Re: [PATCH] tpm: Fix TPM 1.2 Shutdown sequence to prevent future TPM operations

Jason Gunthorpe
2019-07-11T19:46:29Z

On Thu, Jul 11, 2019 at 10:43:13PM +0300, Jarkko Sakkinen wrote:
> On Thu, Jul 11, 2019 at 09:35:33PM +0300, Jarkko Sakkinen wrote:
> > > Careful with this, you can't backport this to any kernels that don't
> > > have the sysfs ops locking changes or they will crash in sysfs code.
> >
> > Oops, I was way too fast! Thanks Jason.
>
> Hmm... hold on a second.
>
> How would the crash realize? I mean this is at the point when user space
> should not be active.

Not strictly, AFAIK

> Secondly, why the crash would not realize with
> TPM2? The only thing the fix is doing is to do the same thing with TPM1
> essentially.

TPM2 doesn't use the unlocked sysfs path

Jason