linux/drivers/net/ethernet/netronome/nfp/flower/cmsg.c
Simon Horman bb3afda4fc nfp: do not update MTU from BH in flower app
The Flower app may receive a request to update the MTU of a representor
netdev upon receipt of a control message from the firmware. This requires
the RTNL lock which needs to be taken outside of the packet processing
path.

As a handling of this correctly seems a little to invasive for a fix simply
skip setting the MTU for now.

Relevant backtrace:
 [ 1496.288489] BUG: scheduling while atomic: kworker/0:3/373/0x00000100
 [ 1496.294911]  dca syscopyarea sysfillrect sysimgblt fb_sys_fops ptp drm mxm_wmi ahci pps_core libahci i2c_algo_bit wmi [last unloaded: nfp]
 [ 1496.294918] CPU: 0 PID: 373 Comm: kworker/0:3 Tainted: G           OE   4.13.0-rc3+ #3
 [ 1496.294919] Hardware name: Supermicro X10DRi/X10DRi, BIOS 2.0 12/28/2015
 [ 1496.294923] Workqueue: events work_for_cpu_fn
 [ 1496.294924] Call Trace:
 [ 1496.294927]  <IRQ>
 [ 1496.294931]  dump_stack+0x63/0x82
 [ 1496.294935]  __schedule_bug+0x54/0x70
 [ 1496.294937]  __schedule+0x62f/0x890
 [ 1496.294941]  ? intel_unmap_sg+0x90/0x90
 [ 1496.294942]  schedule+0x36/0x80
 [ 1496.294943]  schedule_preempt_disabled+0xe/0x10
 [ 1496.294945]  __mutex_lock.isra.2+0x445/0x4a0
 [ 1496.294947]  ? device_is_rmrr_locked+0x12/0x50
 [ 1496.294950]  ? kfree+0x162/0x170
 [ 1496.294952]  ? device_is_rmrr_locked+0x12/0x50
 [ 1496.294953]  ? iommu_should_identity_map+0x50/0xe0
 [ 1496.294954]  __mutex_lock_slowpath+0x13/0x20
 [ 1496.294955]  ? iommu_no_mapping+0x48/0xd0
 [ 1496.294956]  ? __mutex_lock_slowpath+0x13/0x20
 [ 1496.294957]  mutex_lock+0x2f/0x40
 [ 1496.294960]  rtnl_lock+0x15/0x20
 [ 1496.294979]  nfp_flower_cmsg_rx+0xc8/0x150 [nfp]
 [ 1496.294986]  nfp_ctrl_poll+0x286/0x350 [nfp]
 [ 1496.294989]  tasklet_action+0xf6/0x110
 [ 1496.294992]  __do_softirq+0xed/0x278
 [ 1496.294993]  irq_exit+0xb6/0xc0
 [ 1496.294994]  do_IRQ+0x4f/0xd0
 [ 1496.294996]  common_interrupt+0x89/0x89

Fixes: 948faa46c0 ("nfp: add support for control messages for flower app")
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 14:50:09 -07:00

154 lines
4.1 KiB
C

/*
* Copyright (C) 2015-2017 Netronome Systems, Inc.
*
* This software is dual licensed under the GNU General License Version 2,
* June 1991 as shown in the file COPYING in the top-level directory of this
* source tree or the BSD 2-Clause License provided below. You have the
* option to license this software under the complete terms of either license.
*
* The BSD 2-Clause License:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/bitfield.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <net/dst_metadata.h>
#include "main.h"
#include "../nfpcore/nfp_cpp.h"
#include "../nfp_net_repr.h"
#include "./cmsg.h"
#define nfp_flower_cmsg_warn(app, fmt, args...) \
do { \
if (net_ratelimit()) \
nfp_warn((app)->cpp, fmt, ## args); \
} while (0)
static struct nfp_flower_cmsg_hdr *
nfp_flower_cmsg_get_hdr(struct sk_buff *skb)
{
return (struct nfp_flower_cmsg_hdr *)skb->data;
}
struct sk_buff *
nfp_flower_cmsg_alloc(struct nfp_app *app, unsigned int size,
enum nfp_flower_cmsg_type_port type)
{
struct nfp_flower_cmsg_hdr *ch;
struct sk_buff *skb;
size += NFP_FLOWER_CMSG_HLEN;
skb = nfp_app_ctrl_msg_alloc(app, size, GFP_KERNEL);
if (!skb)
return NULL;
ch = nfp_flower_cmsg_get_hdr(skb);
ch->pad = 0;
ch->version = NFP_FLOWER_CMSG_VER1;
ch->type = type;
skb_put(skb, size);
return skb;
}
int nfp_flower_cmsg_portmod(struct nfp_repr *repr, bool carrier_ok)
{
struct nfp_flower_cmsg_portmod *msg;
struct sk_buff *skb;
skb = nfp_flower_cmsg_alloc(repr->app, sizeof(*msg),
NFP_FLOWER_CMSG_TYPE_PORT_MOD);
if (!skb)
return -ENOMEM;
msg = nfp_flower_cmsg_get_data(skb);
msg->portnum = cpu_to_be32(repr->dst->u.port_info.port_id);
msg->reserved = 0;
msg->info = carrier_ok;
msg->mtu = cpu_to_be16(repr->netdev->mtu);
nfp_ctrl_tx(repr->app->ctrl, skb);
return 0;
}
static void
nfp_flower_cmsg_portmod_rx(struct nfp_app *app, struct sk_buff *skb)
{
struct nfp_flower_cmsg_portmod *msg;
struct net_device *netdev;
bool link;
msg = nfp_flower_cmsg_get_data(skb);
link = msg->info & NFP_FLOWER_CMSG_PORTMOD_INFO_LINK;
rcu_read_lock();
netdev = nfp_app_repr_get(app, be32_to_cpu(msg->portnum));
if (!netdev) {
nfp_flower_cmsg_warn(app, "ctrl msg for unknown port 0x%08x\n",
be32_to_cpu(msg->portnum));
rcu_read_unlock();
return;
}
if (link)
netif_carrier_on(netdev);
else
netif_carrier_off(netdev);
rcu_read_unlock();
}
void nfp_flower_cmsg_rx(struct nfp_app *app, struct sk_buff *skb)
{
struct nfp_flower_cmsg_hdr *cmsg_hdr;
enum nfp_flower_cmsg_type_port type;
cmsg_hdr = nfp_flower_cmsg_get_hdr(skb);
if (unlikely(cmsg_hdr->version != NFP_FLOWER_CMSG_VER1)) {
nfp_flower_cmsg_warn(app, "Cannot handle repr control version %u\n",
cmsg_hdr->version);
goto out;
}
type = cmsg_hdr->type;
switch (type) {
case NFP_FLOWER_CMSG_TYPE_PORT_MOD:
nfp_flower_cmsg_portmod_rx(app, skb);
break;
case NFP_FLOWER_CMSG_TYPE_FLOW_STATS:
nfp_flower_rx_flow_stats(app, skb);
break;
default:
nfp_flower_cmsg_warn(app, "Cannot handle invalid repr control type %u\n",
type);
}
out:
dev_kfree_skb_any(skb);
}