On Sun, Jul 4, 2010 at 6:16 PM, Johannes Weiner <hannes@xxxxxxxxxxx> wrote:
> On Sun, Jul 04, 2010 at 05:22:33PM +0800, Bob Liu wrote:
>> Since a list entry may be removed, so use list_for_each_entry_safe
>> instead of list_for_each_entry.
>>
>> Signed-off-by: Bob Liu <lliubbo@xxxxxxxxx>
>> ---
>> mm/slob.c | 4 ++--
>> 1 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/mm/slob.c b/mm/slob.c
>> index 3f19a34..e2af18b 100644
>> --- a/mm/slob.c
>> +++ b/mm/slob.c
>> @@ -320,7 +320,7 @@ static void *slob_page_alloc(struct slob_page *sp, size_t size, int align)
>> */
>> static void *slob_alloc(size_t size, gfp_t gfp, int align, int node)
>> {
>> - struct slob_page *sp;
>> + struct slob_page *sp, *tmp;
>> struct list_head *prev;
>> struct list_head *slob_list;
>> slob_t *b = NULL;
>> @@ -335,7 +335,7 @@ static void *slob_alloc(size_t size, gfp_t gfp, int align, int node)
>>
>> spin_lock_irqsave(&slob_lock, flags);
>> /* Iterate through each partially free page, try to find room */
>> - list_for_each_entry(sp, slob_list, list) {
>> + list_for_each_entry_safe(sp, tmp, slob_list, list) {
>> #ifdef CONFIG_NUMA
>
> sp's list head is only modified if an allocation was successful, but
> then the iteration stops as well. So I see no reason for your patch.
> Did I overlook something?
>
Sorry, I am wrong. Please ignore this patch.
Thanks for your comment.
But It seems that the slob_list maybe have some member's next pointer NULL.
Because I triggered a NULL pointer access error.
And after I changed spin_lock_irqsave(&slob_lock, flags) before set slob_list.
This bug seems disappeared.
I will resend a patch, Please review.
Thanks!
--
Regards,
--Bob
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxxx For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href