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Message-ID: <3ee0dda3-d80b-4058-49e7-88ceb6426459@gmail.com>
Date:   Mon, 14 Mar 2022 17:25:43 +0530
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Subject: Re: [PATCH] staging: android: ashmem: Declared file operation with
 const keyword Warning found by checkpatch.pl script.
Content-Language: en-US
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Pavel Skripkin <paskripkin@gmail.com>,
        =?UTF-8?B?QXJ2ZSBIasO4bm5ldsOl?= =?UTF-8?Q?g?= <arve@android.com>,
        Todd Kjos <tkjos@android.com>,
        Martijn Coenen <maco@android.com>,
        Joel Fernandes <joel@joelfernandes.org>,
        Christian Brauner <brauner@kernel.org>,
        Hridya Valsaraju <hridya@google.com>,
        Suren Baghdasaryan <surenb@google.com>,
        linux-kernel@vger.kernel.org, linux-staging@lists.linux.dev
References: <20220312204128.3942-1-shaikhkamal2012@gmail.com>
 <303ed0c8-8e2c-51a4-a4da-be973a25cdec@gmail.com>
 <bf27518d-4990-8b0e-c6ea-26a658ce2e54@gmail.com> <Yi8oFtMxfTkPF8/h@kroah.com>
From:   shaikh kamaluddin <shaikhkamal2012@gmail.com>
In-Reply-To: <Yi8oFtMxfTkPF8/h@kroah.com>
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On 3/14/2022 5:03 PM, Greg Kroah-Hartman wrote:
> On Mon, Mar 14, 2022 at 04:55:55PM +0530, shaikh kamaluddin wrote:
>> On 3/13/2022 3:13 AM, Pavel Skripkin wrote:
>>> Hi Shaikh,
>>>
>>> On 3/12/22 23:41, shaikh kamal wrote:
>>>> Signed-off-by: shaikh kamal <shaikhkamal2012@gmail.com>
>>>> ---
>>>>    drivers/staging/android/ashmem.c | 2 +-
>>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/staging/android/ashmem.c
>>>> b/drivers/staging/android/ashmem.c
>>>> index ddbde3f8430e..4c6b420fbf4d 100644
>>>> --- a/drivers/staging/android/ashmem.c
>>>> +++ b/drivers/staging/android/ashmem.c
>>>> @@ -377,7 +377,7 @@ ashmem_vmfile_get_unmapped_area(struct file
>>>> *file, unsigned long addr,
>>>>    static int ashmem_mmap(struct file *file, struct vm_area_struct *vma)
>>>>    {
>>>> -    static struct file_operations vmfile_fops;
>>>> +    static const struct file_operations vmfile_fops;
>>>>        struct ashmem_area *asma = file->private_data;
>>>>        int ret = 0;
>>>
>>> Are you sure this patch compiles? vmfile_fops is overrided few lines below
>>>
>>> odd checkpatch.pl warning...
>>>
>>>
>>>
>>>
>>> With regards,
>>> Pavel Skripkin
>>
>> Thank you,yes vmfile_fops is overrided in below code.
>> Building the kernel - make -j4,
>> drivers/staging/android/ashmem.c: In function ‘ashmem_mmap’:
>> drivers/staging/android/ashmem.c:431:16: error: assignment of read-only
>> variable ‘vmfile_fops’
>>      vmfile_fops = *vmfile->f_op;
>>                  ^
>> drivers/staging/android/ashmem.c:432:21: error: assignment of member ‘mmap’
>> in read-only object
>>      vmfile_fops.mmap = ashmem_vmfile_mmap;
>>                       ^
>> drivers/staging/android/ashmem.c:433:34: error: assignment of member
>> ‘get_unmapped_area’ in read-only object
>>      vmfile_fops.get_unmapped_area =
>>                                    ^
>> scripts/Makefile.build:288: recipe for target
>> 'drivers/staging/android/ashmem.o' failed
>> make[3]: *** [drivers/staging/android/ashmem.o] Error 1
>> scripts/Makefile.build:550: recipe for target 'drivers/staging/android'
>> failed
>> make[2]: *** [drivers/staging/android] Error 2
>> scripts/Makefile.build:550: recipe for target 'drivers/staging' failed
>> make[1]: *** [drivers/staging] Error 2
>> Makefile:1831: recipe for target 'drivers' failed
> 
> As always, it is expected that when you submit a change to the kernel,
> at the very least you have test-built it to ensure that it does not
> break the build.  Please remember to do this next time.
> 
> thanks,
> 
> greg k-h


Thank you, I will do that.

Regards,
Shaikh Kamaluddin