Re: [PATCH v5 04/22] cachefiles: notify user daemon with anon_fd when looking up cookie

From: JeffleXu
Date: Mon Mar 21 2022 - 10:43:33 EST




On 3/21/22 10:01 PM, David Howells wrote:
> Jeffle Xu <jefflexu@xxxxxxxxxxxxxxxxx> wrote:
>
>> + read_lock(&cache->reqs_lock);
>> +
>> + /* recheck dead state under lock */
>> + if (test_bit(CACHEFILES_DEAD, &cache->flags)) {
>> + read_unlock(&cache->reqs_lock);
>> + ret = -EIO;
>> + goto out;
>> + }
>> +
>> + xa_lock(xa);
>> + ret = __xa_alloc(xa, &id, req, xa_limit_32b, GFP_KERNEL);
>
> You're holding a spinlock. You can't use GFP_KERNEL.

Oh yes... I've dropped into this for second time... Sorry for that.

>
>> +static int cachefiles_ondemand_cinit(struct cachefiles_cache *cache, char *args)
>> +{
>> ...
>> + tmp = kstrdup(args, GFP_KERNEL);
>
> No need to copy the string. The caller already did that and added a NUL for
> good measure.

Right.


>
> I would probably move most of the functions added in this patch to
> fs/cachefiles/ondemand.c.

Alright.


--
Thanks,
Jeffle