KVM: selftests: x86: Cache host CPU vendor (AMD vs. Intel)

Cache the host CPU vendor for userspace and share it with guest code.

All the current callers of this_cpu* actually care about host cpu so

KVM: selftests: x86: Cache host CPU vendor (AMD vs. Intel)

Cache the host CPU vendor for userspace and share it with guest code.

All the current callers of this_cpu* actually care about host cpu so
they are updated to check host_cpu_is*.

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
Link: https://lore.kernel.org/r/20230111004445.416840-3-vannapurve@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

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KVM: selftests: x86: Use "this_cpu" prefix for cpu vendor queries

Replace is_intel/amd_cpu helpers with this_cpu_* helpers to better
convey the intent of querying vendor of the current cpu.

Suggest

KVM: selftests: x86: Use "this_cpu" prefix for cpu vendor queries

Replace is_intel/amd_cpu helpers with this_cpu_* helpers to better
convey the intent of querying vendor of the current cpu.

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: David Matlack <dmatlack@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
Link: https://lore.kernel.org/r/20230111004445.416840-2-vannapurve@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

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KVM: selftests: Dedup subtests of fix_hypercall_test

Combine fix_hypercall_test's two subtests into a common routine, the only
difference between the two is whether or not the quirk is disabled.
Pas

KVM: selftests: Dedup subtests of fix_hypercall_test

Combine fix_hypercall_test's two subtests into a common routine, the only
difference between the two is whether or not the quirk is disabled.
Passing a boolean is a little gross, but using an enum to make it super
obvious that the callers are enabling/disabling the quirk seems like
overkill.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Message-Id: <20220928233652.783504-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: selftests: Explicitly verify KVM doesn't patch hypercall if quirk==off

Explicitly verify that KVM doesn't patch in the native hypercall if the
FIX_HYPERCALL_INSN quirk is disabled. The test cu

KVM: selftests: Explicitly verify KVM doesn't patch hypercall if quirk==off

Explicitly verify that KVM doesn't patch in the native hypercall if the
FIX_HYPERCALL_INSN quirk is disabled. The test currently verifies that
a #UD occurred, but doesn't actually verify that no patching occurred.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220928233652.783504-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: selftests: Hardcode VMCALL/VMMCALL opcodes in "fix hypercall" test

Hardcode the VMCALL/VMMCALL opcodes in dedicated arrays instead of
extracting the opcodes from inline asm, and patch in the "o

KVM: selftests: Hardcode VMCALL/VMMCALL opcodes in "fix hypercall" test

Hardcode the VMCALL/VMMCALL opcodes in dedicated arrays instead of
extracting the opcodes from inline asm, and patch in the "other" opcode
so as to preserve the original opcode, i.e. the opcode that the test
executes in the guest.

Preserving the original opcode (by not patching the source), will make
it easier to implement a check that KVM doesn't modify the opcode (the
test currently only verifies that a #UD occurred).

Use INT3 (0xcc) as the placeholder so that the guest will likely die a
horrible death if the test's patching goes awry.

As a bonus, patching from within the test dedups a decent chunk of code.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220928233652.783504-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: selftests: Remove unnecessary register shuffling in fix_hypercall_test

Use input constraints to load RAX and RBX when testing that KVM correctly
does/doesn't patch the "wrong" hypercall. There

KVM: selftests: Remove unnecessary register shuffling in fix_hypercall_test

Use input constraints to load RAX and RBX when testing that KVM correctly
does/doesn't patch the "wrong" hypercall. There's no need to manually
load RAX and RBX, and no reason to clobber them either (KVM is not
supposed to modify anything other than RAX).

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Message-Id: <20220928233652.783504-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: selftests: Compare insn opcodes directly in fix_hypercall_test

Directly compare the expected versus observed hypercall instructions when
verifying that KVM patched in the native hypercall (FIX_

KVM: selftests: Compare insn opcodes directly in fix_hypercall_test

Directly compare the expected versus observed hypercall instructions when
verifying that KVM patched in the native hypercall (FIX_HYPERCALL_INSN
quirk enabled). gcc rightly complains that doing a 4-byte memcpy() with
an "unsigned char" as the source generates an out-of-bounds accesses.

Alternatively, "exp" and "obs" could be declared as 3-byte arrays, but
there's no known reason to copy locally instead of comparing directly.

