4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jon Maloy donmalo99@gmail.com
[ Upstream commit adba75be0d23cca92a028749d92c60c8909bbdb3 ]
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/tipc/discover.c | 19 ++++++++++--------- net/tipc/net.c | 45 +++++++++++++++++++++++++++++++++++++-------- net/tipc/net.h | 2 +- 3 files changed, 48 insertions(+), 18 deletions(-)
--- a/net/tipc/discover.c +++ b/net/tipc/discover.c @@ -166,7 +166,8 @@ static bool tipc_disc_addr_trial_msg(str
/* Apply trial address if we just left trial period */ if (!trial && !self) { - tipc_net_finalize(net, tn->trial_addr); + tipc_sched_net_finalize(net, tn->trial_addr); + msg_set_prevnode(buf_msg(d->skb), tn->trial_addr); msg_set_type(buf_msg(d->skb), DSC_REQ_MSG); }
@@ -300,14 +301,12 @@ static void tipc_disc_timeout(struct tim goto exit; }
- /* Trial period over ? */ - if (!time_before(jiffies, tn->addr_trial_end)) { - /* Did we just leave it ? */ - if (!tipc_own_addr(net)) - tipc_net_finalize(net, tn->trial_addr); - - msg_set_type(buf_msg(d->skb), DSC_REQ_MSG); - msg_set_prevnode(buf_msg(d->skb), tipc_own_addr(net)); + /* Did we just leave trial period ? */ + if (!time_before(jiffies, tn->addr_trial_end) && !tipc_own_addr(net)) { + mod_timer(&d->timer, jiffies + TIPC_DISC_INIT); + spin_unlock_bh(&d->lock); + tipc_sched_net_finalize(net, tn->trial_addr); + return; }
/* Adjust timeout interval according to discovery phase */ @@ -319,6 +318,8 @@ static void tipc_disc_timeout(struct tim d->timer_intv = TIPC_DISC_SLOW; else if (!d->num_nodes && d->timer_intv > TIPC_DISC_FAST) d->timer_intv = TIPC_DISC_FAST; + msg_set_type(buf_msg(d->skb), DSC_REQ_MSG); + msg_set_prevnode(buf_msg(d->skb), tn->trial_addr); }
mod_timer(&d->timer, jiffies + d->timer_intv); --- a/net/tipc/net.c +++ b/net/tipc/net.c @@ -104,6 +104,14 @@ * - 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)) { @@ -119,17 +127,38 @@ int tipc_net_init(struct net *net, u8 *n return 0; }
-void tipc_net_finalize(struct net *net, u32 addr) +static void tipc_net_finalize(struct net *net, u32 addr) { struct tipc_net *tn = tipc_net(net);
- if (!cmpxchg(&tn->node_addr, 0, addr)) { - 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); - } + 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) --- a/net/tipc/net.h +++ b/net/tipc/net.h @@ -42,7 +42,7 @@ extern const struct nla_policy tipc_nl_net_policy[];
int tipc_net_init(struct net *net, u8 *node_id, u32 addr); -void tipc_net_finalize(struct net *net, u32 addr); +void tipc_sched_net_finalize(struct net *net, u32 addr); void tipc_net_stop(struct net *net); int tipc_nl_net_dump(struct sk_buff *skb, struct netlink_callback *cb); int tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info);