Re: [PATCH net-next RFC v2 1/3] lwt: infrastructure to support light weight tunnels

[roopa <roopa@cumulusnetworks.com>]

On 6/20/15, 9:38 AM, Nikolay Aleksandrov wrote:
> <<<snip>>>
>> diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c
>> new file mode 100644
>> index 0000000..29c7802
>> --- /dev/null
>> +++ b/net/core/lwtunnel.c
>> @@ -0,0 +1,162 @@
>> +/*
>> + * lwtunnel	Infrastructure for light weight tunnels like mpls
>> + *
>> + *
>> + *		This program is free software; you can redistribute it and/or
>> + *		modify it under the terms of the GNU General Public License
>> + *		as published by the Free Software Foundation; either version
>> + *		2 of the License, or (at your option) any later version.
>> + *
>> + */
>> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>> +
>> +#include <linux/capability.h>
>> +#include <linux/module.h>
>> +#include <linux/types.h>
>> +#include <linux/kernel.h>
>> +#include <linux/slab.h>
>> +#include <linux/uaccess.h>
>> +#include <linux/skbuff.h>
>> +#include <linux/netdevice.h>
>> +#include <linux/in.h>
>> +#include <linux/init.h>
>> +#include <linux/err.h>
>> +
>> +#include <net/lwtunnel.h>
>> +#include <net/rtnetlink.h>
>> +
>> +struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len)
>> +{
>> +	struct lwtunnel_state *lws;
>> +
>> +	return kzalloc(sizeof(*lws) + hdr_len, GFP_KERNEL);
> This seems to be called with rcu_read_lock so GFP_ATOMIC  would have to
> be used. (Judging by patch 3/3’s mpls_build_state and lwtunnel_build_state)
>
yep, correct. thanks