git: DragonFly_RELEASE_3_0 kernel - Fix another AHCI bug

Matthew Dillon dillon at
Thu Mar 29 16:07:34 PDT 2012

commit 7e6c59b8a3ec917894cf3256b092e3f7dcc2891b
Author: Matthew Dillon <dillon at>
Date:   Fri Mar 23 01:47:48 2012 -0700

    kernel - Fix another AHCI bug
    * Remove the unlock/lock sequences around the xpt_done() calls.  These
      temporary unlocks create a gap which can allow another interrupt to
      squeeze in and interfere with the interrupt thread that is already
      running, resulting in corruption.
      This bug occurs under very heavy loads, and typically required multiple
      concurrent ops to a SSD to trigger.
    * Add additional assertions to catch issues and reorder one of the
    * This is a bit non-optimal, be on the lookout for deadlocks in case it
      turns out that holding the lock is a bad idea.

Summary of changes:
 sys/dev/disk/ahci/ahci.c           |   51 +++++++++--------------------------
 sys/dev/disk/ahci/ahci_cam.c       |   24 ++++++++++++----
 sys/dev/disk/ahci/ahci_dragonfly.c |    2 +-
 3 files changed, 32 insertions(+), 45 deletions(-)

DragonFly BSD source repository

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