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Subject: Re: [PATCH -next] RDMA/mlx5: fix type warning of sizeof in
 __mlx5_ib_alloc_counters()
To:     Leon Romanovsky <leon@kernel.org>, Jason Gunthorpe <jgg@ziepe.ca>
References: <20200917082926.GA869610@unreal>
 <20200917091008.2309158-1-liushixin2@huawei.com>
 <20200917090810.GB869610@unreal> <20200917123806.GA114613@nvidia.com>
 <20200917170511.GI869610@unreal> <20200917172451.GK8409@ziepe.ca>
 <20200917173346.GK869610@unreal>
CC:     Doug Ledford <dledford@redhat.com>, <linux-rdma@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
From:   Liu Shixin <liushixin2@huawei.com>
Message-ID: <59dfb43f-04a7-b02a-1619-81d92ca69278@huawei.com>
Date:   Fri, 18 Sep 2020 11:23:18 +0800
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On 2020/9/18 1:33, Leon Romanovsky wrote:
> On Thu, Sep 17, 2020 at 02:24:51PM -0300, Jason Gunthorpe wrote:
>> On Thu, Sep 17, 2020 at 08:05:11PM +0300, Leon Romanovsky wrote:
>>> On Thu, Sep 17, 2020 at 09:38:06AM -0300, Jason Gunthorpe wrote:
>>>> On Thu, Sep 17, 2020 at 12:08:10PM +0300, Leon Romanovsky wrote:
>>>>> On Thu, Sep 17, 2020 at 05:10:08PM +0800, Liu Shixin wrote:
>>>>>> sizeof() when applied to a pointer typed expression should give the
>>>>>> size of the pointed data, even if the data is a pointer.
>>>>>>
>>>>>> Signed-off-by: Liu Shixin <liushixin2@huawei.com>
>>>> Needs a fixes line
>>>>
>>>>>>  	if (!cnts->names)
>>>>>>  		return -ENOMEM;
>>>>>>
>>>>>>  	cnts->offsets = kcalloc(num_counters,
>>>>>> -				sizeof(cnts->offsets), GFP_KERNEL);
>>>>>> +				sizeof(*cnts->offsets), GFP_KERNEL);
>>>>> This is not.
>>>> Why not?
>>> cnts->offsets is array of pointers that we will set later.
>>> The "sizeof(*cnts->offsets)" will return the size of size_t, while we
>>> need to get "size_t *".
>> Then why isn't a pointer to size **?
>>
>> Something is rotten here
> No problem, I'll check.
I think cnts->offsets is an array pointer whose element is size_t rathen than pointer,
so the patch description does not correspond.
And I think it should be modified to sizeof(*cnts->offsets) with other description.
>
>> Jason
> .
>