From: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> Commit badbda53e505089062e194c614e6f23450bc98b2 upstream. pageblock_order can be (at least) an unsigned int or an unsigned long depending on the kernel config and architecture, so use max_t(unsigned long, ...) when comparing it. fixes these warnings: In file included from include/asm-generic/bug.h:13:0, from arch/powerpc/include/asm/bug.h:127, from include/linux/bug.h:4, from include/linux/mmdebug.h:4, from include/linux/mm.h:8, from include/linux/memblock.h:18, from mm/cma.c:28: mm/cma.c: In function 'cma_init_reserved_mem': include/linux/kernel.h:748:17: warning: comparison of distinct pointer types lacks a cast (void) (&_max1 == &_max2); ^ mm/cma.c:186:27: note: in expansion of macro 'max' alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); ^ mm/cma.c: In function 'cma_declare_contiguous': include/linux/kernel.h:748:17: warning: comparison of distinct pointer types lacks a cast (void) (&_max1 == &_max2); ^ include/linux/kernel.h:747:9: note: in definition of macro 'max' typeof(y) _max2 = (y); ^ mm/cma.c:270:29: note: in expansion of macro 'max' (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order)); ^ include/linux/kernel.h:748:17: warning: comparison of distinct pointer types lacks a cast (void) (&_max1 == &_max2); ^ include/linux/kernel.h:747:21: note: in definition of macro 'max' typeof(y) _max2 = (y); ^ mm/cma.c:270:29: note: in expansion of macro 'max' (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order)); ^ [akpm@xxxxxxxxxxxxxxxxxxxx: coding-style fixes] Link: http://lkml.kernel.org/r/20160526150748.5be38a4f@xxxxxxxxxxxxxxxx Signed-off-by: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- mm/cma.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/cma.c b/mm/cma.c index 8e9ec13d31db..0f4549cf796f 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -168,7 +168,8 @@ int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, return -EINVAL; /* ensure minimal alignment requied by mm core */ - alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); + alignment = PAGE_SIZE << + max_t(unsigned long, MAX_ORDER - 1, pageblock_order); /* alignment should be aligned with order_per_bit */ if (!IS_ALIGNED(alignment >> PAGE_SHIFT, 1 << order_per_bit)) @@ -250,8 +251,8 @@ int __init cma_declare_contiguous(phys_addr_t base, * migratetype page by page allocator's buddy algorithm. In the case, * you couldn't get a contiguous memory, which is not what we want. */ - alignment = max(alignment, - (phys_addr_t)PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order)); + alignment = max(alignment, (phys_addr_t)PAGE_SIZE << + max_t(unsigned long, MAX_ORDER - 1, pageblock_order)); base = ALIGN(base, alignment); size = ALIGN(size, alignment); limit &= ~(alignment - 1); -- 2.9.0