Re: [PATCH RESEND v2 for-next 1/7] RDMA/hns: Fix potential compile warnings on hr_reg_write()

[liweihang <liweihang@huawei.com>]

On 2021/6/17 3:40, Jason Gunthorpe wrote:
> On Wed, Jun 02, 2021 at 04:57:39PM +0800, Weihang Li wrote:
>> From: Lang Cheng <chenglang@huawei.com>
>>
>> GCC may reports an running time assert error when a value calculated from
>> ib_mtu_enum_to_int() is using as 'val' in FIELD_PREDP:
>>
>> include/linux/compiler_types.h:328:38: error: call to
>> '__compiletime_assert_1524' declared with attribute error: FIELD_PREP:
>> value too large for the field
> 
> Huh? This warning looks reliable to me, you should not suppress it
> like this.
> 
>> But actually this error will still exists even if the driver can ensure
>> that ib_mtu_enum_to_int() returns a legal value. So add a mask in
>> hr_reg_write() to avoid above warning.
> 
> I think you need to have an if that ib_mtu_enum_to_int() is not
> negative, that should satisfy the CFA?
> 
> Jason
> 

I add a check for the integer mtu from ib_mtu_enum_to_int(), and gcc stop to
complain about that. I will add a patch to this series to fix it. Thank you.

Weihang