Re: [PATCH net-next RFC 02/13] devlink: Add reload levels data to dev get

[Moshe Shemesh]

On 7/28/2020 3:58 AM, Jakub Kicinski wrote:
> On Mon, 27 Jul 2020 14:02:22 +0300 Moshe Shemesh wrote:
> > Expose devlink reload supported levels and driver's default level to the
> > user through devlink dev get command.
> >
> > Examples:
> > $ devlink dev show
> > pci/0000:82:00.0:
> >    reload_levels_info:
> >      default_level driver
> >      supported_levels:
> >        driver fw_reset fw_live_patch
> > pci/0000:82:00.1:
> >    reload_levels_info:
> >      default_level driver
> >      supported_levels:
> >        driver fw_reset fw_live_patch
> >
> > $ devlink dev show -jp
> > {
> >      "dev": {
> >          "pci/0000:82:00.0": {
> >              "reload_levels_info": {
> >                  "default_level": "driver",
> >                  "supported_levels": [ "driver","fw_reset","fw_live_patch" ]
> >              }
> >          },
> >          "pci/0000:82:00.1": {
> >              "reload_levels_info": {
> >                  "default_level": "driver",
> >                  "supported_levels": [ "driver","fw_reset","fw_live_patch" ]
> >              }
> >          }
> >      }
> > }
> >
> > Signed-off-by: Moshe Shemesh <moshe@xxxxxxxxxxxx>
> The fact that the driver supports fw_live_patch, does not necessarily
> mean that the currently running FW can be live upgraded to the
> currently flashed one, right?


That's correct, though the feature is supported, the firmware gap may 
not be suitable for live_patch.

The user will be noted accordingly by extack message.

> This interface does not appear to be optimal for the purpose.
>
> Again, documentation of what can be lost (in terms of configuration and
> features) upon upgrade is missing.


I will clarify in documentation. On live_patch nothing should be lost or 
re-initialized, that's the "live" thing.