Messages in this thread | | | Date | Mon, 29 Jan 2018 10:57:20 -0700 | From | Jason Gunthorpe <> | Subject | Re: [PATCH 1/2 v2] tpm: cmd_ready command can be issued only after granting locality |
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On Sun, Jan 28, 2018 at 09:17:53PM +0000, Winkler, Tomas wrote:
> > 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..
> > 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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