Re: irq-loongson-pch-pic.c:undefined reference to `of_iomap'

[Heiko Carstens <hca@linux.ibm.com>]

On Mon, Nov 16, 2020 at 10:21:26AM +0100, Arnd Bergmann wrote:
> > Don't we need the dependencies on HAS_IOMEM for the CONFIG_UML=y
> > case, too?
> 
> I would have expected that as well, but I don't see the problem when building
> an arch/um kernel, all I get is
> 
> ERROR: modpost: "devm_platform_ioremap_resource"
> [drivers/iio/adc/adi-axi-adc.ko] undefined!
> ERROR: modpost: "devm_platform_ioremap_resource"
> [drivers/ptp/ptp_ines.ko] undefined!
> ERROR: modpost: "devm_ioremap_resource"
> [drivers/net/ethernet/xilinx/xilinx_emac.ko] undefined!
> ERROR: modpost: "devm_platform_ioremap_resource_byname"
> [drivers/net/ethernet/xilinx/ll_temac.ko] undefined!
> ERROR: modpost: "devm_ioremap"
> [drivers/net/ethernet/xilinx/ll_temac.ko] undefined!
> ERROR: modpost: "devm_of_iomap"
> [drivers/net/ethernet/xilinx/ll_temac.ko] undefined!
> ERROR: modpost: "__open64_2" [fs/hostfs/hostfs.ko] undefined!
> 
> If I disable those five drivers, I can build and link a uml kernel without
> warnings. I could not find the difference compared to s390 here.
> 
> Looking a bit further, I now find that we ended up disabling CONFIG_COMPILE_TEST
> entirely for arch/um, which is clearly an option that would also work for s390.

I'll add a patch to the s390 tree which disables CONFIG_COMPILE_TEST
for s390. I wouldn't like to start again chasing/adding missing
'select' or 'depends on' statements in various config files.