I believe this bug is not a regression because the sev-guest module has been missing since our initial implementation. We've observed this issue consistently from the beginning of our attestation workflow testing, rather than it appearing after an update or version change. The problem has been present from the start, indicating it's an original issue rather than functionality that previously worked and then broke.
We couldn't find any prior kernel version with the working sev-guest module based on our previous tests from the kernel 6.12+ version -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/2119148 Title: sev-guest kernel module not included in kernel package for SNP QEMU guests Status in linux package in Ubuntu: Incomplete Bug description: Environment: Distribution: Ubuntu Plucky Platform: SNP-enabled QEMU guest Kernel: 6.14.0-27-generic Issue: Guest attestation functionality is broken due to the absence of the sev-guest kernel module in the kernel package. This prevents proper operation of SNP (Secure Nested Paging) attestation features within Ubuntu Plucky guests running on SNP-enabled QEMU. Impact: Guest attestation process fails completely SNP security features are non-functional Tools like virtee/snpguest cannot perform attestation operations on Ubuntu Plucky Release Error Details: We observe the following issue during generation of SNP guest report on QEMU guest using virtee/snpguest tool: root@localhost:~# snpguest report attestation-report.bin random-request-data.txt --random ERROR: unable to open /dev/sev-guest because: No such file or directory (os error 2) When attempting to manually load the sev-guest module on QEMU guest, we see the following issue: root@localhost:~# modprobe sev-guest modprobe: FATAL: Module sev-guest not found in directory /lib/modules/6.14.0-27-generic Expected Behavior: The sev-guest kernel module should be included in the kernel package and available for loading to enable proper SNP guest attestation functionality. Actual Behavior: The sev-guest module is missing from the kernel/kernel module package, preventing SNP attestation features from working. QEMU CLI used for SNP Guest(Ubuntu Plucky version) launch: qemu-system-x86_64 \ -enable-kvm \ -cpu EPYC-v4 \ -nographic \ -machine memory-encryption=sev0 \ -object memory-backend-memfd,id=ram1,size=4096M \ -machine memory-backend=ram1 \ -object sev-snp-guest,id=sev0,cbitpos=51,reduced-phys-bits=1,kernel-hashes=on \ -bios OVMF.amdsev.fd \ -kernel guest-ubuntu-plucky.efi virtee/snpguest tool link: https://github.com/virtee/snpguest.git Regular SNP Guest Attestation Process Link: https://github.com/virtee/snpguest/tree/main?tab=readme-ov-file#regular-attestation-flowchart ProblemType: Bug DistroRelease: Ubuntu 25.04 Package: linux-modules-6.14.0-27-generic 6.14.0-27.27 ProcVersionSignature: Ubuntu 6.14.0-27.27-generic 6.14.6 Uname: Linux 6.14.0-27-generic x86_64 AlsaDevices: total 0 crw-rw---- 1 root audio 116, 1 Jul 30 18:36 seq crw-rw---- 1 root audio 116, 33 Jul 30 18:36 timer AplayDevices: Error: [Errno 2] No such file or directory: 'aplay' ApportVersion: 2.32.0-0ubuntu5.3 Architecture: amd64 ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord' AudioDevicesInUse: Error: [Errno 2] No such file or directory: 'fuser' CRDA: N/A CasperMD5CheckResult: unknown Date: Wed Jul 30 18:52:33 2025 Dependencies: Lspci: Error: [Errno 2] No such file or directory: 'lspci' Lspci-vt: Error: [Errno 2] No such file or directory: 'lspci' Lsusb: Error: [Errno 2] No such file or directory: 'lsusb' Lsusb-t: Error: [Errno 2] No such file or directory: 'lsusb' Lsusb-v: Error: [Errno 2] No such file or directory: 'lsusb' MachineType: QEMU Standard PC (i440FX + PIIX, 1996) PciMultimedia: ProcEnviron: PATH=(custom, no user) SHELL=/bin/bash TERM=vt220 ProcFB: 0 simpledrmdrmfb ProcKernelCmdLine: console=ttyS0 RelatedPackageVersions: linux-restricted-modules-6.14.0-27-generic N/A linux-backports-modules-6.14.0-27-generic N/A linux-firmware N/A RfKill: Error: [Errno 2] No such file or directory: 'rfkill' SourcePackage: linux UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 11/17/2024 dmi.bios.release: 0.0 dmi.bios.vendor: EDK II dmi.bios.version: edk2-20241117-5.fc41 dmi.chassis.type: 1 dmi.chassis.vendor: QEMU dmi.chassis.version: pc-i440fx-9.1 dmi.modalias: dmi:bvnEDKII:bvredk2-20241117-5.fc41:bd11/17/2024:br0.0:svnQEMU:pnStandardPC(i440FX+PIIX,1996):pvrpc-i440fx-9.1:cvnQEMU:ct1:cvrpc-i440fx-9.1:sku: dmi.product.name: Standard PC (i440FX + PIIX, 1996) dmi.product.version: pc-i440fx-9.1 dmi.sys.vendor: QEMU To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2119148/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
