Initialize the IDT and exception handlers for all non-barebones VMs and
vCPUs on x86. Forcing tests to manually configure the IDT just to save
8KiB of memory is a terrible tradeoff, and also leads to weird tests
(multiple tests have deliberately relied on shutdown to indicate success),
and hard-to-debug failures, e.g. instead of a precise unexpected exception
failure, tests see only shutdown.
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Link: https://lore.kernel.org/r/20240314232637.2538648-11-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
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>
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>
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>
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>
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: 6c2fa8b20d ("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>
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: 4e18bccc2e
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>
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>
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>
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>
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>
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>
