linux-stable.git/tools/testing/selftests/kvm/lib, branch linux-6.9.y

Merge tag 'kvm-x86-pmu-6.9' of https://github.com/kvm-x86/linux into HEAD

2024-03-11T14:41:09+00:00

KVM x86 PMU changes for 6.9:

 - Fix several bugs where KVM speciously prevents the guest from utilizing
   fixed counters and architectural event encodings based on whether or not
   guest CPUID reports support for the _architectural_ encoding.

 - Fix a variety of bugs in KVM's emulation of RDPMC, e.g. for "fast" reads,
   priority of VMX interception vs #GP, PMC types in architectural PMUs, etc.

 - Add a selftest to verify KVM correctly emulates RDMPC, counter availability,
   and a variety of other PMC-related behaviors that depend on guest CPUID,
   i.e. are difficult to validate via KVM-Unit-Tests.

 - Zero out PMU metadata on AMD if the virtual PMU is disabled to avoid wasting
   cycles, e.g. when checking if a PMC event needs to be synthesized when
   skipping an instruction.

 - Optimize triggering of emulated events, e.g. for "count instructions" events
   when skipping an instruction, which yields a ~10% performance improvement in
   VM-Exit microbenchmarks when a vPMU is exposed to the guest.

 - Tighten the check for "PMI in guest" to reduce false positives if an NMI
   arrives in the host while KVM is handling an IRQ VM-Exit.

Merge tag 'kvm-x86-selftests-6.9' of https://github.com/kvm-x86/linux into HEAD

2024-03-11T14:20:35+00:00

KVM selftests changes for 6.9:

 - Add macros to reduce the amount of boilerplate code needed to write "simple"
   selftests, and to utilize selftest TAP infrastructure, which is especially
   beneficial for KVM selftests with multiple testcases.

 - Add basic smoke tests for SEV and SEV-ES, along with a pile of library
   support for handling private/encrypted/protected memory.

 - Fix benign bugs where tests neglect to close() guest_memfd files.

KVM: riscv: selftests: Change vcpu_has_ext to a common function

2024-03-06T15:23:27+00:00

Move vcpu_has_ext to the processor.c and rename it to __vcpu_has_ext
so that other test cases can use it for vCPU extension check.

Signed-off-by: Haibo Xu 
Reviewed-by: Andrew Jones 
Signed-off-by: Anup Patel

KVM: riscv: selftests: Add guest helper to get vcpu id

2024-03-06T15:23:23+00:00

Add guest_get_vcpuid() helper to simplify accessing to per-cpu
private data. The sscratch CSR was used to store the vcpu id.

Signed-off-by: Haibo Xu 
Reviewed-by: Andrew Jones 
Signed-off-by: Anup Patel

KVM: riscv: selftests: Add exception handling support

2024-03-06T15:21:41+00:00

Add the infrastructure for guest exception handling in riscv selftests.
Customized handlers can be enabled by vm_install_exception_handler(vector)
or vm_install_interrupt_handler().

The code is inspired from that of x86/arm64.

Signed-off-by: Haibo Xu 
Reviewed-by: Andrew Jones 
Signed-off-by: Anup Patel

KVM: selftests: Add a basic SEV-ES smoke test

2024-02-29T00:39:55+00:00

Extend sev_smoke_test to also run a minimal SEV-ES smoke test so that it's
possible to test KVM's unique VMRUN=>#VMEXIT path for SEV-ES guests
without needing a full blown SEV-ES capable VM, which requires a rather
absurd amount of properly configured collateral.

Punt on proper GHCB and ucall support, and instead use the GHCB MSR
protocol to signal test completion.  The most important thing at this
point is to have _any_ kind of testing of KVM's __svm_sev_es_vcpu_run().

