Re: [Cake] [PATCH net-next] net/sched: fq_codel, cake: widen backlogs to u64

On Sat, Sep 26, 2026 at 11:43 AM Jamal Hadi Salim [off-list ref] wrote:

I am working on a v2 that drops at enqueue once the accounted backlog
crosses  (U32_MAX - QDISC_PKT_LEN_MAX), so no counter can wrap.
That is Eric's original suggestion which preserves the point you raised.

While looking at this closely for this update i noticed more qdiscs
which for different reasons also suffer from ((u64)backlog + len <=
limit idiom.
So far it's clear from bfifo, gred and plug are the only ones safe
because their limit is in bytes (as opposed to others which are packet
counting)

Eric: Unless i hear otherwise from you, the configurable byte ceiling
you mentioned (a good noun seems to be CONFIG_NET_SCH_BACKLOG_CEILING)
is a follow-up;

SGTM, thanks Jamal.