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    SubjectRe: [PATCH] Periodically flow expire from flow offload tables
    On Wed, Oct 26, 2022 at 09:40:11PM +0200, Michael Lilja wrote:
    > Hi,
    >
    > I just quickly tried following the flow_offload_teardown() path instead of clearing IPS_OFFLOAD in flow_offload_del() and it does have some side effects. The flow is added again before the HW has actually reported it to be NF_FLOW_HW_DEAD.
    >
    > The sequence with my patch is:
    > : Retire -> Remove from hw tables -> Remove from sw tables -> kfree(flow) -> flow_offload_add()
    >
    > But if flow_offload_teardown() is called on expire I see:
    > : Retire -> Remove from hw tables -> flow_offload_add() -> Remove from sw tables -> kfree(flow)
    >
    > I need to investigate why this happens, maybe the IPS_OFFLOAD flag is cleared too early and should not be cleared until the flow is actually removed, like I do? Maybe the issue is not seen before because on timeout or flow_is_dying() no packet arrive to create the flow again prematurely?

    Hm, IPS_OFFLOAD should be cleared from flow_offload_del() then, it is
    cleared too early.

    I'll post a fix for nf.git first then I propose to follow up on this
    flowtable feature. I'll keep you on Cc.

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