is suitable for -stable.  It was introduced
      in 3.16.
      
      Cc: stable@vger.kernel.org (v3.16)
      Fixed: 67f45548Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      a40687ff
  2. 16 Aug, 2014 39 commits