Re: [PATCH] tpm: vtpm_proxy: Do not run tpm2_shutdown

From: Jason Gunthorpe
Date: Thu May 25 2017 - 11:51:17 EST


On Thu, May 25, 2017 at 09:12:36AM -0400, Stefan Berger wrote:
> The tpm2_shutdown does not work with the VTPM proxy driver since the
> function only gets called when the backend file descriptor is already
> closed and at this point no data can be sent anymore. A proper shutdown
> would have to be initated by a user space application, such as a container
> management stack, that sends the command via the character device before
> terminating the TPM emulator.
>
> To avoid the tpm2_shutdown we introduce a TPM_CHIP_FLAG_NO_SHUTDOWN flag
> that only the VTPM proxy driver sets. This also avoids misleading kernel
> log messages.

This seems strange to me..

Why isn't ops null if the fd has gone away?

What is the call flow that hits this?

Jason