Re: [PATCH v4 1/2] RDS: memory allocated must be align to 8

[santosh shilimkar <santosh.shilimkar@oracle.com>]

On 4/7/2016 4:57 AM, Shamir Rabinovitch wrote:
> Fix issue in 'rds_ib_cong_recv' when accessing unaligned memory
> allocated by 'rds_page_remainder_alloc' using uint64_t pointer.
>
Sorry I still didn't follow this change still. What exactly is the
problem.

> Signed-off-by: Shamir Rabinovitch <shamir.rabinovitch@oracle.com>
> ---
>   net/rds/page.c |    4 ++--
>   1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/net/rds/page.c b/net/rds/page.c
> index 616f21f..e2b5a58 100644
> --- a/net/rds/page.c
> +++ b/net/rds/page.c
> @@ -135,8 +135,8 @@ int rds_page_remainder_alloc(struct scatterlist *scat, unsigned long bytes,
>   			if (rem->r_offset != 0)
>   				rds_stats_inc(s_page_remainder_hit);
>
> -			rem->r_offset += bytes;
> -			if (rem->r_offset == PAGE_SIZE) {
> +			rem->r_offset += ALIGN(bytes, 8);
> +			if (rem->r_offset >= PAGE_SIZE) {
>   				__free_page(rem->r_page);
>   				rem->r_page = NULL;
>   			}
>