| From 58995ce91b62da5633298620a5cf5862f381223c Mon Sep 17 00:00:00 2001 |
| From: Luis Claudio R. Goncalves <lclaudio@uudg.org> |
| Date: Sat, 27 Nov 2010 13:04:05 -0200 |
| Subject: [PATCH] net: ebtables: Work around per cpu assumptions |
| |
| commit a1026af461530b4f0a875c4bdffac4137b2db549 in tip. |
| |
| I have been seeing several variations of this BUG message: |
| |
| BUG: using smp_processor_id() in preemptible [00000000] code: ... |
| caller is ebt_do_table+0x94/0x60c [ebtables] |
| |
| Disable preemption while fetching and using the ID of the current CPU. |
| |
| Signed-off-by: "Luis Claudio R. Goncalves" <lclaudio@uudg.org> |
| Signed-off-by: Thomas Gleixner <tglx@linutronix.de> |
| |
| diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c |
| index dfb5805..1946471 100644 |
| --- a/net/bridge/netfilter/ebtables.c |
| +++ b/net/bridge/netfilter/ebtables.c |
| @@ -176,7 +176,7 @@ unsigned int ebt_do_table (unsigned int hook, struct sk_buff *skb, |
| const struct net_device *in, const struct net_device *out, |
| struct ebt_table *table) |
| { |
| - int i, nentries; |
| + int i, nentries, cpu; |
| struct ebt_entry *point; |
| struct ebt_counter *counter_base, *cb_base; |
| const struct ebt_entry_target *t; |
| @@ -197,12 +197,14 @@ unsigned int ebt_do_table (unsigned int hook, struct sk_buff *skb, |
| |
| read_lock_bh(&table->lock); |
| private = table->private; |
| - cb_base = COUNTER_BASE(private->counters, private->nentries, |
| - smp_processor_id()); |
| + preempt_disable_rt(); |
| + cpu = smp_processor_id(); |
| + cb_base = COUNTER_BASE(private->counters, private->nentries, cpu); |
| if (private->chainstack) |
| - cs = private->chainstack[smp_processor_id()]; |
| + cs = private->chainstack[cpu]; |
| else |
| cs = NULL; |
| + preempt_enable_rt(); |
| chaininfo = private->hook_entry[hook]; |
| nentries = private->hook_entry[hook]->nentries; |
| point = (struct ebt_entry *)(private->hook_entry[hook]->data); |
| -- |
| 1.7.1.1 |
| |