linux/net/tipc/net.c
Jon Maloy adba75be0d tipc: fix lockdep warning when reinitilaizing sockets
We get the following warning:

[   47.926140] 32-bit node address hash set to 2010a0a
[   47.927202]
[   47.927433] ================================
[   47.928050] WARNING: inconsistent lock state
[   47.928661] 4.19.0+ #37 Tainted: G            E
[   47.929346] --------------------------------
[   47.929954] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[   47.930116] swapper/3/0 [HC0[0]:SC1[3]:HE1:SE0] takes:
[   47.930116] 00000000af8bc31e (&(&ht->lock)->rlock){+.?.}, at: rhashtable_walk_enter+0x36/0xb0
[   47.930116] {SOFTIRQ-ON-W} state was registered at:
[   47.930116]   _raw_spin_lock+0x29/0x60
[   47.930116]   rht_deferred_worker+0x556/0x810
[   47.930116]   process_one_work+0x1f5/0x540
[   47.930116]   worker_thread+0x64/0x3e0
[   47.930116]   kthread+0x112/0x150
[   47.930116]   ret_from_fork+0x3a/0x50
[   47.930116] irq event stamp: 14044
[   47.930116] hardirqs last  enabled at (14044): [<ffffffff9a07fbba>] __local_bh_enable_ip+0x7a/0xf0
[   47.938117] hardirqs last disabled at (14043): [<ffffffff9a07fb81>] __local_bh_enable_ip+0x41/0xf0
[   47.938117] softirqs last  enabled at (14028): [<ffffffff9a0803ee>] irq_enter+0x5e/0x60
[   47.938117] softirqs last disabled at (14029): [<ffffffff9a0804a5>] irq_exit+0xb5/0xc0
[   47.938117]
[   47.938117] other info that might help us debug this:
[   47.938117]  Possible unsafe locking scenario:
[   47.938117]
[   47.938117]        CPU0
[   47.938117]        ----
[   47.938117]   lock(&(&ht->lock)->rlock);
[   47.938117]   <Interrupt>
[   47.938117]     lock(&(&ht->lock)->rlock);
[   47.938117]
[   47.938117]  *** DEADLOCK ***
[   47.938117]
[   47.938117] 2 locks held by swapper/3/0:
[   47.938117]  #0: 0000000062c64f90 ((&d->timer)){+.-.}, at: call_timer_fn+0x5/0x280
[   47.938117]  #1: 00000000ee39619c (&(&d->lock)->rlock){+.-.}, at: tipc_disc_timeout+0xc8/0x540 [tipc]
[   47.938117]
[   47.938117] stack backtrace:
[   47.938117] CPU: 3 PID: 0 Comm: swapper/3 Tainted: G            E     4.19.0+ #37
[   47.938117] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   47.938117] Call Trace:
[   47.938117]  <IRQ>
[   47.938117]  dump_stack+0x5e/0x8b
[   47.938117]  print_usage_bug+0x1ed/0x1ff
[   47.938117]  mark_lock+0x5b5/0x630
[   47.938117]  __lock_acquire+0x4c0/0x18f0
[   47.938117]  ? lock_acquire+0xa6/0x180
[   47.938117]  lock_acquire+0xa6/0x180
[   47.938117]  ? rhashtable_walk_enter+0x36/0xb0
[   47.938117]  _raw_spin_lock+0x29/0x60
[   47.938117]  ? rhashtable_walk_enter+0x36/0xb0
[   47.938117]  rhashtable_walk_enter+0x36/0xb0
[   47.938117]  tipc_sk_reinit+0xb0/0x410 [tipc]
[   47.938117]  ? mark_held_locks+0x6f/0x90
[   47.938117]  ? __local_bh_enable_ip+0x7a/0xf0
[   47.938117]  ? lockdep_hardirqs_on+0x20/0x1a0
[   47.938117]  tipc_net_finalize+0xbf/0x180 [tipc]
[   47.938117]  tipc_disc_timeout+0x509/0x540 [tipc]
[   47.938117]  ? call_timer_fn+0x5/0x280
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  call_timer_fn+0xa1/0x280
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  run_timer_softirq+0x1f2/0x4d0
[   47.938117]  __do_softirq+0xfc/0x413
[   47.938117]  irq_exit+0xb5/0xc0
[   47.938117]  smp_apic_timer_interrupt+0xac/0x210
[   47.938117]  apic_timer_interrupt+0xf/0x20
[   47.938117]  </IRQ>
[   47.938117] RIP: 0010:default_idle+0x1c/0x140
[   47.938117] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 41 54 55 53 65 8b 2d d8 2b 74 65 0f 1f 44 00 00 e8 c6 2c 8b ff fb f4 <65> 8b 2d c5 2b 74 65 0f 1f 44 00 00 5b 5d 41 5c c3 65 8b 05 b4 2b
[   47.938117] RSP: 0018:ffffaf6ac0207ec8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
[   47.938117] RAX: ffff8f5b3735e200 RBX: 0000000000000003 RCX: 0000000000000001
[   47.938117] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8f5b3735e200
[   47.938117] RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000000
[   47.938117] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[   47.938117] R13: 0000000000000000 R14: ffff8f5b3735e200 R15: ffff8f5b3735e200
[   47.938117]  ? default_idle+0x1a/0x140
[   47.938117]  do_idle+0x1bc/0x280
[   47.938117]  cpu_startup_entry+0x19/0x20
[   47.938117]  start_secondary+0x187/0x1c0
[   47.938117]  secondary_startup_64+0xa4/0xb0

The reason seems to be that tipc_net_finalize()->tipc_sk_reinit() is
calling the function rhashtable_walk_enter() within a timer interrupt.
