On Thu, Dec 13, 2018 at 12:19:26PM +0100, Christian Zigotzky wrote: > I tried it again but I get the following error message: > > MODPOST vmlinux.o > arch/powerpc/kernel/dma-iommu.o: In function `.dma_iommu_get_required_mask': > (.text+0x274): undefined reference to `.dma_direct_get_required_mask' > make: *** [vmlinux] Error 1 Sorry, you need this one liner before all the patches posted last time: diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index d8819e3a1eb1..7e78c2798f2f 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -154,6 +154,7 @@ config PPC select CLONE_BACKWARDS select DCACHE_WORD_ACCESS if PPC64 && CPU_LITTLE_ENDIAN select DYNAMIC_FTRACE if FUNCTION_TRACER + select DMA_DIRECT_OPS select EDAC_ATOMIC_SCRUB select EDAC_SUPPORT select GENERIC_ATOMIC64 if PPC32