KVM/arm64 changes for 6.13, part #1

 - Support for stage-1 permission indirection (FEAT_S1PIE) and
   permission overlays (FEAT_S1POE), including nested virt + the
   emulated page table walker

 - Introduce PSCI SYSTEM_OFF2 support to KVM + client driver. This call
   was introduced in PSCIv1.3 as a mechanism to request hibernation,
   similar to the S4 state in ACPI

 - Explicitly trap + hide FEAT_MPAM (QoS controls) from KVM guests. As
   part of it, introduce trivial initialization of the host's MPAM
   context so KVM can use the corresponding traps

 - PMU support under nested virtualization, honoring the guest
   hypervisor's trap configuration and event filtering when running a
   nested guest

 - Fixes to vgic ITS serialization where stale device/interrupt table
   entries are not zeroed when the mapping is invalidated by the VM

 - Avoid emulated MMIO completion if userspace has requested synchronous
   external abort injection

 - Various fixes and cleanups affecting pKVM, vCPU initialization, and
   selftests

- Drop obsolete references to PPC970 KVM, which was removed 10 years ago.

- Fix incorrect references to non-existing ioctls

- List registers supported by KVM_GET/SET_ONE_REG on s390

- Use rST internal links

- Reorganize the introduction to the API document

KVM selftests changes for 6.13

 - Enable XFAM-based features by default for all selftests VMs, which will
   allow removing the "no AVX" restriction.

* kvm-arm64/mmio-sea:
  : Fix for SEA injection in response to MMIO
  :
  : Fix + test coverage for SEA injection in response to an unhandled MMIO
  : exit to userspace. Naturally, if userspace decides to abort an MMIO
  : instruction KVM shouldn't continue with instruction emulation...
  KVM: arm64: selftests: Add tests for MMIO external abort injection
  KVM: arm64: selftests: Convert to kernel's ESR terminology
  tools: arm64: Grab a copy of esr.h from kernel
  KVM: arm64: Don't retire aborted MMIO instruction

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

When freeing a VM, don't call into KVM to manually remove each memslot,
simply cleanup and free any userspace assets associated with the memory
region.  KVM is ultimately responsible for ensuring kernel resources are
freed when the VM is destroyed, deleting memslots one-by-one is
unnecessarily slow, and unless a test is already leaking the VM fd, the
VM will be destroyed when kvm_vm_release() is called.

Not deleting KVM's memslot also allows cleaning up dead VMs without having
to care whether or not the to-be-freed VM is dead or alive.

Reported-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Reported-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/kvmarm/Zy0bcM0m-N18gAZz@google.com/
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

In 08a7d2525511 ("tools arch x86: Sync the msr-index.h copy with the
kernel sources"), VMX_BASIC_MEM_TYPE_WB was removed.  Use X86_MEMTYPE_WB
instead.

Fixes: 08a7d2525511 ("tools arch x86: Sync the msr-index.h copy with the
kernel sources")
Signed-off-by: John Sperbeck <jsperbeck@google.com>
Message-ID: <20241106034031.503291-1-jsperbeck@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

To play nice with compilers generating AVX instructions, set CR4.OSXSAVE
and configure XCR0 by default when creating selftests vCPUs.  Some distros
have switched gcc to '-march=x86-64-v3' by default, and while it's hard to
find a CPU which doesn't support AVX today, many KVM selftests fail with

  ==== Test Assertion Failure ====
    lib/x86_64/processor.c:570: Unhandled exception in guest
    pid=72747 tid=72747 errno=4 - Interrupted system call
    Unhandled exception '0x6' at guest RIP '0x4104f7'

due to selftests not enabling AVX by default for the guest.  The failure
is easy to reproduce elsewhere with:

   $ make clean && CFLAGS='-march=x86-64-v3' make -j && ./x86_64/kvm_pv_test

E.g. gcc-13 with -march=x86-64-v3 compiles this chunk from selftests'
kvm_fixup_exception():

        regs->rip = regs->r11;
        regs->r9 = regs->vector;
        regs->r10 = regs->error_code;

into this monstronsity (which is clever, but oof):

  405313:       c4 e1 f9 6e c8          vmovq  %rax,%xmm1
  405318:       48 89 68 08             mov    %rbp,0x8(%rax)
  40531c:       48 89 e8                mov    %rbp,%rax
  40531f:       c4 c3 f1 22 c4 01       vpinsrq $0x1,%r12,%xmm1,%xmm0
  405325:       49 89 6d 38             mov    %rbp,0x38(%r13)
  405329:       c5 fa 7f 45 00          vmovdqu %xmm0,0x0(%rbp)

Alternatively, KVM selftests could explicitly restrict the compiler to
-march=x86-64-v2, but odds are very good that punting on AVX enabling will
simply result in tests that "need" AVX doing their own thing, e.g. there
are already three or so additional cleanups that can be done on top.

Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Closes: https://lore.kernel.org/all/20240920154422.2890096-1-vkuznets@redhat.com
Reviewed-and-tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Link: https://lore.kernel.org/r/20241003234337.273364-6-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

Drop the KVM selftests specific flavoring of ESR in favor of the kernel
header.

Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20241025203106.3529261-4-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>

Introduce new regression tests to verify the ASM inline block in the SORTL
and DFLTCC CPU subfunctions for the s390x architecture. These tests ensure
that future changes to the ASM code are properly validated.

The test procedure:

1. Create a VM and request the KVM_S390_VM_CPU_MACHINE_SUBFUNC attribute
   from the KVM_S390_VM_CPU_MODEL group for this VM. This SUBFUNC attribute
   contains the results of all CPU subfunction instructions.
2. For each tested subfunction (SORTL and DFLTCC), execute the
   corresponding ASM instruction and capture the result array.
3. Perform a memory comparison between the results stored in the SUBFUNC
   attribute (obtained in step 1) and the ASM instruction results (obtained
   in step 2) for each tested subfunction.

This process ensures that the KVM implementation accurately reflects the
behavior of the actual CPU instructions for the tested subfunctions.

Suggested-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Hariharan Mari <hari55@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
Link: https://lore.kernel.org/r/20240823130947.38323-2-hari55@linux.ibm.com
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Message-ID: <20240823130947.38323-2-hari55@linux.ibm.com>

KVM selftests changes for 6.12:

 - Fix a goof that caused some Hyper-V tests to be skipped when run on bare
   metal, i.e. NOT in a VM.

 - Add a regression test for KVM's handling of SHUTDOWN for an SEV-ES guest.

 - Explicitly include one-off assets in .gitignore.  Past Sean was completely
   wrong about not being able to detect missing .gitignore entries.

 - Verify userspace single-stepping works when KVM happens to handle a VM-Exit
   in its fastpath.

 - Misc cleanups