Mathieu Malaterre <ma...@debian.org> writes: > Rewrite comparison since all values compared are of type `unsigned long`. > > Fix a warning (treated as error in W=1): > > CC arch/powerpc/kernel/irq.o > In file included from ./include/linux/bug.h:5:0, > from ./include/linux/cpumask.h:13, > from ./include/linux/smp.h:13, > from ./include/linux/kernel_stat.h:5, > from arch/powerpc/kernel/irq.c:35: > ./include/linux/dma-mapping.h: In function ‘dma_map_resource’: > ./arch/powerpc/include/asm/page.h:129:32: error: comparison of unsigned > expression >= 0 is always true [-Werror=type-limits] > #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < max_mapnr) > ^ > Suggested-by: Segher Boessenkool <seg...@kernel.crashing.org> > Signed-off-by: Mathieu Malaterre <ma...@debian.org> > --- > arch/powerpc/include/asm/page.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h > index 8da5d4c1cab2..19dea64e7ed2 100644 > --- a/arch/powerpc/include/asm/page.h > +++ b/arch/powerpc/include/asm/page.h > @@ -126,7 +126,8 @@ extern long long virt_phys_offset; > > #ifdef CONFIG_FLATMEM > #define ARCH_PFN_OFFSET ((unsigned long)(MEMORY_START >> > PAGE_SHIFT)) > -#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < > max_mapnr) > +#define pfn_valid(pfn) \ > + (((pfn) - ARCH_PFN_OFFSET) < (max_mapnr - ARCH_PFN_OFFSET))
I'm not a big fan of this one, because the original code is *far* more obvious as to what it's doing. I'm not sure if we can make this one a static inline, or whether that would help, but it would be worth investigating. cheers