Cc: Tom Lendacky 
Cc: Michael Roth 
Cc: Peter Gonda 
Cc: Carlos Bilbao 
Tested-by: Carlos Bilbao 
Link: https://lore.kernel.org/r/20240223004258.3104051-12-seanjc@google.com
Signed-off-by: Sean Christopherson

KVM: selftests: Add library for creating and interacting with SEV guests

2024-02-29T00:39:52+00:00

Add a library/APIs for creating and interfacing with SEV guests, all of
which need some amount of common functionality, e.g. an open file handle
for the SEV driver (/dev/sev), ioctl() wrappers to pass said file handle
to KVM, tracking of the C-bit, etc.

Add an x86-specific hook to initialize address properties, a.k.a. the
location of the C-bit.  An arch specific hook is rather gross, but x86
already has a dedicated #ifdef-protected kvm_get_cpu_address_width() hook,
i.e. the ugliest code already exists.

Cc: Paolo Bonzini 
Cc: Sean Christopherson 
Cc: Vishal Annapurve 
Cc: Ackerly Tng 
cc: Andrew Jones 
Cc: Tom Lendacky 
Cc: Michael Roth 
Tested-by: Carlos Bilbao 
Originally-by: Michael Roth 
Signed-off-by: Peter Gonda 
Co-developed-by: Sean Christopherson 
Link: https://lore.kernel.org/r/20240223004258.3104051-9-seanjc@google.com
Signed-off-by: Sean Christopherson

KVM: selftests: Allow tagging protected memory in guest page tables

2024-02-29T00:39:49+00:00

Add support for tagging and untagging guest physical address, e.g. to
allow x86's SEV and TDX guests to embed shared vs. private information in
the GPA.  SEV (encryption, a.k.a. C-bit) and TDX (shared, a.k.a. S-bit)
steal bits from the guest's physical address space that is consumed by the
CPU metadata, i.e. effectively aliases the "real" GPA.

Implement generic "tagging" so that the shared vs. private metadata can be
managed by x86 without bleeding too many details into common code.

Cc: Paolo Bonzini 
Cc: Sean Christopherson 
Cc: Vishal Annapurve 
Cc: Ackerly Tng 
cc: Andrew Jones 
Cc: Tom Lendacky 
Cc: Michael Roth 
Tested-by: Carlos Bilbao 
Originally-by: Michael Roth 
Signed-off-by: Peter Gonda 
Link: https://lore.kernel.org/r/20240223004258.3104051-8-seanjc@google.com
Signed-off-by: Sean Christopherson

KVM: selftests: Explicitly ucall pool from shared memory

2024-02-28T20:58:13+00:00

Allocate the common ucall pool using vm_vaddr_alloc_shared() so that the
ucall structures will be placed in shared (unencrypted) memory for VMs
with support for protected (encrypted) memory, e.g. x86's SEV.

Cc: Paolo Bonzini 
Cc: Sean Christopherson 
Cc: Vishal Annapurve 
Cc: Ackerly Tng 
cc: Andrew Jones 
Cc: Tom Lendacky 
Cc: Michael Roth 
Tested-by: Carlos Bilbao 
Signed-off-by: Peter Gonda 
[sean: massage changelog]
Link: https://lore.kernel.org/r/20240223004258.3104051-7-seanjc@google.com
Signed-off-by: Sean Christopherson

KVM: selftests: Add support for protected vm_vaddr_* allocations

2024-02-28T20:58:13+00:00

Test programs may wish to allocate shared vaddrs for things like
sharing memory with the guest. Since protected vms will have their
memory encrypted by default an interface is needed to explicitly
request shared pages.

Implement this by splitting the common code out from vm_vaddr_alloc()
and introducing a new vm_vaddr_alloc_shared().

Cc: Paolo Bonzini 
Cc: Sean Christopherson 
Cc: Vishal Annapurve 
Cc: Ackerly Tng 
cc: Andrew Jones 
Cc: Tom Lendacky 
Cc: Michael Roth 
Reviewed-by: Itaru Kitayama 
Tested-by: Carlos Bilbao 
Signed-off-by: Michael Roth 
Signed-off-by: Peter Gonda 
Link: https://lore.kernel.org/r/20240223004258.3104051-6-seanjc@google.com
Signed-off-by: Sean Christopherson