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chore(fc-fork): bump firecracker submodule — retire dead v1 MAP_SHARED/Msync surface - #469
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…HARED/Msync surface Bumps third_party/firecracker d78c1dc1 -> 0e02b3a9 (cortexapps/firecracker#9), removing the dead v1 MAP_SHARED + Msync/MsyncAndState snapshot surface that was superseded by the v2 UFFD substrate and the v3 vmstate-only post-copy path. Nothing in engrams emits it (the host's SnapshotType is {Full, Diff}; there is no `shared` load param), and ADR 0045 D1 marked it for retirement. No change to src/vmm/src/snapshot/ and no SNAPSHOT_VERSION bump — byte-compatible with stock. This PR's CI (build-firecracker + the stock<->fork snapshot-compat test + the FC integration suite) is the authoritative end-to-end validation of the fork change. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_013EkVddad6rxeV6xFfovQ8x
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Paired with cortexapps/firecracker#9. Bumps
third_party/firecrackerd78c1dc1 → 0e02b3a9, removing the dead v1MAP_SHARED/Msyncsnapshot surface that was superseded by the v2 UFFD substrate + the v3 vmstate-only post-copy path.Why it's safe
SnapshotTypeis{Full, Diff}and there is nosharedload param (client.rs). ADR 0045 D1 marked it for retirement.snapshot_file(MAP_PRIVATE — its existing behavior).src/vmm/src/snapshot/and noSNAPSHOT_VERSIONbump — byte-compatible with stock (the fork's hard invariant, exercised bystock_fork_snapshot_compat).Validation
cargo check -p vmm(lib + tests) foraarch64-unknown-linux-muslclean.build-firecracker(real GNU target) + the stock↔fork snapshot-compat test + the FC integration suite run against the v1-removed fork.Merge cortexapps/firecracker#9 →
engram/live-migrationfirst, then this. If #9 is squash-merged (new SHA onengram/live-migration), re-pin this submodule bump to the merged SHA before merging. (The pinned0e02b3a9is currently the tip of the fork PR branch.)Follow-up #2 of two flagged after the substrate cleanup series (follow-up #1 = #468).
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