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    Subject[PATCH 5.16 178/200] KVM: selftests: Dont skip L2s VMCALL in SMM test for SVM guest
    Date
    From: Sean Christopherson <seanjc@google.com>

    [ Upstream commit 4cf3d3ebe8794c449af3e0e8c1d790c97e461d20 ]

    Don't skip the vmcall() in l2_guest_code() prior to re-entering L2, doing
    so will result in L2 running to completion, popping '0' off the stack for
    RET, jumping to address '0', and ultimately dying with a triple fault
    shutdown.

    It's not at all obvious why the test re-enters L2 and re-executes VMCALL,
    but presumably it serves a purpose. The VMX path doesn't skip vmcall(),
    and the test can't possibly have passed on SVM, so just do what VMX does.

    Fixes: d951b2210c1a ("KVM: selftests: smm_test: Test SMM enter from L2")
    Cc: Maxim Levitsky <mlevitsk@redhat.com>
    Signed-off-by: Sean Christopherson <seanjc@google.com>
    Message-Id: <20220125221725.2101126-1-seanjc@google.com>
    Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
    Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    tools/testing/selftests/kvm/x86_64/smm_test.c | 1 -
    1 file changed, 1 deletion(-)

    diff --git a/tools/testing/selftests/kvm/x86_64/smm_test.c b/tools/testing/selftests/kvm/x86_64/smm_test.c
    index d0fe2fdce58c4..db2a17559c3d5 100644
    --- a/tools/testing/selftests/kvm/x86_64/smm_test.c
    +++ b/tools/testing/selftests/kvm/x86_64/smm_test.c
    @@ -105,7 +105,6 @@ static void guest_code(void *arg)

    if (cpu_has_svm()) {
    run_guest(svm->vmcb, svm->vmcb_gpa);
    - svm->vmcb->save.rip += 3;
    run_guest(svm->vmcb, svm->vmcb_gpa);
    } else {
    vmlaunch();
    --
    2.34.1


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