Re: [PATCH][RFC] scsi_transport_fc: Implement I_T nexus reset

[Mike Christie <michaelc@cs.wisc.edu>]

On 12/07/2012 03:05 PM, Jeremy Linton wrote:
> On 12/7/2012 1:58 PM, Chad Dupuis wrote:
>> Also, are there certain port types we wouldn't want to send this reset to 
>> such as tape?
> 
> 	AFAIK, for tape it shouldn't cause any more harm than the target reset which
> happens immediately before it. This patch is infinitely better than the
> previous "bus" reset behavior.
> 
> 	That said, its far from perfect. The code (as I understand it) isn't
> differentiating between isolating the failure, or bringing out the big
> hammer in an attempt to correct problems on a specific I_T_L. If you
> drop/reset the I_T because one of the LUN's is misbehaving before verifying
> the status of other LUN's on the target, you risk interrupting operations to
> functional devices.
> 

When this code is called the scsi eh has run the abort handler for each
outstanding command and that has failed, and it has run the lun/device
reset handler and that has failed (or the eh operations succeeded but
the TUR checkup the scsi eh does failed).