[dpdk-stable] patch 'mem: fix undefined behavior in NUMA-aware mapping' has been queued to LTS release 17.11.5

[Yongseok Koh]

Hi,

FYI, your patch has been queued to LTS release 17.11.5

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 12/01/18. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the patch applied
to the branch. If the code is different (ie: not only metadata diffs), due for example to
a change in context or macro names, please double check it.

Thanks.

Yongseok

---
>From df37e777d07eff975fbf500dc5f3313ddc756ae5 Mon Sep 17 00:00:00 2001
From: Anatoly Burakov <anatoly.burakov at intel.com>
Date: Fri, 21 Sep 2018 10:27:22 +0100
Subject: [PATCH] mem: fix undefined behavior in NUMA-aware mapping

[ upstream commit b1621823eacbe4669a4b581d6c420db08f9e6505 ]

When NUMA-aware hugepages config option is set, we rely on
libnuma to tell the kernel to allocate hugepages on a specific
NUMA node. However, we allocate node mask before we check if
NUMA is available in the first place, which, according to
the manpage [1], causes undefined behaviour.

Fix by only using nodemask when we have NUMA available.

[1] https://linux.die.net/man/3/numa_alloc_onnode

Bugzilla ID: 20
Fixes: 1b72605d2416 ("mem: balanced allocation of hugepages")

Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
Acked-by: Ilya Maximets <i.maximets at samsung.com>
---
 lib/librte_eal/linuxapp/eal/eal_memory.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c b/lib/librte_eal/linuxapp/eal/eal_memory.c
index 0675809b7..8d0456b56 100644
--- a/lib/librte_eal/linuxapp/eal/eal_memory.c
+++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
@@ -396,7 +396,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi,
 	int node_id = -1;
 	int essential_prev = 0;
 	int oldpolicy;
-	struct bitmask *oldmask = numa_allocate_nodemask();
+	struct bitmask *oldmask = NULL;
 	bool have_numa = true;
 	unsigned long maxnode = 0;
 
@@ -408,6 +408,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi,
 
 	if (orig && have_numa) {
 		RTE_LOG(DEBUG, EAL, "Trying to obtain current memory policy.\n");
+		oldmask = numa_allocate_nodemask();
 		if (get_mempolicy(&oldpolicy, oldmask->maskp,
 				  oldmask->size + 1, 0, 0) < 0) {
 			RTE_LOG(ERR, EAL,
@@ -603,7 +604,8 @@ out:
 			numa_set_localalloc();
 		}
 	}
-	numa_free_cpumask(oldmask);
+	if (oldmask != NULL)
+		numa_free_cpumask(oldmask);
 #endif
 	return i;
 }
-- 
2.11.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2018-11-29 15:01:46.882720528 -0800
+++ 0037-mem-fix-undefined-behavior-in-NUMA-aware-mapping.patch	2018-11-29 15:01:45.055965000 -0800
@@ -1,8 +1,10 @@
-From b1621823eacbe4669a4b581d6c420db08f9e6505 Mon Sep 17 00:00:00 2001
+From df37e777d07eff975fbf500dc5f3313ddc756ae5 Mon Sep 17 00:00:00 2001
 From: Anatoly Burakov <anatoly.burakov at intel.com>
 Date: Fri, 21 Sep 2018 10:27:22 +0100
 Subject: [PATCH] mem: fix undefined behavior in NUMA-aware mapping
 
+[ upstream commit b1621823eacbe4669a4b581d6c420db08f9e6505 ]
+
 When NUMA-aware hugepages config option is set, we rely on
 libnuma to tell the kernel to allocate hugepages on a specific
 NUMA node. However, we allocate node mask before we check if
@@ -15,7 +17,6 @@
 
 Bugzilla ID: 20
 Fixes: 1b72605d2416 ("mem: balanced allocation of hugepages")
-Cc: stable at dpdk.org
 
 Signed-off-by: Anatoly Burakov <anatoly.burakov at intel.com>
 Acked-by: Ilya Maximets <i.maximets at samsung.com>
@@ -24,10 +25,10 @@
  1 file changed, 4 insertions(+), 2 deletions(-)
 
 diff --git a/lib/librte_eal/linuxapp/eal/eal_memory.c b/lib/librte_eal/linuxapp/eal/eal_memory.c
-index e3ac24815..78bfa2241 100644
+index 0675809b7..8d0456b56 100644
 --- a/lib/librte_eal/linuxapp/eal/eal_memory.c
 +++ b/lib/librte_eal/linuxapp/eal/eal_memory.c
-@@ -264,7 +264,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi,
+@@ -396,7 +396,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi,
  	int node_id = -1;
  	int essential_prev = 0;
  	int oldpolicy;
@@ -36,15 +37,15 @@
  	bool have_numa = true;
  	unsigned long maxnode = 0;
  
-@@ -276,6 +276,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi,
+@@ -408,6 +408,7 @@ map_all_hugepages(struct hugepage_file *hugepg_tbl, struct hugepage_info *hpi,
  
- 	if (have_numa) {
+ 	if (orig && have_numa) {
  		RTE_LOG(DEBUG, EAL, "Trying to obtain current memory policy.\n");
 +		oldmask = numa_allocate_nodemask();
  		if (get_mempolicy(&oldpolicy, oldmask->maskp,
  				  oldmask->size + 1, 0, 0) < 0) {
  			RTE_LOG(ERR, EAL,
-@@ -403,7 +404,8 @@ out:
+@@ -603,7 +604,8 @@ out:
  			numa_set_localalloc();
  		}
  	}