Re: [PATCH net] devlink: Remove extra assertion from flash notification logic

[Leon Romanovsky]

On Mon, Nov 15, 2021 at 10:14:37AM -0800, Jakub Kicinski wrote:
> On Mon, 15 Nov 2021 20:07:47 +0200 Leon Romanovsky wrote:
> > From: Leon Romanovsky <leonro@xxxxxxxxxx>
> > 
> > The mlxsw driver calls to various devlink flash routines even before
> > users can get any access to the devlink instance itself. For example,
> > mlxsw_core_fw_rev_validate() one of such functions.
> > 
> > It causes to the WARN_ON to trigger warning about devlink not
> > registered, while the flow is valid.
> 
> So the fix is to remove the warning and keep generating notifications
> about objects which to the best understanding of the user space do not
> exist?

If we delay this mlxsw specific notification, the user will get
DEVLINK_CMD_FLASH_UPDATE and DEVLINK_CMD_FLASH_UPDATE_END at the
same time. I didn't like this, probably users won't like it either,
so decided to go with less invasive solution as possible.

Thanks

> 
> > diff --git a/net/core/devlink.c b/net/core/devlink.c
> > index 5ba4f9434acd..6face738b16a 100644
> > --- a/net/core/devlink.c
> > +++ b/net/core/devlink.c
> > @@ -4229,7 +4229,6 @@ static void __devlink_flash_update_notify(struct devlink *devlink,
> >  	WARN_ON(cmd != DEVLINK_CMD_FLASH_UPDATE &&
> >  		cmd != DEVLINK_CMD_FLASH_UPDATE_END &&
> >  		cmd != DEVLINK_CMD_FLASH_UPDATE_STATUS);
> > -	WARN_ON(!xa_get_mark(&devlinks, devlink->index, DEVLINK_REGISTERED));
> >  
> >  	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> >  	if (!msg)
>