[PATCH v3 12/21] vmcore: allocate per-cpu crash_notes objects on page-size boundary

HATAYAMA Daisuke
2013-03-19T02:31:11Z

To satisfy mmap()'s page-size boundary requirement, allocate per-cpu
crash_notes objects on page-size boundary.

/proc/vmcore on the 2nd kernel checks if each note objects is
allocated on page-size boundary. If there's some object not satisfying
the page-size boundary requirement, /proc/vmcore doesn't provide
mmap() interface.

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

kernel/kexec.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/kernel/kexec.c b/kernel/kexec.c
index bddd3d7..d1f365e 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -1234,7 +1234,8 @@ void crash_save_cpu(struct pt_regs *regs, int cpu)
static int __init crash_notes_memory_init(void)
{
/* Allocate memory for saving cpu registers. */
- crash_notes = alloc_percpu(note_buf_t);
+ crash_notes = __alloc_percpu(roundup(sizeof(note_buf_t), PAGE_SIZE),
+ PAGE_SIZE);
if (!crash_notes) {
printk("Kexec: Memory allocation for saving cpu register"
" states failed\n");