Add support for SEV-SNP

This bug is awaiting verification that the linux-gcp/5.15.0-1028.35 kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-needed-jammy' to 'verification-done-jammy'. If the problem still exists, change the tag 'verification-needed-jammy' to 'verification-failed-jammy'.

If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.

See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Thank you!

This bug was fixed in the package linux-gcp - 5.15.0-1029.36

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linux-gcp (5.15.0-1029.36) jammy; urgency=medium

  * jammy/linux-gcp: 5.15.0-1029.36 -proposed tracker (LP: #2003429)

  [ Ubuntu: 5.15.0-60.66 ]

  * jammy/linux: 5.15.0-60.66 -proposed tracker (LP: #2003450)
  * Revoke & rotate to new signing key (LP: #2002812)
    - [Packaging] Revoke and rotate to new signing key

linux-gcp (5.15.0-1028.35) jammy; urgency=medium

  * jammy/linux-gcp: 5.15.0-1028.35 -proposed tracker (LP: #2001767)

  * Add support for SEV-SNP (LP: #2001605)
    - KVM: SVM: Define sev_features and vmpl field in the VMSA
    - KVM: SEV: Refactor out sev_es_state struct
    - KVM: SVM: Create a separate mapping for the SEV-ES save area
    - KVM: SVM: Create a separate mapping for the GHCB save area
    - KVM: SVM: Update the SEV-ES save area mapping
    - x86/boot: Introduce helpers for MSR reads/writes
    - x86/boot: Use MSR read/write helpers instead of inline assembly
    - SAUCE: x86/compressed/64: Detect/setup SEV/SME features earlier in boot
    - x86/sev: Detect/setup SEV/SME features earlier in boot
    - x86/sev: Use CC_ATTR attribute to generalize string I/O unroll
    - x86/mm: Extend cc_attr to include AMD SEV-SNP
    - x86/sev: Shorten GHCB terminate macro names
    - SAUCE: x86/sev: Define the Linux specific guest termination reasons
    - x86/sev: Save the negotiated GHCB version
    - x86/sev: Carve out HV call's return value verification
    - x86/sev: Expose sev_es_ghcb_hv_call() for use by HyperV
    - x86/sev: Check SEV-SNP features support
    - x86/sev: Add a helper for the PVALIDATE instruction
    - x86/sev: Check the vmpl level
    - x86/compressed: Add helper for validating pages in the decompression stage
    - x86/compressed: Register GHCB memory when SEV-SNP is active
    - x86/sev: Register GHCB memory when SEV-SNP is active
    - x86/sev: Rename mem_encrypt.c to mem_encrypt_amd.c
    - x86/sev: Add helper for validating pages in early enc attribute changes
    - treewide: Replace the use of mem_encrypt_active() with cc_platform_has()
    - x86/head64: Carve out the guest encryption postprocessing into a helper
    - SAUCE: x86/kernel: Make the .bss..decrypted section shared in RMP table
    - x86/kernel: Validate ROM memory before accessing when SEV-SNP is active
    - SAUCE: x86/mm: Add support to validate memory when changing C-bit
    - x86/sev: Remove do_early_exception() forward declarations
    - x86/sev: Use SEV-SNP AP creation to start secondary CPUs
    - x86/head/64: Re-enable stack protection
    - x86/compressed/acpi: Move EFI detection to helper
    - x86/compressed/acpi: Move EFI system table lookup to helper
    - x86/compressed/acpi: Move EFI config table lookup to helper
    - x86/compressed/acpi: Move EFI vendor table lookup to helper
    - x86/compressed/acpi: Move EFI kexec handling into common code
    - x86/boot: Add Confidential Computing type to setup_data
    - KVM: x86: Move lookup of indexed CPUID leafs to helper
    - x86/sev: Move MSR-based VMGEXITs for CPUID to helper
    - x86/compressed/64: Add support for SEV-SNP CPUID table in #VC handlers
    - x86/boot: Add a pointer to Confident...