Re: [PATCH net-next v7 4/5] net: rnpgbe: Add basic mbx_fw support

From: Yibo Dong
Date: Fri Aug 22 2025 - 02:55:46 EST


On Fri, Aug 22, 2025 at 06:07:51AM +0000, Parthiban.Veerasooran@xxxxxxxxxxxxx wrote:
> On 22/08/25 11:07 am, Yibo Dong wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> >
> > On Fri, Aug 22, 2025 at 04:49:44AM +0000, Parthiban.Veerasooran@xxxxxxxxxxxxx wrote:
> >> On 22/08/25 8:04 am, Dong Yibo wrote:
> >>> +/**
> >>> + * mucse_mbx_get_capability - Get hw abilities from fw
> >>> + * @hw: pointer to the HW structure
> >>> + *
> >>> + * mucse_mbx_get_capability tries to get capabities from
> >>> + * hw. Many retrys will do if it is failed.
> >>> + *
> >>> + * @return: 0 on success, negative on failure
> >>> + **/
> >>> +int mucse_mbx_get_capability(struct mucse_hw *hw)
> >>> +{
> >>> + struct hw_abilities ability = {};
> >>> + int try_cnt = 3;
> >>> + int err = -EIO;
> >> Here too you no need to assign -EIO as it is updated in the while.
> >>
> >> Best regards,
> >> Parthiban V
> >>> +
> >>> + while (try_cnt--) {
> >>> + err = mucse_fw_get_capability(hw, &ability);
> >>> + if (err)
> >>> + continue;
> >>> + hw->pfvfnum = le16_to_cpu(ability.pfnum) & GENMASK_U16(7, 0);
> >>> + return 0;
> >>> + }
> >>> + return err;
> >>> +}
> >>> +
> >
> > err is updated because 'try_cnt = 3'. But to the code logic itself, it should
> > not leave err uninitialized since no guarantee that codes 'whthin while'
> > run at least once. Right?
> Yes, but 'try_cnt' is hard coded as 3, so the 'while loop' will always
> execute and err will definitely be updated.
>
> So in this case, the check isn’t needed unless try_cnt is being modified
> externally with unknown values, which doesn’t seem to be happening here.
>
> Best regards,
> Parthiban V
> >
> > Thanks for your feedback.
> >
> >
>

Is it fine if I add some comment like this?
.....
/* Initialized as a defensive measure to handle edge cases
* where try_cnt might be modified
*/
int err = -EIO;
.....

Additionally, keeping this initialization ensures we’ll no need to consider
its impact every time 'try_cnt' is modified (Although this situation is
almost impossible).

Thanks for your feedback.