On Tue, Mar 16, 2021 at 09:54:01AM -0400, Sasha Levin wrote: > On Tue, Mar 16, 2021 at 06:46:10AM +0100, gregkh@xxxxxxxxxxxxxxxxxxx wrote: > > On Mon, Mar 15, 2021 at 07:56:02PM +0000, Vladimir Oltean wrote: > > > +Andrew, Vivien, > > > > > > On Mon, Mar 15, 2021 at 02:53:26PM +0100, gregkh@xxxxxxxxxxxxxxxxxxx wrote: > > > > From: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > > > > > > > From: Vladimir Oltean <vladimir.oltean@xxxxxxx> > > > > > > > > [ Upstream commit a3b0b6479700a5b0af2c631cb2ec0fb7a0d978f2 ] > > > > > > > > At the moment, taggers are left with the task of ensuring that the skb > > > > headers are writable (which they aren't, if the frames were cloned for > > > > TX timestamping, for flooding by the bridge, etc), and that there is > > > > enough space in the skb data area for the DSA tag to be pushed. > > > > > > > > Moreover, the life of tail taggers is even harder, because they need to > > > > ensure that short frames have enough padding, a problem that normal > > > > taggers don't have. > > > > > > > > The principle of the DSA framework is that everything except for the > > > > most intimate hardware specifics (like in this case, the actual packing > > > > of the DSA tag bits) should be done inside the core, to avoid having > > > > code paths that are very rarely tested. > > > > > > > > So provide a TX reallocation procedure that should cover the known needs > > > > of DSA today. > > > > > > > > Note that this patch also gives the network stack a good hint about the > > > > headroom/tailroom it's going to need. Up till now it wasn't doing that. > > > > So the reallocation procedure should really be there only for the > > > > exceptional cases, and for cloned packets which need to be unshared. > > > > > > > > Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx> > > > > Tested-by: Christian Eggers <ceggers@xxxxxxx> # For tail taggers only > > > > Tested-by: Kurt Kanzenbach <kurt@xxxxxxxxxxxxx> > > > > Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx> > > > > Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx> > > > > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> > > > > --- > > > > > > For context, Sasha explains here: > > > https://www.spinics.net/lists/stable-commits/msg190151.html > > > (the conversation is somewhat truncated, unfortunately, because > > > stable-commits@xxxxxxxxxxxxxxx ate my replies) > > > that 13 patches were backported to get the unrelated commit 9200f515c41f > > > ("net: dsa: tag_mtk: fix 802.1ad VLAN egress") to apply cleanly with git-am. > > > > > > I am not strictly against this, even though I would have liked to know > > > that the maintainers were explicitly informed about it. > > > > > > Greg, could you make your stable backporting emails include the output > > > of ./get_maintainer.pl into the list of recipients? Thanks. > > > > I cc: everyone on the signed-off-by list on the patch, why would we need > > to add more? A maintainer should always be on that list automatically. > > Oh, hm, could this be an issue with subsystems that have a shared > maintainership model? In that scenario not all maintainers will sign-off > on a commit. So a shared maintainer trusts their co-maintainer for reviewing patches for Linus's tree and all future kernels, but NOT into an old backported stable tree? I doubt that, trust should be the same for both. thanks, greg k-h
