x86, percpu: Fix DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED()
DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED() put percpu variables in
.page_aligned section without adding any alignment restrictions.
Currently, this doesn't cause any problem because all users of the
macros have explicit page alignment and page-sized but it's much safer
to enforce page alignment from the macros. After all, it's what they
claim to do.
Add __aligned(PAGE_SIZE) to DECLARE/DEFINE_PER_CPU_PAGE_ALIGNED() and
drop explicit alignment from it users.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h
index 68438e1..afd5f8b 100644
--- a/include/linux/percpu-defs.h
+++ b/include/linux/percpu-defs.h
@@ -69,11 +69,13 @@
/*
* Declaration/definition used for per-CPU variables that must be page aligned.
*/
-#define DECLARE_PER_CPU_PAGE_ALIGNED(type, name) \
- DECLARE_PER_CPU_SECTION(type, name, ".page_aligned")
+#define DECLARE_PER_CPU_PAGE_ALIGNED(type, name) \
+ DECLARE_PER_CPU_SECTION(type, name, ".page_aligned") \
+ __aligned(PAGE_SIZE)
#define DEFINE_PER_CPU_PAGE_ALIGNED(type, name) \
- DEFINE_PER_CPU_SECTION(type, name, ".page_aligned")
+ DEFINE_PER_CPU_SECTION(type, name, ".page_aligned") \
+ __aligned(PAGE_SIZE)
/*
* Intermodule exports for per-CPU variables.