Re: [PATCH v5 02/18] iommu: Implement IOMMU Live update FLB callbacks
From: Nicolin Chen
Date: Tue Oct 13 2026 - 18:49:30 EST
On Tue, Oct 13, 2026 at 08:57:05PM +0000, Samiullah Khawaja wrote:
> On Mon, Oct 12, 2026 at 05:25:42PM -0700, Nicolin Chen wrote:
> > Could incoming and outgoing objects exist in the same time?
> >
> > Correct me if I am wrong: I expect the lifecycle of an incoming
> > object will end once liveupdate completes, and the outgoing one
> > can only exist after that?
>
> LUO can have incoming and outgoing at the same time. The incoming FLB
> stays until all the sessions from the previous kernel that use it are
> finished, and the outgoing FLB is created when the first FD that uses it
> is preserved in the current kernel. So if a new preservation starts
> before all the incoming sessions are finished, both exist.
>
> Generally, it should be rare, as after the live update the userspace
> orchestrator (like systemd) would probably finish all the sessions. At
> the FD level it is mutually exclusive, but at the FLB level it is
> possible.
OK. It doesn't sound practically possible. Yet, fine if it's a
common practice to have separate objs for LUO.
Nicolin