Re: [PATCH] sunrpc: verbs: Avoid 1kb stack

From: J. Bruce Fields
Date: Tue Jan 08 2013 - 09:45:57 EST


On Mon, Jan 07, 2013 at 11:41:36AM -0800, Joe Perches wrote:
> 16 * 64 is a bit much.
> Use kmalloc_array instead.

I thought there was some reason we didn't do this.

Grepping up through the callers.... It looks like the result is
xprt_rdma_send_request returns -EIO, and as far as I can tell that gets
passed up to the application on the client. That doesn't sound right.

--b.

>
> Signed-off-by: Joe Perches <joe@xxxxxxxxxxx>
> ---
> net/sunrpc/xprtrdma/verbs.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c
> index 745973b..9cfebb4 100644
> --- a/net/sunrpc/xprtrdma/verbs.c
> +++ b/net/sunrpc/xprtrdma/verbs.c
> @@ -1736,8 +1736,13 @@ rpcrdma_register_default_external(struct rpcrdma_mr_seg *seg,
> int mem_priv = (writing ? IB_ACCESS_REMOTE_WRITE :
> IB_ACCESS_REMOTE_READ);
> struct rpcrdma_mr_seg *seg1 = seg;
> - struct ib_phys_buf ipb[RPCRDMA_MAX_DATA_SEGS];
> int len, i, rc = 0;
> + struct ib_phys_buf *ipb = kmalloc_array(RPCRDMA_MAX_DATA_SEGS,
> + sizeof(*ipb),
> + GFP_KERNEL);
> +
> + if (!ipb)
> + return -ENOMEM;
>
> if (*nsegs > RPCRDMA_MAX_DATA_SEGS)
> *nsegs = RPCRDMA_MAX_DATA_SEGS;
> @@ -1770,6 +1775,9 @@ rpcrdma_register_default_external(struct rpcrdma_mr_seg *seg,
> seg1->mr_len = len;
> }
> *nsegs = i;
> +
> + kfree(ipb);
> +
> return rc;
> }
>
>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/