Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933148AbbGUPcv (ORCPT ); Tue, 21 Jul 2015 11:32:51 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:38520 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754360AbbGUPct (ORCPT ); Tue, 21 Jul 2015 11:32:49 -0400 From: Chris J Arges To: pshelar@nicira.com Cc: linuxppc-dev@lists.ozlabs.org, nacc@linux.vnet.ibm.com, benh@kernel.crashing.org, linux-numa@vger.kernel.org, Chris J Arges , "David S. Miller" , netdev@vger.kernel.org, dev@openvswitch.org, linux-kernel@vger.kernel.org Subject: [PATCH] openvswitch: make for_each_node loops work with sparse numa systems Date: Tue, 21 Jul 2015 10:32:34 -0500 Message-Id: <1437492756-22777-1-git-send-email-chris.j.arges@canonical.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3724 Lines: 126 Some architectures like POWER can have a NUMA node_possible_map that contains sparse entries. This causes memory corruption with openvswitch since it allocates flow_cache with a multiple of num_possible_nodes() and assumes the node variable returned by for_each_node will index into flow->stats[node]. For example, if node_possible_map is 0x30003, this patch will map node to node_cnt as follows: 0,1,16,17 => 0,1,2,3 The crash was noticed after 3af229f2 was applied as it changed the node_possible_map to match node_online_map on boot. Fixes: 3af229f2071f5b5cb31664be6109561fbe19c861 Signed-off-by: Chris J Arges --- net/openvswitch/flow.c | 10 ++++++---- net/openvswitch/flow_table.c | 18 +++++++++++------- 2 files changed, 17 insertions(+), 11 deletions(-) diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c index bc7b0ab..425d45d 100644 --- a/net/openvswitch/flow.c +++ b/net/openvswitch/flow.c @@ -134,14 +134,14 @@ void ovs_flow_stats_get(const struct sw_flow *flow, struct ovs_flow_stats *ovs_stats, unsigned long *used, __be16 *tcp_flags) { - int node; + int node, node_cnt = 0; *used = 0; *tcp_flags = 0; memset(ovs_stats, 0, sizeof(*ovs_stats)); for_each_node(node) { - struct flow_stats *stats = rcu_dereference_ovsl(flow->stats[node]); + struct flow_stats *stats = rcu_dereference_ovsl(flow->stats[node_cnt]); if (stats) { /* Local CPU may write on non-local stats, so we must @@ -155,16 +155,17 @@ void ovs_flow_stats_get(const struct sw_flow *flow, ovs_stats->n_bytes += stats->byte_count; spin_unlock_bh(&stats->lock); } + node_cnt++; } } /* Called with ovs_mutex. */ void ovs_flow_stats_clear(struct sw_flow *flow) { - int node; + int node, node_cnt = 0; for_each_node(node) { - struct flow_stats *stats = ovsl_dereference(flow->stats[node]); + struct flow_stats *stats = ovsl_dereference(flow->stats[node_cnt]); if (stats) { spin_lock_bh(&stats->lock); @@ -174,6 +175,7 @@ void ovs_flow_stats_clear(struct sw_flow *flow) stats->tcp_flags = 0; spin_unlock_bh(&stats->lock); } + node_cnt++; } } diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c index 4613df8..5d10c54 100644 --- a/net/openvswitch/flow_table.c +++ b/net/openvswitch/flow_table.c @@ -77,7 +77,7 @@ struct sw_flow *ovs_flow_alloc(void) { struct sw_flow *flow; struct flow_stats *stats; - int node; + int node, node_cnt = 0; flow = kmem_cache_alloc(flow_cache, GFP_KERNEL); if (!flow) @@ -99,9 +99,11 @@ struct sw_flow *ovs_flow_alloc(void) RCU_INIT_POINTER(flow->stats[0], stats); - for_each_node(node) + for_each_node(node) { if (node != 0) - RCU_INIT_POINTER(flow->stats[node], NULL); + RCU_INIT_POINTER(flow->stats[node_cnt], NULL); + node_cnt++; + } return flow; err: @@ -139,15 +141,17 @@ static struct flex_array *alloc_buckets(unsigned int n_buckets) static void flow_free(struct sw_flow *flow) { - int node; + int node, node_cnt = 0; if (ovs_identifier_is_key(&flow->id)) kfree(flow->id.unmasked_key); kfree((struct sw_flow_actions __force *)flow->sf_acts); - for_each_node(node) - if (flow->stats[node]) + for_each_node(node) { + if (flow->stats[node_cnt]) kmem_cache_free(flow_stats_cache, - (struct flow_stats __force *)flow->stats[node]); + (struct flow_stats __force *)flow->stats[node_cnt]); + node_cnt++; + } kmem_cache_free(flow_cache, flow); } -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/