Re: [PATCH] tpm: fix crash in tpm_tis deinitialization

[Jarkko Sakkinen]

On Wed, Apr 13, 2016 at 09:16:51AM +0300, Jarkko Sakkinen wrote:
> On Tue, Apr 12, 2016 at 11:26:55AM -0600, Jason Gunthorpe wrote:
> > On Tue, Apr 12, 2016 at 07:26:27AM +0300, Jarkko Sakkinen wrote:
> > > > This needs to be after ops is fenced, something like this.
> > > 
> > > I would appreciate a supporting argument.
> > > 
> > > I guess the argument here is that this will prevent user space from
> > > issuing TPM commands after the shutdown command has been sent?
> > 
> > It prevents everything including the kernel from issuing a command
>                          ^^^^^^^^^^^^^^^^^^^^
> 
> That lock is not used to exclude kernel access. Read lock is only taken
> for the user space device in tpm-dev.c.

My bad. For the in-kernel API it is taken through tpm_find_get().

I'll update the fix.

/Jarkko