Re: [tpmdd-devel] [PATCH 6/6] tpm2: add session handle context saving and restoring to the space code

From: James Bottomley
Date: Fri Feb 10 2017 - 14:12:47 EST


On Fri, 2017-02-10 at 21:10 +0200, Jarkko Sakkinen wrote:
> On Fri, Feb 10, 2017 at 08:17:11AM -0800, James Bottomley wrote:
> > On Fri, 2017-02-10 at 14:32 +0200, Jarkko Sakkinen wrote:
> > > On Wed, Feb 08, 2017 at 01:07:08PM +0200, Jarkko Sakkinen wrote:
> > > > From: James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
> > [...]
> > > > +static int tpm2_session_add(struct tpm_chip *chip, u32 handle)
> > > > +{
> > > > + struct tpm_space *space = &chip->work_space;
> > > > + int i;
> > > > +
> > > > + for (i = 0; i < ARRAY_SIZE(space->session_tbl); i++)
> > > > + if (space->session_tbl[i] == 0)
> > > > + break;
> > > > + if (i == ARRAY_SIZE(space->session_tbl)) {
> > > > + dev_err(&chip->dev, "out of session slots\n");
> > >
> > > This really should be dev_dbg.
> >
> > This was my reply to the comment the last time:
> >
> > I can do that, but I think this should be higher than debug.
> > If
> > this trips, something an application was doing will fail with a
> > non
> > TPM error and someone may wish to investigate why. Having a
> > kernel
> > message would help with that (but they won't see it if it's
> > debug).
> >
> > I'm also leaning towards the idea that we should actually have
> > one
> > more _tbl slot than we know the TPM does, so that if someone
> > goes
> > over it's the TPM that gives them a real TPM out of memory
> > error
> > rather than the space code returning -ENOMEM.
> >
> > If you agree, I think it should be four for both sessions_tbl
> > and
> > context_tbl.
> >
> > So I really don't think it should be debug. Could we compromise on
> > dev_info?
> >
> > James
>
> Oops, I'm sorry about that. I use the release chaos as an excuse :-)
> I would lower it to dev_warn().

That works. Do you want me to resend the patch?

James