[PATCH 0/2] xfs: fix a couple xfs_buf_log_item shutdown problems

[Brian Foster <bfoster@redhat.com>]

Hi all,

This series fixes a couple filesystem shutdown corner cases related to
dealing with the xfs_buf_log_item reference count. Patch 1 fixes a
reference count leak that leads to an unmount hang due to a held buffer.
Patch 2 fixes a premature free of the bli that leads to a panic due to
use after free. Both of the above problems can be reproduced by running
generic/388 in a loop (though it may require 100-200 iterations).

I was originally considering reworking the bli reference counting, but I
don't have a clear idea on whether a cleaner solution is available atm.
These isolated fixes are lower risk and resolve the associated problems,
so should probably be considered independently regardless.

With these patches applied, generic/388 survives several thousand
iterations and otherwise no regressions are observed in my tests.
Thoughts, reviews, flames appreciated.

Brian

Brian Foster (2):
  xfs: release bli from transaction properly on fs shutdown
  xfs: remove bli from AIL before release on transaction abort

 fs/xfs/xfs_buf_item.c  | 21 ++++++++++++---------
 fs/xfs/xfs_trans_buf.c | 21 ++++++++++++++-------
 2 files changed, 26 insertions(+), 16 deletions(-)

-- 
2.7.5