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fix(vmm): turn PCI hotplug off by default and require it off for GPU passthrough - #1387
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…passthrough QEMU emits ACPI hotplug AML for pcie-root-port buses when PCI hotplug is on, and qemu-acpi does not model it, so a TDX CVM with GPUs or NVSwitches on root ports failed lite verification with an ACPI digest mismatch. Rather than modeling that AML (#1203), require hotplug off for such topologies: MachineConfig::validate rejects them with a named error, and the VMM config, dstackup template, tutorial and e2e config default qemu_hotplug_off to true. The GPU goldens move to hotplug off, with hashes checked against the pinned QEMU reference image.
# Conflicts: # CHANGELOG.md
kvinwang
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… parser bounds #1387 requires PCI hotplug off for GPU passthrough, so the matrix GPU row failed; measure it with hotplug off and assert the named rejection without. #1229 reads XLF bit 1, not bit 6, for the initrd ceiling: fix the harness oracle and add a row with a 5-level-only kernel. #1367 made diagnose honour num_nics, num_verity_volumes and swtpm; compare it with measure. Run the new dstack-mr and dstack-types bound vectors from #1229, #1231, #1236 and Signed-off-by: Kevin Wang <wy721@qq.com> #1275 by exact name.
source-c
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Dstack-TEE#1387 made the VMM default qemu_hotplug_off to true and made ACPI generation reject hotplug with GPU root ports, but left the CLI defaulting to false. A measurement of a default VMM CVM therefore came out wrong, and one with GPUs failed with HotplugWithRootPorts, unless --hotplug-off true was passed. Signed-off-by: Kevin Wang <wy721@qq.com>
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Replaces #1203.
With PCI hotplug on, QEMU emits ACPI hotplug AML for every
pcie-root-portbus, whichqemu-acpidoes not model. A TDX CVM with GPUs or NVSwitches on root ports therefore failed lite verification with an ACPI digest mismatch (seen on an 8×B200 host).Instead of modeling that AML, require hotplug off:
MachineConfig::validaterejects hotplug with root-port passthrough (HotplugWithRootPorts), so the verifier, KMS anddstack-mrfail with a named error instead of a digest mismatch.qemu_hotplug_offdefaults totrueinvmm.toml, the dstackup template, the VMM tutorial and the full-stack e2e config.Breaking for hosts relying on the default: every CVM gets different ACPI tables, and so different RTMRs, on its next start. Anything pinning those measurements, such as the KMS aggregated-MR allowlist, needs updating. A host without GPUs can set
qemu_hotplug_off = falseto keep its current measurements.Verification
kvin/dstack-acpi-tables@sha256:54e692d8…) byte for byte.differential-random.pyagainst that image: 61/61 pass (29 fixed cases plus 32 random).cargo test -p qemu-acpi -p dstack-mr -p dstack-mr-cli -p dstack-verifier -p dstack-kms -p dstack-vmm -p dstack-cli-core: pass.cargo fmt --checkandclippy -D warningsare clean.