Merge branch 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu update from Tejun Heo:
"This includes just one patch to reject non-power-of-2 alignments and
trigger warning. Interestingly, this actually caught a bug in XEN
ARM64"
* 'for-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
percpu: ensure the requested alignment is power of two
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 01b6b46..d234cd3 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -45,6 +45,7 @@
#define REPEAT_BYTE(x) ((~0ul / 0xff) * (x))
+/* @a is a power of 2 value */
#define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
#define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask))
#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a)))
diff --git a/mm/percpu.c b/mm/percpu.c
index f696385..0686f56 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -886,7 +886,8 @@
size = ALIGN(size, 2);
- if (unlikely(!size || size > PCPU_MIN_UNIT_SIZE || align > PAGE_SIZE)) {
+ if (unlikely(!size || size > PCPU_MIN_UNIT_SIZE || align > PAGE_SIZE ||
+ !is_power_of_2(align))) {
WARN(true, "illegal size (%zu) or align (%zu) for percpu allocation\n",
size, align);
return NULL;