Re: [PATCH] tpm: print tpm error code in hex for TPM2.0 devices

[Jerry Snitselaar]

On Fri Apr 28 17, Jarkko Sakkinen wrote:
> On Wed, Apr 26, 2017 at 03:39:54PM -0700, Jerry Snitselaar wrote:
> > For easier decoding, output the error code returned
> > from the tpm device in hex when the device is TPM2.0.
> >
> > Cc: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx>
> > Cc: Peter Huewe <peterhuewe@xxxxxx>
> > Cc: Marcel Selhorst <tpmdd@xxxxxxxxxxxx>
> > Cc: Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx>
> > Reported-by: Ken Goldman <kgoldman@xxxxxxxxxx>
> > Signed-off-by: Jerry Snitselaar <jsnitsel@xxxxxxxxxx>
> > ---
> >  drivers/char/tpm/tpm-interface.c | 11 ++++++++---
> >  1 file changed, 8 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
> > index bd2128e0b56c..b6c67eef9ae7 100644
> > --- a/drivers/char/tpm/tpm-interface.c
> > +++ b/drivers/char/tpm/tpm-interface.c
> > @@ -453,9 +453,14 @@ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, const void *buf,
> >  		return -EFAULT;
> >
> >  	err = be32_to_cpu(header->return_code);
> > -	if (err != 0 && desc)
> > -		dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
> > -			desc);
> > +	if (err != 0 && desc) {
> > +		if (chip->flags & TPM_CHIP_FLAG_TPM2)
> > +			dev_err(&chip->dev, "A TPM 2.0 error (0x%x) occurred %s\n",
> > +				err, desc);
> > +		else
> > +			dev_err(&chip->dev, "A TPM error (%d) occurred %s\n",
> > +				err, desc);
> > +	}
>
> Is there a reason for not to apply this also to TPM 1.2?
>
> /Jarkko

The 2.0 spec lists the response codes in hex, while the 1.2 spec lists them
in decimal. Maybe something like the following instead?

index 158c1db83f05..1f433d56f53c 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -526,8 +526,8 @@ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space,

       err = be32_to_cpu(header->return_code);
       if (err != 0 && desc)
-               dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
-                       desc);
+               dev_err(&chip->dev, "A TPM error (%d (0x%x)) occurred %s\n", err,
+                       err, desc);
       if (err)
               return err;


> >  	if (err)
> >  		return err;
> >
> > --
> > 2.13.0.rc0.45.ge2cb6ab84