Re: [RFC PATCH 0/3] liveupdate: Move to feature flags for LUO and memfd ABI compatibility
From: Sean Christopherson <seanjc@google.com>
Date: 2026-09-10 22:42:37
Also in:
kexec, kvm, kvmarm, linux-arch, linux-iommu, linux-mm, linux-pci, lkml
On Thu, Sep 10, 2026, Jason Gunthorpe wrote:
Sean's initial email was asking for strict never-break ABI compatability rules on top, and that is what I've been reacting to.
No, I was never asking for that. I think we just have a different interpretation of ABI, or rather are talking about different pieces of ABI. I am still asking for never-break serialization format compatibility, i.e. the more literal save/restore ABI. I'm not asking for full backwards/forwards compatibility across all kernels version, i.e. the higher level "kernel" ABI. To phrase things differently: I am a-ok if kernels are inherently incompatible because they fundamentally operate differently and/or support different features. I am not ok if we end up with incompatible kernels because the save/restore interfaces and payloads are poorly designed, lack abstraction, etc.