[PATCH 1/2 v2] tpm: cmd_ready command can be issued only after granting locality

On Sun, Jan 28, 2018 at 09:17:53PM +0000, Winkler, Tomas wrote:

quoted

I think if a driver can fail reliquish then it needs some kind of strategy to
recover.

Maybe some driver can and some not, but if it doesn't succeed it
should return an error.

But you can't just leave the driver in some inconsistent state..

Every time I've audited something to do with 'add error codes to
destroy/free/release' I find driver design issues..

quoted

Suggest trying the reliquish again on every next request until success,
otherwise fail request locality, potentially permanently.

This is something I rather prevent because it leaves the HW in kind of undefined state 
( and we should probably work on that a bit more later).
As far as I've debugged the flow now, the driver just fails, and the error goes up 
user space caller or the internal flow is stopped.

But tranmist_command will be called again - then what does the driver
do? The driver needs an answer for that..

If you don't want to retry then I'd rather see request_locality
permanently fail then adding a return code to release.

Jason
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