Re: [PATCH] tpm: fix invalid constant expressions in tpm.h

From: Jarkko Sakkinen
Date: Tue Aug 30 2016 - 02:31:41 EST


On Mon, Aug 29, 2016 at 09:45:36PM -0600, Jason Gunthorpe wrote:
> On Tue, Aug 30, 2016 at 04:28:17AM +0300, Jarkko Sakkinen wrote:
> > The enums tpm_capabilities and tpm_sub_capabilities do not contain legit
> > constant expressions. This commit makes cap_id a separate parameter
> > in
>
> I wonder if this is a bug in sparse? the macro uses gcc magic to
> expand to a constexpr.
>
> You could also use __constant_cpu_to_be32 and similar instead.
>
> But I admit I never liked the use of no-host endian in the constants..

It's too much magic for me, be it way or another :)


> > #define TPM_ORD_STARTUP cpu_to_be32(153)
> > #define TPM_ST_CLEAR cpu_to_be16(1)
>
> Would be nice to see these fixed into an enum someday too

(putting note into my backlog text file)

> > +enum tpm1_capabilities {
> > + TPM1_CAP_FLAG = 0x04,
> > + TPM1_CAP_PROP = 0x05,
> > + TPM1_CAP_VERSION_1_1 = 0x06,
> > + TPM1_CAP_VERSION_1_2 = 0x1A,
>
> I usually discourage the extra horizontal whitespace, just causes patch churn to
> keep it up (and clang-format won't do it automatically). Not sure if
> there is a consensus on that though.
>
> But looks fine to me.
>
> Reviewed-by: Jason Gunthorpe <jgunthorpe@xxxxxxxxxxxxxxxxxxxx>

Thanks!

> Jason

/Jarkko