1. 01 Mar, 2016 2 commits
  2. 29 Feb, 2016 1 commit
    • Neil Horman's avatar
      3c59x: mask LAST_FRAG bit from length field in ring · a6522c08
      Neil Horman authored
      Recently, I fixed a bug in 3c59x:
      
      commit 6e144419
      Author: Neil Horman <nhorman@tuxdriver.com>
      Date:   Wed Jan 13 12:43:54 2016 -0500
      
          3c59x: fix another page map/single unmap imbalance
      
      Which correctly rebalanced dma mapping and unmapping types.  Unfortunately it
      introduced a new bug which causes oopses on older systems.
      
      When mapping dma regions, the last entry for a packet in the 3c59x tx ring
      encodes a LAST_FRAG bit, which is encoded as the high order bit of the buffers
      length field.  When it is unmapped the LAST_FRAG bit is cleared prior to being
      passed to the unmap function.  Unfortunately the commit above fails to do that
      masking.  It was missed in testing because the system on which I tested it had
      an intel iommu, the driver for which ignores the size field, using only the DMA
      address as the token to identify the mapping to be released.  However, on older
      systems that rely on swiotlb (or other dma drivers that key off that length
      field), not masking off that LAST_FRAG high order bit results in parsing a huge
      size to be release, leading to all sorts of odd corruptions and the like.
      
      Fix is easy, just mask the length with 0xFFF.  It should really be
      &(LAST_FRAG-1), but 0xFFF is the style of the file, and I'd like to make this
      fix minimal and correct before making it prettier.
      
      Appies to the net tree cleanly.  All testing on both iommu and swiommu based
      systems produce good results
      Signed-off-by: default avatarNeil Horman <nhorman@tuxdriver.com>
      CC: Steffen Klassert <klassert@mathematik.tu-chemnitz.de>
      CC: "David S. Miller" <davem@davemloft.net>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a6522c08
  3. 26 Feb, 2016 2 commits
  4. 25 Feb, 2016 7 commits
  5. 24 Feb, 2016 6 commits
  6. 23 Feb, 2016 5 commits
  7. 22 Feb, 2016 17 commits