We fix this by executing tipc_net_finalize() in work queue context.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-17 22:01:31 -08:00

306 lines
9.3 KiB
C

/*
* net/tipc/net.c: TIPC network routing code
*
* Copyright (c) 1995-2006, 2014, Ericsson AB
* Copyright (c) 2005, 2010-2011, Wind River Systems
* All rights reserved.
*
* 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.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "core.h"
#include "net.h"
#include "name_distr.h"
#include "subscr.h"
#include "socket.h"
#include "node.h"
#include "bcast.h"
#include "netlink.h"
/*
* The TIPC locking policy is designed to ensure a very fine locking
* granularity, permitting complete parallel access to individual
* port and node/link instances. The code consists of four major
* locking domains, each protected with their own disjunct set of locks.
*
* 1: The bearer level.
* RTNL lock is used to serialize the process of configuring bearer
* on update side, and RCU lock is applied on read side to make
* bearer instance valid on both paths of message transmission and
* reception.
*
* 2: The node and link level.
* All node instances are saved into two tipc_node_list and node_htable
* lists. The two lists are protected by node_list_lock on write side,
* and they are guarded with RCU lock on read side. Especially node
* instance is destroyed only when TIPC module is removed, and we can
* confirm that there has no any user who is accessing the node at the
* moment. Therefore, Except for iterating the two lists within RCU
* protection, it's no needed to hold RCU that we access node instance
* in other places.
*
* In addition, all members in node structure including link instances
* are protected by node spin lock.
*
* 3: The transport level of the protocol.
* This consists of the structures port, (and its user level
* representations, such as user_port and tipc_sock), reference and
* tipc_user (port.c, reg.c, socket.c).
*
* This layer has four different locks:
* - The tipc_port spin_lock. This is protecting each port instance
* from parallel data access and removal. Since we can not place
* this lock in the port itself, it has been placed in the
* corresponding reference table entry, which has the same life
* cycle as the module. This entry is difficult to access from
* outside the TIPC core, however, so a pointer to the lock has
* been added in the port instance, -to be used for unlocking
* only.
* - A read/write lock to protect the reference table itself (teg.c).
* (Nobody is using read-only access to this, so it can just as
* well be changed to a spin_lock)
* - A spin lock to protect the registry of kernel/driver users (reg.c)
* - A global spin_lock (tipc_port_lock), which only task is to ensure
* consistency where more than one port is involved in an operation,
* i.e., whe a port is part of a linked list of ports.
* There are two such lists; 'port_list', which is used for management,
* and 'wait_list', which is used to queue ports during congestion.
*
* 4: The name table (name_table.c, name_distr.c, subscription.c)
* - There is one big read/write-lock (tipc_nametbl_lock) protecting the
* overall name table structure. Nothing must be added/removed to
* this structure without holding write access to it.
* - There is one local spin_lock per sub_sequence, which can be seen
* as a sub-domain to the tipc_nametbl_lock domain. It is used only
* for translation operations, and is needed because a translation
* steps the root of the 'publication' linked list between each lookup.
* This is always used within the scope of a tipc_nametbl_lock(read).
* - A local spin_lock protecting the queue of subscriber events.
