RE: [PATCHv3] crypto: inside-secure - Fix unused variable warning when CONFIG_PCI=n

[Pascal Van Leeuwen <pvanleeuwen@verimatrix.com>]

> -----Original Message-----
> From: linux-crypto-owner@vger.kernel.org <linux-crypto-owner@vger.kernel.org> On Behalf
> Of Herbert Xu
> Sent: Friday, September 13, 2019 11:21 AM
> To: Pascal van Leeuwen <pascalvanl@gmail.com>
> Cc: linux-crypto@vger.kernel.org; antoine.tenart@bootlin.com; davem@davemloft.net;
> Pascal Van Leeuwen <pvanleeuwen@verimatrix.com>
> Subject: Re: [PATCHv3] crypto: inside-secure - Fix unused variable warning when
> CONFIG_PCI=n
> 
> On Fri, Sep 06, 2019 at 05:25:14PM +0200, Pascal van Leeuwen wrote:
> > This patch fixes an unused variable warning from the compiler when the
> > driver is being compiled without PCI support in the kernel.
> >
> > changes since v1:
> > - capture the platform_register_driver error code as well
> > - actually return the (last) error code
> > - swapped registration to do PCI first as that's just for development
> >   boards anyway, so in case both are done we want the platform error
> >   or no error at all if that passes
> > - also fixes some indentation issue in the affected code
> >
> > changes since v2:
> > - handle the situation where both CONFIG_PCI and CONFIG_OF are undefined
> >   by always returning a -EINVAL error
> > - only unregister PCI or OF if it was previously successfully registered
> >
> > Signed-off-by: Pascal van Leeuwen <pvanleeuwen@verimatrix.com>
> > ---
> >  drivers/crypto/inside-secure/safexcel.c | 35 ++++++++++++++++++++++-----------
> >  1 file changed, 24 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/crypto/inside-secure/safexcel.c b/drivers/crypto/inside-
> secure/safexcel.c
> > index e12a2a3..925c90f 100644
> > --- a/drivers/crypto/inside-secure/safexcel.c
> > +++ b/drivers/crypto/inside-secure/safexcel.c
> > @@ -1501,32 +1501,45 @@ void safexcel_pci_remove(struct pci_dev *pdev)
> >  };
> >  #endif
> >
> > -static int __init safexcel_init(void)
> > -{
> > -	int rc;
> > -
> > +/* Unfortunately, we have to resort to global variables here */
> > +#if IS_ENABLED(CONFIG_PCI)
> > +int pcireg_rc = -EINVAL; /* Default safe value */
> > +#endif
> >  #if IS_ENABLED(CONFIG_OF)
> > -		/* Register platform driver */
> > -		platform_driver_register(&crypto_safexcel);
> > +int ofreg_rc = -EINVAL; /* Default safe value */
> >  #endif
> >
> > +static int __init safexcel_init(void)
> > +{
> >  #if IS_ENABLED(CONFIG_PCI)
> > -		/* Register PCI driver */
> > -		rc = pci_register_driver(&safexcel_pci_driver);
> > +	/* Register PCI driver */
> > +	pcireg_rc = pci_register_driver(&safexcel_pci_driver);
> >  #endif
> >
> > -	return 0;
> > +#if IS_ENABLED(CONFIG_OF)
> > +	/* Register platform driver */
> > +	ofreg_rc = platform_driver_register(&crypto_safexcel);
> > +	return ofreg_rc;
> 
> If OF registration fails then you will return an error even if
> PCI registration succeeded without undoing the PCI registration.
> 
... because the _exit does not get called. Crap, did not realise that :-(
Will fix and send a PATCHv4 shortly ...

> Cheers,
> --
> Email: Herbert Xu <herbert@gondor.apana.org.au>
> Home Page: http://gondor.apana.org.au/~herbert/
> PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

Thanks,
Pascal van Leeuwen
Silicon IP Architect, Multi-Protocol Engines @ Verimatrix
www.insidesecure.com