Re: [GIT PULL] io_uring fix for 6.17-rc5

[Jens Axboe <axboe@kernel.dk>]

On 9/5/25 1:13 PM, Caleb Sander Mateos wrote:
> On Fri, Sep 5, 2025 at 12:04?PM Jens Axboe <axboe@kernel.dk> wrote:
>>
>> On 9/5/25 11:24 AM, Linus Torvalds wrote:
>>> On Fri, 5 Sept 2025 at 04:18, Jens Axboe <axboe@kernel.dk> wrote:
>>>>
>>>> Just a single fix for an issue with the resource node rewrite that
>>>> happened a few releases ago. Please pull!
>>>
>>> I've pulled this, but the commentary is strange, and the patch makes
>>> no sense to me, so I unpulled it again.
>>>
>>> Yes, it changes things from kvmalloc_array() to kvcalloc(). Fine.
>>>
>>> And yes, kvcalloc() clearly clears the resulting allocation. Also fine.
>>>
>>> But even in the old version, it used __GFP_ZERO.
>>>
>>> In fact, afaik the *ONLY* difference between kvcalloc() and
>>> kvmalloc_array() array is that kvcalloc() adds the __GFP_ZERO to the
>>> flags argument:
>>>
>>>    #define kvcalloc_node_noprof(_n,_s,_f,_node)  \
>>>       kvmalloc_array_node_noprof(_n,_s,(_f)|__GFP_ZERO,_node)
>>>
>>> so afaik, this doesn't actually fix anything at all.
>>
>> Agree, I think I was too hasty in queueing that up. I overlooked that we
>> already had __GFP_ZERO in there. On the road this week and tending to
>> these kinds of duties in between, my bad. Caleb??
> 
> Sorry, this is my fault. I misread the code, the __GFP_ZERO does
> ensure the correct behavior. kvcalloc() might more clearly indicate
> the intent, but there's no bug. Apologies for the hasty patch, and
> agree it can be dropped.

The fact that there isn't a bug in there in the first place is good
news, so no worries!

-- 
Jens Axboe