build problems with powerpc allmodconfig

build problems with powerpc allmodconfig

[Christoph Hellwig]

When trying to build an allmodconfig kernel on powerpc I run into
three errors, all related to the integeration of iseries support
into the main kernel image:

 - vicocons.c can't be compiled at the same time as CONFIG_VT, but
   instead of expressing that in the Kconfig it errors out in that
   case.  This should at least be a Kconfig dependency, but long
   term viocons must work at the same time as the normal vt code
   to have a single ppc64 image
 - vioscsi linkage fails because iseries_vscsi.c and rpa_vscsi.c.
   This needs some trivial indirection via function vectors, but
   how can we find out which one to use from the driver?  Both
   seem to look the same in the device tree
 - arch/powerpc/platforms/iseries/setup.c references rd_size
   when CONFIG_INITRD is set.  But rd_size is defined drivers/block/rd.c
   which can me modular (and is selected by CONFIG_BLK_DEV_RAM).
   This same bug is repeated in the arm amd arm26 code, but except
   for those no one outside of rd.c uses this symbol.  I don't see
   a point why arch code should modify this as it's already big enough.

Re: build problems with powerpc allmodconfig

[Stephen Rothwell]

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On Tue, 31 Oct 2006 15:22:13 +0100 Christoph Hellwig <hch@lst.de> wrote:
>
>  - vicocons.c can't be compiled at the same time as CONFIG_VT, but
>    instead of expressing that in the Kconfig it errors out in that
>    case.  This should at least be a Kconfig dependency, but long
>    term viocons must work at the same time as the normal vt code
>    to have a single ppc64 image

viocons is deprecated (in favour of hvc_iseries) so we just need Kconfig
to say to build it only CONFIG_VT is not defined.

>  - vioscsi linkage fails because iseries_vscsi.c and rpa_vscsi.c.
>    This needs some trivial indirection via function vectors, but
>    how can we find out which one to use from the driver?  Both
>    seem to look the same in the device tree

The maintainer suggested that we just don't build vioscsi for iseries
if we are building the rpa version as it is not often used (in particular,
it is not used for installations).  We could, however distinguish them
by changing the "compat" field in the iSeries device tree if we wished.

>  - arch/powerpc/platforms/iseries/setup.c references rd_size
>    when CONFIG_INITRD is set.  But rd_size is defined drivers/block/rd.c
>    which can me modular (and is selected by CONFIG_BLK_DEV_RAM).
>    This same bug is repeated in the arm amd arm26 code, but except
>    for those no one outside of rd.c uses this symbol.  I don't see
>    a point why arch code should modify this as it's already big enough.

A fix for this has already been posted
(http://patchwork.ozlabs.org/linuxppc/patch?id=7523).

--
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

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Re: build problems with powerpc allmodconfig

[Stephen Rothwell]

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On Wed, 1 Nov 2006 02:22:13 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> On Tue, 31 Oct 2006 15:22:13 +0100 Christoph Hellwig <hch@lst.de> wrote:
> >
> >  - arch/powerpc/platforms/iseries/setup.c references rd_size
> >    when CONFIG_INITRD is set.  But rd_size is defined drivers/block/rd.c
> >    which can me modular (and is selected by CONFIG_BLK_DEV_RAM).
> >    This same bug is repeated in the arm amd arm26 code, but except
> >    for those no one outside of rd.c uses this symbol.  I don't see
> >    a point why arch code should modify this as it's already big enough.
>
> A fix for this has already been posted
> (http://patchwork.ozlabs.org/linuxppc/patch?id=7523).

This patch is already in the powerpc git tree.
--
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

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Re: build problems with powerpc allmodconfig

[Judith Lebzelter]

>>  - vioscsi linkage fails because iseries_vscsi.c and rpa_vscsi.c.
>>    This needs some trivial indirection via function vectors, but
>>    how can we find out which one to use from the driver?  Both
>>    seem to look the same in the device tree
>
> The maintainer suggested that we just don't build vioscsi for iseries
> if we are building the rpa version as it is not often used (in particular,
> it is not used for installations).  We could, however distinguish them
> by changing the "compat" field in the iSeries device tree if we wished.
>

How about just adding an 'ifndef' in the Makefile, as in the patch below?
This compiles ibmvscsic.o fine.

Judith Lebzelter

---
Index: linux/drivers/scsi/ibmvscsi/Makefile
===================================================================
--- linux.orig/drivers/scsi/ibmvscsi/Makefile	2006-11-06 16:52:09.000000000 -0800
+++ linux/drivers/scsi/ibmvscsi/Makefile	2006-11-07 09:35:34.019969437 -0800
@@ -1,7 +1,9 @@
 obj-$(CONFIG_SCSI_IBMVSCSI)	+= ibmvscsic.o
 
 ibmvscsic-y			+= ibmvscsi.o
+ifndef CONFIG_PPC_PSERIES
 ibmvscsic-$(CONFIG_PPC_ISERIES)	+= iseries_vscsi.o 
+endif
 ibmvscsic-$(CONFIG_PPC_PSERIES)	+= rpa_vscsi.o 
 
 obj-$(CONFIG_SCSI_IBMVSCSIS)	+= ibmvstgt.o

Re: build problems with powerpc allmodconfig

[Stephen Rothwell]

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On Tue, 7 Nov 2006 10:09:37 -0800 Judith Lebzelter <judith@osdl.org> wrote:
>
> How about just adding an 'ifndef' in the Makefile, as in the patch below?
> This compiles ibmvscsic.o fine.

Looks good.  Please resend with a comment (both for the commit and in the
Makefile) and a Signed-off-by line.

--
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au
http://www.canb.auug.org.au/~sfr/

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