The patch titled
x86, numa: add error handling for bad cpu-to-node mappings
has been added to the -mm tree. Its filename is
x86-numa-add-error-handling-for-bad-cpu-to-node-mappings.patch
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------------------------------------------------------
Subject: x86, numa: add error handling for bad cpu-to-node mappings
From: David Rientjes <rientjes@xxxxxxxxxx>
CONFIG_DEBUG_PER_CPU_MAPS may return NUMA_NO_NODE when an
early_cpu_to_node() mapping hasn't been initialized. In such a case, it
emits a warning and continues without an issue but callers may try to use
the return value to index into an array.
We can catch those errors and fail silently since a warning has already
been emitted. No current user of numa_add_cpu() requires this error
checking to avoid a crash, but it's better to be proactive in case a
future user happens to have a bug and a user tries to diagnose it with
CONFIG_DEBUG_PER_CPU_MAPS.
Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx>
Reported-by: Jesper Juhl <jj@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/x86/mm/numa_64.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff -puN arch/x86/mm/numa_64.c~x86-numa-add-error-handling-for-bad-cpu-to-node-mappings arch/x86/mm/numa_64.c
--- a/arch/x86/mm/numa_64.c~x86-numa-add-error-handling-for-bad-cpu-to-node-mappings
+++ a/arch/x86/mm/numa_64.c
@@ -839,6 +839,10 @@ static struct cpumask __cpuinit *debug_c
struct cpumask *mask;
char buf[64];
+ if (node == NUMA_NO_NODE) {
+ /* early_cpu_to_node() already emits a warning and trace */
+ return NULL;
+ }
mask = node_to_cpumask_map[node];
if (!mask) {
pr_err("node_to_cpumask_map[%i] NULL\n", node);
@@ -877,6 +881,10 @@ static void __cpuinit numa_set_cpumask(i
struct cpumask *mask;
int i;
+ if (node == NUMA_NO_NODE) {
+ /* early_cpu_to_node() already emits a warning and trace */
+ return;
+ }
for_each_online_node(i) {
unsigned long addr;
_
Patches currently in -mm which might be from rientjes@xxxxxxxxxx are
origin.patch
linux-next.patch
x86-numa-add-error-handling-for-bad-cpu-to-node-mappings.patch
jbd-remove-dependency-on-__gfp_nofail.patch
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