Re: [PATCH] net: qualcomm: rmnet: Allow partial updates of IFLA_FLAGS

From: subashab
Date: Thu Apr 22 2021 - 19:28:35 EST


On 2021-04-22 12:29, Alex Elder wrote:
On 4/22/21 1:20 PM, Bjorn Andersson wrote:
The idiomatic way to handle the changelink flags/mask pair seems to be
allow partial updates of the driver's link flags. In contrast the rmnet
driver masks the incoming flags and then use that as the new flags.

Change the rmnet driver to follow the common scheme, before the
introduction of IFLA_RMNET_FLAGS handling in iproute2 et al.

I like this a lot. It should have been implemented this way
to begin with; there's not much point to have the mask if
it's only applied to the passed-in value.

KS, are you aware of *any* existing user space code that
would not work correctly if this were accepted?

I.e., the way it was (is), the value passed in *assigns*
the data format flags. But with Bjorn's changes, the
data format flags would be *updated* (i.e., any bits not
set in the mask field would remain with their previous
value).

Reviewed-by: Alex Elder <elder@xxxxxxxxxx>

What rmnet functionality which was broken without this change.
That doesnt seem to be listed in this patch commit text.

If this is an enhancement, then patch needs to be targeted to net-next
instead of net