From 3e352aa8ee2bd48f1a19c7742810b3a4a7ba605e Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 3 Aug 2009 14:10:11 +0900 Subject: [PATCH] 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 Cc: Ingo Molnar Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/common.c | 3 +-- include/linux/percpu-defs.h | 8 +++++--- 2 files changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c index f1961c07af9a..12493c5485e5 100644 --- a/arch/x86/kernel/cpu/common.c +++ b/arch/x86/kernel/cpu/common.c @@ -1008,8 +1008,7 @@ static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = { }; static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks - [(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]) - __aligned(PAGE_SIZE); + [(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]); /* May not be marked __init: used by software suspend */ void syscall_init(void) diff --git a/include/linux/percpu-defs.h b/include/linux/percpu-defs.h index 68438e18fff4..afd5f8b7061f 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. -- GitLab