freebsd-nq/module
Brian Behlendorf cc9c6bcb73 Fix vdev_probe() call outside SCL_STATE_ALL lock
When an IO fails then zio_vdev_io_done() can call vdev_probe()
to determine the health of the vdev.  This is safe as long as
the original zio was submitted with zio_wait() and holds the
SCL_STATE_ALL lock over the operation.

If zio_no_wait() was used then the done callback will submit
the probe IO outside the SCL_STATE_ALL lock and hit this
ASSERT in zio_create()

  ASSERT(!vd || spa_config_held(spa, SCL_STATE_ALL, RW_READER));

Resolve the issue by only allowing vdev_probe() to be called
when there's a waiter indicating the caller is using zio_wait().
This assumes that caller is still holding SCL_STATE_ALL.

This issue isn't MMP specific but was surfaced when testing.
Without this patch it can be reproduced by running:

  zpool set multihost on <pool>
  zinject -d <vdev> -e io -T write -f 50 <pool> -L uber

Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Don Brady <don.brady@intel.com>
Closes #745
Closes #6279
2017-07-13 13:54:10 -04:00
..
avl Fix uninitialized variable in avl_add() 2016-07-25 14:21:34 -07:00
icp Clang fixes 2017-07-05 10:38:20 -07:00
nvpair OpenZFS 7812 - Remove gender specific language 2017-02-24 11:07:04 -08:00
unicode codebase style improvements for OpenZFS 6459 port 2017-01-22 13:25:40 -08:00
zcommon Multi-modifier protection (MMP) 2017-07-13 13:54:00 -04:00
zfs Fix vdev_probe() call outside SCL_STATE_ALL lock 2017-07-13 13:54:10 -04:00
zpios codebase style improvements for OpenZFS 6459 port 2017-01-22 13:25:40 -08:00
.gitignore Improve gitignore 2017-05-25 10:14:13 -07:00
Makefile.in GZIP compression offloading with QAT accelerator 2017-03-22 17:58:47 -07:00