K 10
svn:author
V 6
scottl
K 8
svn:date
V 27
2014-06-30T01:01:54.408317Z
K 7
svn:log
V 598
In rare cases, a SATA drive can stop responding to commands and trigger a
reset device task request from the driver.  If the drive fails to respond
with a signature FIS, the driver would previously get into an endless retry
loop, stalling all I/O to the drive and keeping user processes stranded.
Instead, fail the i/o and invalidate the device if the task management
command times out.  This is controllable with the sysctl and tunable
hw.isci.fail_on_task_timeout
dev.isci.0.fail_on_task_timeout

The default for these is 1.

Reviewed by:	jimharris
Obtained from:	Netflix, Inc.
MFC after:	2 days

END