linux-kernel - Re: [PATCH] tpm: fix unused-value issues in tpm_try

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Message-ID: <20181011120140.GA15767@linux.intel.com>
Date:   Thu, 11 Oct 2018 15:01:40 +0300
From:   Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>
To:     Jason Gunthorpe <jgg@...pe.ca>
Cc:     "Gustavo A. R. Silva" <gustavo@...eddedor.com>,
        Tomas Winkler <tomas.winkler@...el.com>,
        Peter Huewe <peterhuewe@....de>, Arnd Bergmann <arnd@...db.de>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-integrity@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] tpm: fix unused-value issues in tpm_try_transmit

On Wed, Oct 10, 2018 at 08:06:38AM -0600, Jason Gunthorpe wrote:
> On Wed, Oct 10, 2018 at 03:38:17PM +0200, Gustavo A. R. Silva wrote:
> > Currently, there are some values assigned to variable *rc*, which
> > are never actually used in any computation, because such variable
> > is updated at line 550, before they can be used:
> > 
> > 549out:
> > 550        rc = tpm_go_idle(chip, flags);
> > 551        if (rc)
> > 552                goto out;
> > 
> > Fix this by removing such assignments. 
> 
> Should this be done by not quashing rc during the error unwind rather
> than dropping the errors?

Yeah.`

Wondering if tpm_go_idle() should simply be a void-function i.e. issue
just a warning inside (disclaimer: did not revisit its code when writing
this).

> Jason

/Jarkko