*/
struct tipc_net_work {
struct work_struct work;
struct net *net;
u32 addr;
};
static void tipc_net_finalize(struct net *net, u32 addr);
int tipc_net_init(struct net *net, u8 *node_id, u32 addr)
{
if (tipc_own_id(net)) {
pr_info("Cannot configure node identity twice\n");
return -1;
}
pr_info("Started in network mode\n");
if (node_id)
tipc_set_node_id(net, node_id);
if (addr)
tipc_net_finalize(net, addr);
return 0;
}
static void tipc_net_finalize(struct net *net, u32 addr)
{
struct tipc_net *tn = tipc_net(net);
if (cmpxchg(&tn->node_addr, 0, addr))
return;
tipc_set_node_addr(net, addr);
tipc_named_reinit(net);
tipc_sk_reinit(net);
tipc_nametbl_publish(net, TIPC_CFG_SRV, addr, addr,
TIPC_CLUSTER_SCOPE, 0, addr);
}
static void tipc_net_finalize_work(struct work_struct *work)
{
struct tipc_net_work *fwork;
fwork = container_of(work, struct tipc_net_work, work);
tipc_net_finalize(fwork->net, fwork->addr);
kfree(fwork);
}
void tipc_sched_net_finalize(struct net *net, u32 addr)
{
struct tipc_net_work *fwork = kzalloc(sizeof(*fwork), GFP_ATOMIC);
if (!fwork)
return;
INIT_WORK(&fwork->work, tipc_net_finalize_work);
fwork->net = net;
fwork->addr = addr;
schedule_work(&fwork->work);
}
void tipc_net_stop(struct net *net)
{
u32 self = tipc_own_addr(net);
if (!self)
return;
tipc_nametbl_withdraw(net, TIPC_CFG_SRV, self, self, self);
rtnl_lock();
tipc_bearer_stop(net);
tipc_node_stop(net);
rtnl_unlock();
pr_info("Left network mode\n");
}
static int __tipc_nl_add_net(struct net *net, struct tipc_nl_msg *msg)
{
struct tipc_net *tn = net_generic(net, tipc_net_id);
u64 *w0 = (u64 *)&tn->node_id[0];
u64 *w1 = (u64 *)&tn->node_id[8];
struct nlattr *attrs;
void *hdr;
hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
NLM_F_MULTI, TIPC_NL_NET_GET);
if (!hdr)
return -EMSGSIZE;
attrs = nla_nest_start(msg->skb, TIPC_NLA_NET);
if (!attrs)
goto msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_NET_ID, tn->net_id))
goto attr_msg_full;
if (nla_put_u64_64bit(msg->skb, TIPC_NLA_NET_NODEID, *w0, 0))
goto attr_msg_full;
if (nla_put_u64_64bit(msg->skb, TIPC_NLA_NET_NODEID_W1, *w1, 0))
goto attr_msg_full;
nla_nest_end(msg->skb, attrs);
genlmsg_end(msg->skb, hdr);
return 0;
attr_msg_full:
nla_nest_cancel(msg->skb, attrs);
msg_full:
genlmsg_cancel(msg->skb, hdr);
return -EMSGSIZE;
}
int tipc_nl_net_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
int err;
int done = cb->args[0];
struct tipc_nl_msg msg;
if (done)
return 0;
msg.skb = skb;
msg.portid = NETLINK_CB(cb->skb).portid;
msg.seq = cb->nlh->nlmsg_seq;
err = __tipc_nl_add_net(net, &msg);
if (err)
goto out;
done = 1;
out:
cb->args[0] = done;
return skb->len;
}
int __tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info)
{
struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
struct net *net = sock_net(skb->sk);
struct tipc_net *tn = tipc_net(net);
int err;
if (!info->attrs[TIPC_NLA_NET])
return -EINVAL;
err = nla_parse_nested(attrs, TIPC_NLA_NET_MAX,
info->attrs[TIPC_NLA_NET], tipc_nl_net_policy,
info->extack);
if (err)
return err;
/* Can't change net id once TIPC has joined a network */
if (tipc_own_addr(net))
return -EPERM;
if (attrs[TIPC_NLA_NET_ID]) {
u32 val;
val = nla_get_u32(attrs[TIPC_NLA_NET_ID]);
if (val < 1 || val > 9999)
return -EINVAL;
tn->net_id = val;
}
if (attrs[TIPC_NLA_NET_ADDR]) {
u32 addr;
addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
if (!addr)
return -EINVAL;
tn->legacy_addr_format = true;
tipc_net_init(net, NULL, addr);
}
if (attrs[TIPC_NLA_NET_NODEID]) {
u8 node_id[NODE_ID_LEN];
u64 *w0 = (u64 *)&node_id[0];
u64 *w1 = (u64 *)&node_id[8];
if (!attrs[TIPC_NLA_NET_NODEID_W1])
return -EINVAL;
*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
tipc_net_init(net, node_id, 0);
}
return 0;
}
int tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info)
{
int err;
rtnl_lock();
err = __tipc_nl_net_set(skb, info);
rtnl_unlock();
return err;
}