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charset="utf-8" Content-Transfer-Encoding: quoted-printable On Wed, Aug 26, 2026, Yosry Ahmed wrote: > On Wed, Aug 26, 2026 at 4:39=E2=80=AFPM Sean Christopherson wrote: > > diff --git a/tools/testing/selftests/kvm/x86/aperfmperf_test.c b/tools/= testing/selftests/kvm/x86/aperfmperf_test.c > > index 11f5894d8ac7..a082658c1e48 100644 > > --- a/tools/testing/selftests/kvm/x86/aperfmperf_test.c > > +++ b/tools/testing/selftests/kvm/x86/aperfmperf_test.c > > @@ -83,7 +83,7 @@ static void l1_vmx_code(struct vmx_pages *vmx) > > vmreadz(CPU_BASED_VM_EXEC_CONTROL) | CPU_BASED_USE_MSR_= BITMAPS); > > > > GUEST_ASSERT(!vmwrite(GUEST_RIP, (u64)l2_guest_code)); >=20 > Do we wanna give the same treatment to vmwrite()? Yes, and vmreadz(). Assuming '0' is simultaneously a reasonable failure an= d "safe" value is so stupid, especially since AFAICT literally none of the users act= ually need to gracefully tolerate failure. LOL, and it can't possibly work, because vmread() clobbers the zeroed value= on VM-Fail. Hilarious. I didn't include those changes purely because I had "#$*@ this code" fatigu= e. :-) But since this is going to conflict the world over, yeah, it makes sense to= just fix everything. > > - GUEST_ASSERT(!vmlaunch()); > > + vmlaunch(); > > } > > > > static void guest_code(void *nested_test_data) > [..] > > diff --git a/tools/testing/selftests/kvm/x86/nested_emulation_test.c b/= tools/testing/selftests/kvm/x86/nested_emulation_test.c > > index 2b38eff4f516..11fe4a31eda0 100644 > > --- a/tools/testing/selftests/kvm/x86/nested_emulation_test.c > > +++ b/tools/testing/selftests/kvm/x86/nested_emulation_test.c > > @@ -102,7 +102,7 @@ static void guest_code(void *test_data) > > exit_insn_len =3D vmcb->control.next_rip - vmcb= ->save.rip; > > GUEST_ASSERT_EQ(vmcb->save.rip, (u64)l2_instruc= tion); > > } else { > > - GUEST_ASSERT_EQ(i ? vmresume() : vmlaunch(), 0)= ; > > + i ? vmresume() : vmlaunch(); >=20 > Ewww >=20 > > exit_reason =3D vmreadz(VM_EXIT_REASON); > > exit_insn_len =3D vmreadz(VM_EXIT_INSTRUCTION_L= EN); > > GUEST_ASSERT_EQ(vmreadz(GUEST_RIP), (u64)l2_ins= truction); > > diff --git a/tools/testing/selftests/kvm/x86/nested_exceptions_test.c b= /tools/testing/selftests/kvm/x86/nested_exceptions_test.c > > index 50c271a03692..c36c11b5f518 100644 > > --- a/tools/testing/selftests/kvm/x86/nested_exceptions_test.c > > +++ b/tools/testing/selftests/kvm/x86/nested_exceptions_test.c > > @@ -112,7 +112,7 @@ static void vmx_run_l2(void *l2_code, int vector, u= 32 error_code) > > { > > GUEST_ASSERT(!vmwrite(GUEST_RIP, (u64)l2_code)); > > > > - GUEST_ASSERT_EQ(vector =3D=3D SS_VECTOR ? vmlaunch() : vmresume= (), 0); > > + vector =3D=3D SS_VECTOR ? vmlaunch() : vmresume(); >=20 > Ewwwww >=20 > Can we make these if/else statements? It was already ugly, but it > looks even more ugly outside of GUEST_ASSERT_EQ(). Yeah. Another idea would be: void vmenter(bool do_vmlaunch) { if (do_vmlaunch) vmlaunch(); else vmresume(); } To yield: vmenter(vector =3D=3D SS_VECTOR); vmenter(!i); Never mind, that's a terrible idea, the call sites are inscrutable.