diff options
-rw-r--r-- | include/linux/cpumask.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index b24ac56477b4..4f7a63237471 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -617,6 +617,20 @@ static inline size_t cpumask_size(void) * ... use 'tmpmask' like a normal struct cpumask * ... * * free_cpumask_var(tmpmask); + * + * + * However, one notable exception is there. alloc_cpumask_var() allocates + * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has + * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t. + * + * cpumask_var_t tmpmask; + * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) + * return -ENOMEM; + * + * var = *tmpmask; + * + * This code makes NR_CPUS length memcopy and brings to a memory corruption. + * cpumask_copy() provide safe copy functionality. */ #ifdef CONFIG_CPUMASK_OFFSTACK typedef struct cpumask *cpumask_var_t; |