[PATCH v2 12/20] kexec: allocate vmcoreinfo note buffer on page-size boundary

HATAYAMA Daisuke
2013-03-05T07:06:04Z

To satisfy mmap()'s page-size boundary requirement, specify aligned
attribute to vmcoreinfo_note objects to allocate it on page-size
boundary.

Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
---

include/linux/kexec.h | 6 ++++--
kernel/kexec.c | 2 +-
2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index d2e6927..5113570 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -185,8 +185,10 @@ extern struct kimage *kexec_crash_image;
#define VMCOREINFO_BYTES (4096)
#define VMCOREINFO_NOTE_NAME "VMCOREINFO"
#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
-#define VMCOREINFO_NOTE_SIZE (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
- + VMCOREINFO_NOTE_NAME_BYTES)
+#define VMCOREINFO_NOTE_SIZE ALIGN(KEXEC_NOTE_HEAD_BYTES*2 \
+ +VMCOREINFO_BYTES \
+ +VMCOREINFO_NOTE_NAME_BYTES, \
+ PAGE_SIZE)

/* Location of a reserved region to hold the crash kernel.
*/
diff --git a/kernel/kexec.c b/kernel/kexec.c
index d1f365e..195de6d 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -43,7 +43,7 @@ note_buf_t __percpu *crash_notes;

/* vmcoreinfo stuff */
static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES];
-u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
+u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4] __aligned(PAGE_SIZE);
size_t vmcoreinfo_size;
size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data);