2011-02-06 13:31:38

by Namhyung Kim

Subject: [PATCH] memblock: Fix error path in memblock_add_region()

@type->regions should be restored if memblock_double_array() fails.

Signed-off-by: Namhyung Kim <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Yinghai Lu <[email protected]>
---
mm/memblock.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/mm/memblock.c b/mm/memblock.c
index bdba245d8afd..49284f9f99a6 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -379,6 +379,10 @@ static long __init_memblock memblock_add_region(struct memblock_type *type, phys
*/
if (type->cnt == type->max && memblock_double_array(type)) {
type->cnt--;
+ for (++i; i < type->cnt; i++) {
+ type->regions[i].base = type->regions[i+1].base;
+ type->regions[i].size = type->regions[i+1].size;
+ }
return -1;
}

--
1.7.3.4.600.g982838b0

2011-02-06 17:47:12

by Yinghai Lu

Subject: Re: [PATCH] memblock: Fix error path in memblock_add_region()

On 02/06/2011 05:31 AM, Namhyung Kim wrote:
> @type->regions should be restored if memblock_double_array() fails.
>
> Signed-off-by: Namhyung Kim <[email protected]>
> Cc: Benjamin Herrenschmidt <[email protected]>
> Cc: Yinghai Lu <[email protected]>
> ---
> mm/memblock.c | 4 ++++
> 1 files changed, 4 insertions(+), 0 deletions(-)
>
> diff --git a/mm/memblock.c b/mm/memblock.c
> index bdba245d8afd..49284f9f99a6 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -379,6 +379,10 @@ static long __init_memblock memblock_add_region(struct memblock_type *type, phys
> */
> if (type->cnt == type->max && memblock_double_array(type)) {
> type->cnt--;
> + for (++i; i < type->cnt; i++) {
> + type->regions[i].base = type->regions[i+1].base;
> + type->regions[i].size = type->regions[i+1].size;
> + }
> return -1;
> }
>

we can skip the restoring.

Thanks

Yinghai

diff --git a/mm/memblock.c b/mm/memblock.c
index bdba245..3231657 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -374,13 +374,9 @@ static long __init_memblock memblock_add_region(struct memblock_type *type, phys
}
type->cnt++;

- /* The array is full ? Try to resize it. If that fails, we undo
- * our allocation and return an error
- */
- if (type->cnt == type->max && memblock_double_array(type)) {
- type->cnt--;
+ /* The array is full ? Try to resize it */
+ if (type->cnt == type->max && memblock_double_array(type))
return -1;
- }

return 0;
}

2011-02-07 05:00:36

by Namhyung Kim

Subject: Re: [PATCH] memblock: Fix error path in memblock_add_region()

2011-02-06 (일), 09:46 -0800, Yinghai Lu:
> we can skip the restoring.
>
> Thanks
>
> Yinghai
>
> diff --git a/mm/memblock.c b/mm/memblock.c
> index bdba245..3231657 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -374,13 +374,9 @@ static long __init_memblock memblock_add_region(struct memblock_type *type, phys
> }
> type->cnt++;
>
> - /* The array is full ? Try to resize it. If that fails, we undo
> - * our allocation and return an error
> - */
> - if (type->cnt == type->max && memblock_double_array(type)) {
> - type->cnt--;
> + /* The array is full ? Try to resize it */
> + if (type->cnt == type->max && memblock_double_array(type))
> return -1;
> - }
>
> return 0;
> }

Looks OK to me, too.
Thanks.


--
Regards,
Namhyung Kim