[ 066/108] MIPS: Properly align the .data..init_task section.

Ben Hutchings
2012-07-23T01:43:19Z

From: David Daney <david.daney@cavium.com>

commit 7b1c0d26a8e272787f0f9fcc5f3e8531df3b3409 upstream.

Improper alignment can lead to unbootable systems and/or random
crashes.

[ralf@linux-mips.org: This is a lond standing bug since
6eb10bc9e2deab06630261cd05c4cb1e9a60e980 (kernel.org) rsp.
c422a10917f75fd19fa7fe070aaaa23e384dae6f (lmo) [MIPS: Clean up linker script
using new linker script macros.] so dates back to 2.6.32.]

Signed-off-by: David Daney <david.daney@cavium.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3881/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
arch/mips/include/asm/thread_info.h | 4 ++--
arch/mips/kernel/vmlinux.lds.S | 3 ++-
2 files changed, 4 insertions(+), 3 deletions(-)

--- a/arch/mips/include/asm/thread_info.h
+++ b/arch/mips/include/asm/thread_info.h
@@ -60,6 +60,8 @@ struct thread_info {
register struct thread_info *__current_thread_info __asm__("$28");
#define current_thread_info() __current_thread_info

+#endif /* !__ASSEMBLY__ */
+
/* thread information allocation */
#if defined(CONFIG_PAGE_SIZE_4KB) && defined(CONFIG_32BIT)
#define THREAD_SIZE_ORDER (1)
@@ -97,8 +99,6 @@ register struct thread_info *__current_t

#define free_thread_info(info) kfree(info)

-#endif /* !__ASSEMBLY__ */
-
#define PREEMPT_ACTIVE 0x10000000

/*
--- a/arch/mips/kernel/vmlinux.lds.S
+++ b/arch/mips/kernel/vmlinux.lds.S
@@ -1,5 +1,6 @@
#include <asm/asm-offsets.h>
#include <asm/page.h>
+#include <asm/thread_info.h>
#include <asm-generic/vmlinux.lds.h>

#undef mips
@@ -73,7 +74,7 @@ SECTIONS
.data : { /* Data */
. = . + DATAOFFSET; /* for CONFIG_MAPPED_KERNEL */

- INIT_TASK_DATA(PAGE_SIZE)
+ INIT_TASK_DATA(THREAD_SIZE)
NOSAVE_DATA
CACHELINE_ALIGNED_DATA(1 << CONFIG_MIPS_L1_CACHE_SHIFT)
READ_MOSTLY_DATA(1 << CONFIG_MIPS_L1_CACHE_SHIFT)