Revert "KVM: selftests: Fix nested SVM tests when built with clang"

Revert back to using memset() in generic_svm_setup() now that KVM
selftests override memset() and friends specifically to prevent the
compiler from generating fancy code and/or linking to the libc
implementation.

This reverts commit ed290e1c20da19fa100a3e0f421aa31b65984960.

Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220928233652.783504-8-seanjc@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Use kvm_cpu_has() for nested SVM checks

Use kvm_cpu_has() to check for nested SVM support, and drop the helpers
now that their functionality is trivial to implement.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20220614200707.3315957-6-seanjc@google.com

KVM: selftests: Add TEST_REQUIRE macros to reduce skipping copy+paste

Add TEST_REQUIRE() and __TEST_REQUIRE() to replace the myriad open coded
instances of selftests exiting with KSFT_SKIP after printing an
informational message. In addition to reducing the amount of boilerplate
code in selftests, the UPPERCASE macro names make it easier to visually
identify a test's requirements.

Convert usage that erroneously uses something other than print_skip()
and/or "exits" with '0' or some other non-KSFT_SKIP value.

Intentionally drop a kvm_vm_free() in aarch64/debug-exceptions.c as part
of the conversion. All memory and file descriptors are freed on process
exit, so the explicit free is superfluous.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Get rid of kvm_util_internal.h

Fold kvm_util_internal.h into kvm_util_base.h, i.e. make all KVM utility
stuff "public". Hiding struct implementations from tests has been a
massive failure, as it has led to pointless and poorly named wrappers,
unnecessarily opaque code, etc...

Not to mention that the approach was a complete failure as evidenced by
the non-zero number of tests that were including kvm_util_internal.h.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: nSVM: Set up MSR-Bitmap for SVM guests

Similar to VMX, allocate memory for MSR-Bitmap and fill in 'msrpm_base_pa'
in VMCB. To use it, tests will need to set INTERCEPT_MSR_PROT interception
along with the required bits in the MSR-Bitmap.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20220203104620.277031-5-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

selftest: KVM: Add open sev dev helper

Refactors out open path support from open_kvm_dev_path_or_exit() and
adds new helper for SEV device path.

Signed-off-by: Peter Gonda <pgonda@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: Marc Orr <marcorr@google.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Message-Id: <20211021174303.385706-5-pgonda@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Fix nested SVM tests when built with clang

Though gcc conveniently compiles a simple memset to "rep stos," clang
prefers to call the libc version of memset. If a test is dynamically
linked, the libc memset isn't available in L1 (nor is the PLT or the
GOT, for that matter). Even if the test is statically linked, the libc
memset may choose to use some CPU features, like AVX, which may not be
enabled in L1. Note that __builtin_memset doesn't solve the problem,
because (a) the compiler is free to call memset anyway, and (b)
__builtin_memset may also choose to use features like AVX, which may
not be available in L1.

To avoid a myriad of problems, use an explicit "rep stos" to clear the
VMCB in generic_svm_setup(), which is called both from L0 and L1.

Reported-by: Ricardo Koller <ricarkol@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Fixes: 20ba262f8631a ("selftests: KVM: AMD Nested test infrastructure")
Message-Id: <20210930003649.4026553-1-jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Add helpers to allocate N pages of virtual memory

Add wrappers to allocate 1 and N pages of memory using de facto standard
values as the defaults for minimum virtual address, data memslot, and
page table memslot. Convert all compatible users.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210622200529.3650424-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Add operand to vmsave/vmload/vmrun in svm.c

Building the KVM selftests with LLVM's integrated assembler fails with:

$ CFLAGS=-fintegrated-as make -C tools/testing/selftests/kvm CC=clang
lib/x86_64/svm.c:77:16: error: too few operands for instruction
asm volatile ("vmsave\n\t" : : "a" (vmcb_gpa) : "memory");
^
<inline asm>:1:2: note: instantiated into assembly here
vmsave
^
lib/x86_64/svm.c:134:3: error: too few operands for instruction
"vmload\n\t"
^
<inline asm>:1:2: note: instantiated into assembly here
vmload
^
This is because LLVM IAS does not currently support calling vmsave,
vmload, or vmload without an explicit %rax operand.

Add an explicit operand to vmsave, vmload, and vmrum in svm.c. Fixing
this was suggested by Sean Christopherson.

Tested: building without this error in clang 11. The following patch
(not queued yet) needs to be applied to solve the other remaining error:
"selftests: kvm: remove reassignment of non-absolute variables".

Suggested-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/kvm/X+Df2oQczVBmwEzi@google.com/
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Ricardo Koller <ricarkol@google.com>
Message-Id: <20210210031719.769837-1-ricarkol@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: do not substitute SVM/VMX check with KVM_CAP_NESTED_STATE check

state_test/smm_test use KVM_CAP_NESTED_STATE check as an indicator for
nested VMX/SVM presence and this is incorrect. Check for the required
features dirrectly.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200610135847.754289-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

KVM: selftests: Use consistent message for test skipping

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

selftests: KVM: AMD Nested test infrastructure

Add the basic infrastructure needed to test AMD nested SVM.
This is largely copied from the KVM unit test infrastructure.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>