From: Paolo Bonzini Date: Wed, 30 Nov 2022 18:11:47 +0000 (-0500) Subject: KVM: selftests: restore special vmmcall code layout needed by the harness X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=129c48cde6c9e519d033305649665427c6cac494;p=linux.git KVM: selftests: restore special vmmcall code layout needed by the harness Commit 8fda37cf3d41 ("KVM: selftests: Stuff RAX/RCX with 'safe' values in vmmcall()/vmcall()", 2022-11-21) broke the svm_nested_soft_inject_test because it placed a "pop rbp" instruction after vmmcall. While this is correct and mimics what is done in the VMX case, this particular test expects a ud2 instruction right after the vmmcall, so that it can skip over it in the L1 part of the test. Inline a suitably-modified version of vmmcall() to restore the functionality of the test. Fixes: 8fda37cf3d41 ("KVM: selftests: Stuff RAX/RCX with 'safe' values in vmmcall()/vmcall()" Cc: Vitaly Kuznetsov Signed-off-by: Paolo Bonzini Reviewed-by: Sean Christopherson Reviewed-by: Vitaly Kuznetsov Reviewed-by: Maxim Levitsky Message-Id: <20221130181147.9911-1-pbonzini@redhat.com> Signed-off-by: Paolo Bonzini --- diff --git a/tools/testing/selftests/kvm/x86_64/svm_nested_soft_inject_test.c b/tools/testing/selftests/kvm/x86_64/svm_nested_soft_inject_test.c index e497ace629c19..b34980d45648a 100644 --- a/tools/testing/selftests/kvm/x86_64/svm_nested_soft_inject_test.c +++ b/tools/testing/selftests/kvm/x86_64/svm_nested_soft_inject_test.c @@ -41,8 +41,17 @@ static void guest_int_handler(struct ex_regs *regs) static void l2_guest_code_int(void) { GUEST_ASSERT_1(int_fired == 1, int_fired); - vmmcall(); - ud2(); + + /* + * Same as the vmmcall() function, but with a ud2 sneaked after the + * vmmcall. The caller injects an exception with the return address + * increased by 2, so the "pop rbp" must be after the ud2 and we cannot + * use vmmcall() directly. + */ + __asm__ __volatile__("push %%rbp; vmmcall; ud2; pop %%rbp" + : : "a"(0xdeadbeef), "c"(0xbeefdead) + : "rbx", "rdx", "rsi", "rdi", "r8", "r9", + "r10", "r11", "r12", "r13", "r14", "r15"); GUEST_ASSERT_1(bp_fired == 1, bp_fired); hlt();