From: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx> Hi Vindo, This small series fixes the build error and warnings for ia64 and m32r which kbuild test robot found and where introduced in the series '[PATCHv9 0/6] dmaengine: rcar-dmac: add iommu support for slave transfers'. It is based ontop of: git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/slave-dma.git next The fixes are only compile tested for the ia64 and m32r architecture to show that the error and warnings are fixed. It is tested on ARM to prove that the intended functionality still works. Kbuild test robot found one more class of warnings for the patch series mentioned above for the balackfin arch. include/linux/dma-mapping.h: In function 'dma_map_resource': >> include/asm-generic/page.h:90:32: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr) ^ These warnings are not addressed in this series since they are not new or unique to original patch. They come from how pfn_valid() is implemented in include/asm-generic/page.h, if ARCH_PFN_OFFSET is 0 the warning is triggered. On the kbuild blackfin build it is defined as '(0x0 >> 12)' so any invocation of pfn_valid() will trigger it. I tried to fix it but was unable to find a good solution. There is a MIPS specific fix for this in commit 95486e4 (MIPS: Fix flood of warnings about comparsion being always true.), but a similar fix for asm-generic seems to tricky for me to attempt since the macro needs to be turned into a static inline function and that might be harmful. I also toyed with the solution of '#if ARCH_PFN_OFFSET == 0' to provided an alternative pfn_valid() macro, but since ARCH_PFN_OFFSET is defined as an expression and not a constant that wont work. If you can think of another way I be happy to try that out and see if I can make it work. Niklas Söderlund (2): dma-mapping: fix ia64 build, use PHYS_PFN dma-mapping: fix m32r build warning include/linux/dma-mapping.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) -- 2.9.3 -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html