Re: [2.6 patch] SCSI_AIC94XX must depend on SCSI

[Sam Ravnborg <sam@ravnborg.org>]

On Thu, Mar 06, 2008 at 03:32:06PM -0600, James Bottomley wrote:
> On Thu, 2008-03-06 at 12:35 -0800, Darrick J. Wong wrote:
> > On Thu, Mar 06, 2008 at 10:22:46PM +0200, Adrian Bunk wrote:
> > > This patch fixes the following build error reported by Toralf Förster:
> > > 
> > > <--  snip  -->
> > > 
> > > ...
> > >   MODPOST 243 modules
> > > ERROR: "sas_bios_param" [drivers/scsi/mvsas.ko] undefined!
> > 
> > <snip>
> > 
> > > --- a/drivers/scsi/aic94xx/Kconfig
> > > +++ b/drivers/scsi/aic94xx/Kconfig
> > 
> > Maybe I'm missing something here, but how does patching aic94xx Kconfig
> > fix an mvsas build problem?
> 
> Actually, it's a dependency chain fault.  The config this was generated
> from has
> 
> CONFIG_SCSI=m
> 
> CONFIG_SCSI_AIC94XX=y
> 
> the latter then forces
> 
> CONFIG_SCSI_SAS_LIBSAS=y
> 
> I think the error reported is wrong: the kernel just should have failed
> to link, since both the built in aic94xx and libsas have scsi
> dependencies.
> 
> We have a few other drivers in this category (like ibmvscsi).  The root
> cause seems to be that SCSI_LOWLEVEL doesn't act as a tristate.  I think
> a fix that will prevent all of these issues from recurring is this one.

Until kconfig is fixed - never select a symbol with a prompt or dependencies.
Then most issues are gone.

	Sam