Re: [PATCH] prestera: fix fallback to previous version on same major version

[Jesse Brandeburg]

On 8/2/2023 2:23 AM, Jonas Gorski wrote:
> When both supported and previous version have the same major version,
> and the firmwares are missing, the driver ends in a loop requesting the
> same (previous) version over and over again:
> 
>     [   76.327413] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.1.img firmware, fall-back to previous 4.0 version
>     [   76.339802] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.0.img firmware, fall-back to previous 4.0 version
>     [   76.352162] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.0.img firmware, fall-back to previous 4.0 version
>     [   76.364502] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.0.img firmware, fall-back to previous 4.0 version
>     [   76.376848] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.0.img firmware, fall-back to previous 4.0 version
>     [   76.389183] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.0.img firmware, fall-back to previous 4.0 version
>     [   76.401522] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.0.img firmware, fall-back to previous 4.0 version
>     [   76.413860] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.0.img firmware, fall-back to previous 4.0 version
>     [   76.426199] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.0.img firmware, fall-back to previous 4.0 version
>     ...
> 
> Fix this by inverting the check to that we aren't yet at the previous
> version, and also check the minor version.
> 
> This also catches the case where both versions are the same, as it was
> after commit bb5dbf2cc64d ("net: marvell: prestera: add firmware v4.0
> support").
> 
> With this fix applied:
> 
>     [   88.499622] Prestera DX 0000:01:00.0: missing latest mrvl/prestera/mvsw_prestera_fw-v4.1.img firmware, fall-back to previous 4.0 version
>     [   88.511995] Prestera DX 0000:01:00.0: failed to request previous firmware: mrvl/prestera/mvsw_prestera_fw-v4.0.img
>     [   88.522403] Prestera DX: probe of 0000:01:00.0 failed with error -2
> 
> Fixes: 47f26018a414 ("net: marvell: prestera: try to load previous fw version")
> Signed-off-by: Jonas Gorski <jonas.gorski@xxxxxxxx>

Reviewed-by: Jesse Brandeburg <jesse.brandeburg@xxxxxxxxx>