On Mon, Feb 04 2008 at 20:32 +0200, "Salyzyn, Mark" <[EMAIL PROTECTED]> wrote:
> ACK with condition that community accepts the RFC's entire premise.
> 
> The removed code that shunted the REQUEST_SENSE was based on the assumption 
> that the sense data in the current scsi command packet was left over from the 
> previous command's execution with a check condition as the scsi command 
> packet 
> is reused to issue the REQUEST_SENSE. For a new, or second from the target's 
> point 
> of view, request sense to the target issued by these older kernels would 
> always 
> return an erased sense. The dpt_i2o driver does not itself maintain the sense 
> history, 
> nor does the Firmware. This behavior, I believe, is not the case for current 
> kernels so 
> the code fragment made little sense (pun not intended). If my historical 
> knowledge is 
> correct, this (now removed) workaround makes no more sense because the scsi 
> layer correctly 
> manages adapters that produce auto-request sense and does not ever turn 
> around the command 
> and send a second request for sense information.

> Given this understanding, I have no problem with the removed fragment of 
> REQUEST_SENSE shunting. 
> However, I do urge some target error recovery testing, tape drives being the 
> likely type of target 
> affected by this change. I have no such hardware to confirm...
> Sincerely -- Mark Salyzyn

I have removed this test because the midlayer does a scsi_eh_reset_sense() just 
before
the new invocation of a command. So even if the second bad REQUEST_SENSE comes 
this
will not filter it out anymore. If such a thing still happens? A driver state 
machine
must be used to filter it out, or of course midlayer should be fixed.

Boaz
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