just a note,
On (01/24/17 15:02), Dan Streetman wrote:
[..]
> @@ -692,6 +702,15 @@ static int __zswap_param_set(const char *val, const
> struct kernel_param *kp,
> */
> list_add_tail_rcu(&pool->list, &zswap_pools);
> put_pool = pool;
> + } else if (!zswap_has_pool) {
> + /* if initial pool creation failed, and this pool creation also
> + * failed, maybe both compressor and zpool params were bad.
> + * Allow changing this param, so pool creation will succeed
> + * when the other param is changed. We already verified this
> + * param is ok in the zpool_has_pool() or crypto_has_comp()
> + * checks above.
> + */
> + ret = param_set_charp(s, kp);
> }
>
> spin_unlock(&zswap_pools_lock);
looks like there still GFP_KERNEL allocation from atomic section:
param_set_charp()->kmalloc_parameter()->kmalloc(GFP_KERNEL), under
`zswap_pools_lock'.
-ss
