summaryrefslogtreecommitdiffstats
path: root/kernel
diff options
context:
space:
mode:
authorTang Chen <tangchen@cn.fujitsu.com>2012-09-25 21:12:30 +0800
committerIngo Molnar <mingo@kernel.org>2012-10-05 13:54:46 +0200
commit5f7865f3e44db4c73fdc454fb2af40806212a7ca (patch)
tree279a1f2588b875019c80e2ae779bd66bb6544137 /kernel
parent2b17c545a4cdbbbadcd7f1e9684c2d7db8f085a6 (diff)
downloadlinux-5f7865f3e44db4c73fdc454fb2af40806212a7ca.tar.gz
linux-5f7865f3e44db4c73fdc454fb2af40806212a7ca.tar.bz2
linux-5f7865f3e44db4c73fdc454fb2af40806212a7ca.zip
sched: Ensure 'sched_domains_numa_levels' is safe to use in other functions
We should temporarily reset 'sched_domains_numa_levels' to 0 after it is reset to 'level' in sched_init_numa(). If it fails to allocate memory for array sched_domains_numa_masks[][], the array will contain less then 'level' members. This could be dangerous when we use it to iterate array sched_domains_numa_masks[][] in other functions. This patch set sched_domains_numa_levels to 0 before initializing array sched_domains_numa_masks[][], and reset it to 'level' when sched_domains_numa_masks[][] is fully initialized. Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1348578751-16904-2-git-send-email-tangchen@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel')
-rw-r--r--kernel/sched/core.c13
1 files changed, 13 insertions, 0 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c17747236438..f895fdd32c5b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6122,6 +6122,17 @@ static void sched_init_numa(void)
* numbers.
*/
+ /*
+ * Here, we should temporarily reset sched_domains_numa_levels to 0.
+ * If it fails to allocate memory for array sched_domains_numa_masks[][],
+ * the array will contain less then 'level' members. This could be
+ * dangerous when we use it to iterate array sched_domains_numa_masks[][]
+ * in other functions.
+ *
+ * We reset it to 'level' at the end of this function.
+ */
+ sched_domains_numa_levels = 0;
+
sched_domains_numa_masks = kzalloc(sizeof(void *) * level, GFP_KERNEL);
if (!sched_domains_numa_masks)
return;
@@ -6176,6 +6187,8 @@ static void sched_init_numa(void)
}
sched_domain_topology = tl;
+
+ sched_domains_numa_levels = level;
}
#else
static inline void sched_init_numa(void)