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Subject: Re: [PATCH v2 1/2] ARM: Fix some check warnings of tool sparse
From:   "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com>
To:     "Russell King (Oracle)" <linux@armlinux.org.uk>
CC:     <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>
References: <20221010095346.1957-1-thunder.leizhen@huawei.com>
 <20221010095346.1957-2-thunder.leizhen@huawei.com>
 <Y0RC213QSASPZekQ@shell.armlinux.org.uk>
 <3c8c29a8-a757-8f9d-23c6-d5790ce01611@huawei.com>
Message-ID: <60f181d5-4e1e-f45b-bc94-73ec5eebb4d0@huawei.com>
Date:   Thu, 13 Oct 2022 09:28:30 +0800
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On 2022/10/11 10:13, Leizhen (ThunderTown) wrote:
> 
> 
> On 2022/10/11 0:05, Russell King (Oracle) wrote:
>> On Mon, Oct 10, 2022 at 05:53:45PM +0800, Zhen Lei wrote:
>>> Fix the following warnings:
>>>  warning: incorrect type in initializer (different address spaces)
>>>     expected unsigned short [noderef] __user *register __p
>>>     got unsigned short [usertype] *
>>>  warning: cast removes address space '__user' of expression
>>
>> I have a general principle that not all warnings should be fixed,
>> especially when it comes to sparse.
> 
> OK, I got it.
> 
>>
>> The aim is not to get to zero warnings - it's to get to a point where
>> the code is correct, and plastering the code with __force casts means
>> it isn't correct - you're just masking the warning.
>>
>> So no, I really don't like this. And I really don't like seeing
>> __force being used in open code in casts.
> 
> OK, I will clear only the first warning and leave the second warning.

Sorry, Maybe I misunderstood. '__force casts' mentioned here may include
not only '(__force u16 *)', but also '(u16 __user *)'.

> 
>>
> 

-- 
Regards,
  Zhen Lei