In function ‘assert_hypercall_insn’,
inlined from ‘guest_main’ at x86_64/fix_hypercall_test.c:91:2:
x86_64/fix_hypercall_test.c:63:9: error: array subscript ‘unsigned int[0]’
is partly outside array bounds of ‘unsigned char[1]’ [-Werror=array-bounds]
63 | memcpy(&exp, exp_insn, sizeof(exp));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
x86_64/fix_hypercall_test.c: In function ‘guest_main’:
x86_64/fix_hypercall_test.c:42:22: note: object ‘vmx_hypercall_insn’ of size 1
42 | extern unsigned char vmx_hypercall_insn;
| ^~~~~~~~~~~~~~~~~~
x86_64/fix_hypercall_test.c:25:22: note: object ‘svm_hypercall_insn’ of size 1
25 | extern unsigned char svm_hypercall_insn;
| ^~~~~~~~~~~~~~~~~~
In function ‘assert_hypercall_insn’,
inlined from ‘guest_main’ at x86_64/fix_hypercall_test.c:91:2:
x86_64/fix_hypercall_test.c:64:9: error: array subscript ‘unsigned int[0]’
is partly outside array bounds of ‘unsigned char[1]’ [-Werror=array-bounds]
64 | memcpy(&obs, obs_insn, sizeof(obs));
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
x86_64/fix_hypercall_test.c: In function ‘guest_main’:
x86_64/fix_hypercall_test.c:25:22: note: object ‘svm_hypercall_insn’ of size 1
25 | extern unsigned char svm_hypercall_insn;
| ^~~~~~~~~~~~~~~~~~
x86_64/fix_hypercall_test.c:42:22: note: object ‘vmx_hypercall_insn’ of size 1
42 | extern unsigned char vmx_hypercall_insn;
| ^~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make: *** [../lib.mk:135: tools/testing/selftests/kvm/x86_64/fix_hypercall_test] Error 1

Fixes: 6c2fa8b20d0c ("selftests: KVM: Test KVM_X86_QUIRK_FIX_HYPERCALL_INSN")
Cc: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Message-Id: <20220928233652.783504-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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KVM: selftests: Fix filename reporting in guest asserts

Fix filename reporting in guest asserts by ensuring the GUEST_ASSERT
macro records __FILE__ and substituting REPORT_GUEST_ASSERT for many
repe

KVM: selftests: Fix filename reporting in guest asserts

Fix filename reporting in guest asserts by ensuring the GUEST_ASSERT
macro records __FILE__ and substituting REPORT_GUEST_ASSERT for many
repetitive calls to TEST_FAIL.

Previously filename was reported by using __FILE__ directly in the
selftest, wrongly assuming it would always be the same as where the
assertion failed.

Signed-off-by: Colton Lewis <coltonlewis@google.com>
Reported-by: Ricardo Koller <ricarkol@google.com>
Fixes: 4e18bccc2e5544f0be28fc1c4e6be47a469d6c60
Link: https://lore.kernel.org/r/20220615193116.806312-5-coltonlewis@google.com
[sean: convert more TEST_FAIL => REPORT_GUEST_ASSERT instances]
Signed-off-by: Sean Christopherson <seanjc@google.com>

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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 pri

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>

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KVM: selftests: Purge vm+vcpu_id == vcpu silliness

Take a vCPU directly instead of a VM+vcpu pair in all vCPU-scoped helpers
and ioctls.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signe

KVM: selftests: Purge vm+vcpu_id == vcpu silliness

Take a vCPU directly instead of a VM+vcpu pair in all vCPU-scoped helpers
and ioctls.

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

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KVM: selftests: Convert fix_hypercall_test away from VCPU_ID

Convert fix_hypercall_test to use vm_create_with_one_vcpu() and pass
around a 'struct kvm_vcpu' object instead of using a global VCPU_ID.

KVM: selftests: Convert fix_hypercall_test away from VCPU_ID

Convert fix_hypercall_test to use vm_create_with_one_vcpu() and pass
around a 'struct kvm_vcpu' object instead of using a global VCPU_ID.

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

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KVM: selftests: Simplify KVM_ENABLE_CAP helper APIs

Rework the KVM_ENABLE_CAP helpers to take the cap and arg0; literally
every current user, and likely every future user, wants to set 0 or 1
argume

KVM: selftests: Simplify KVM_ENABLE_CAP helper APIs

Rework the KVM_ENABLE_CAP helpers to take the cap and arg0; literally
every current user, and likely every future user, wants to set 0 or 1
arguments and nothing else.

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

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selftests: KVM: Test KVM_X86_QUIRK_FIX_HYPERCALL_INSN

Add a test that asserts KVM rewrites guest hypercall instructions to
match the running architecture (VMCALL on VMX, VMMCALL on SVM).
Additionall

selftests: KVM: Test KVM_X86_QUIRK_FIX_HYPERCALL_INSN

Add a test that asserts KVM rewrites guest hypercall instructions to
match the running architecture (VMCALL on VMX, VMMCALL on SVM).
Additionally, test that with the quirk disabled, KVM no longer rewrites
guest instructions and instead injects a #UD.

Signed-off-by: Oliver Upton <oupton@google.com>
Message-Id: <20220316005538.2282772-3-oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

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