[RESEND RFC PATCH 1/1] linux/mm.h: canonicalize macro PAGE_ALIGNED() definition

From: zijun_hu
Date: Tue Sep 27 2016 - 08:50:41 EST


From: zijun_hu <zijun_hu@xxxxxxx>

macro PAGE_ALIGNED() is prone to cause error because it doesn't follow
convention to parenthesize parameter @addr within macro body, for example
unsigned long *ptr = kmalloc(...); PAGE_ALIGNED(ptr + 16);
for the left parameter of macro IS_ALIGNED(), (unsigned long)(ptr + 16)
is desired but the actual one is (unsigned long)ptr + 16

it is fixed by simply canonicalizing macro PAGE_ALIGNED() definition

Signed-off-by: zijun_hu <zijun_hu@xxxxxxx>
---
include/linux/mm.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index ef815b9cd426..ec6818631635 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -126,7 +126,7 @@ extern int overcommit_kbytes_handler(struct ctl_table *, int, void __user *,
#define PAGE_ALIGN(addr) ALIGN(addr, PAGE_SIZE)

/* test whether an address (unsigned long or pointer) is aligned to PAGE_SIZE */
-#define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)addr, PAGE_SIZE)
+#define PAGE_ALIGNED(addr) IS_ALIGNED((unsigned long)(addr), PAGE_SIZE)

/*
* Linux kernel virtual memory manager primitives.
--
1.9.1