diff options
| -rw-r--r-- | arch/powerpc/mm/numa.c | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c index 30a42e24bf14..4ebbb9e99286 100644 --- a/arch/powerpc/mm/numa.c +++ b/arch/powerpc/mm/numa.c @@ -1591,6 +1591,20 @@ int arch_update_cpu_topology(void) cpu = cpu_last_thread_sibling(cpu); } + /* + * In cases where we have nothing to update (because the updates list + * is too short or because the new topology is same as the old one), + * skip invoking update_cpu_topology() via stop-machine(). This is + * necessary (and not just a fast-path optimization) since stop-machine + * can end up electing a random CPU to run update_cpu_topology(), and + * thus trick us into setting up incorrect cpu-node mappings (since + * 'updates' is kzalloc()'ed). + * + * And for the similar reason, we will skip all the following updating. + */ + if (!cpumask_weight(&updated_cpus)) + goto out; + stop_machine(update_cpu_topology, &updates[0], &updated_cpus); /* @@ -1612,6 +1626,7 @@ int arch_update_cpu_topology(void) changed = 1; } +out: kfree(updates); return changed; } |