| Message ID | 20191111123726.93391-1-liran.alon@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | x86: vmx: Verify L2 modification to L1 LAPIC TPR works when L0 use TPR threshold | expand |
On 11/11/19 13:37, Liran Alon wrote: > Test aims to verify that the issue fixed by commit ("KVM: nVMX: Update > vmcs01 TPR_THRESHOLD if L2 changed L1 TPR") is indeed fixed. > > Test performs the following steps: > 1) Disable interrupts. > 2) Raise TPR to high value and queue a pending interrupt in LAPIC by > issueing a self-IPI with lower priority. > 3) Launch guest such that it is provided with passthrough access to > LAPIC. > 4) Inside guest, disable interrupts and lower TPR to 0 and then exit guest. > 5) Back on host, verify that indeed TPR was set to 0 and that enabling > interrupts indeed deliever pending interrupt in LAPIC. > > Without above mentioned commit in L0, step (2) will cause L0 to raise > TPR-threshold to self-IPI vector priority and step (4) will *not* change > vmcs01 TPR-threshold to 0. This will result in infinite loop of VMExits > on TPR_BELOW_THRESHOLD every time L0 attempts to enter L1. Which will > cause test to hang and eventually fail on timeout. > > Reviewed-by: Joao Martins <joao.m.martins@oracle.com> > Signed-off-by: Liran Alon <liran.alon@oracle.com> > --- > x86/unittests.cfg | 9 ++++++++- > x86/vmx_tests.c | 43 +++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 51 insertions(+), 1 deletion(-) > > diff --git a/x86/unittests.cfg b/x86/unittests.cfg > index 5ecb9bba535b..fd3197455aa6 100644 > --- a/x86/unittests.cfg > +++ b/x86/unittests.cfg > @@ -232,7 +232,7 @@ extra_params = -cpu qemu64,+umip > > [vmx] > file = vmx.flat > -extra_params = -cpu host,+vmx -append "-exit_monitor_from_l2_test -ept_access* -vmx_smp* -vmx_vmcs_shadow_test -atomic_switch_overflow_msrs_test -vmx_init_signal_test" > +extra_params = -cpu host,+vmx -append "-exit_monitor_from_l2_test -ept_access* -vmx_smp* -vmx_vmcs_shadow_test -atomic_switch_overflow_msrs_test -vmx_init_signal_test -vmx_apic_passthrough_tpr_threshold_test" > arch = x86_64 > groups = vmx > > @@ -278,6 +278,13 @@ arch = x86_64 > groups = vmx > timeout = 10 > > +[vmx_apic_passthrough_tpr_threshold_test] > +file = vmx.flat > +extra_params = -cpu host,+vmx -m 2048 -append vmx_apic_passthrough_tpr_threshold_test > +arch = x86_64 > +groups = vmx > +timeout = 10 > + > [vmx_vmcs_shadow_test] > file = vmx.flat > extra_params = -cpu host,+vmx -append vmx_vmcs_shadow_test > diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c > index 4aebc3fe1ff9..b137fc5456b8 100644 > --- a/x86/vmx_tests.c > +++ b/x86/vmx_tests.c > @@ -8343,6 +8343,48 @@ static void vmx_apic_passthrough_thread_test(void) > vmx_apic_passthrough(true); > } > > +static void vmx_apic_passthrough_tpr_threshold_guest(void) > +{ > + cli(); > + apic_set_tpr(0); > +} > + > +static bool vmx_apic_passthrough_tpr_threshold_ipi_isr_fired; > +static void vmx_apic_passthrough_tpr_threshold_ipi_isr(isr_regs_t *regs) > +{ > + vmx_apic_passthrough_tpr_threshold_ipi_isr_fired = true; > + eoi(); > +} > + > +static void vmx_apic_passthrough_tpr_threshold_test(void) > +{ > + int ipi_vector = 0xe1; > + > + disable_intercept_for_x2apic_msrs(); > + vmcs_clear_bits(PIN_CONTROLS, PIN_EXTINT); > + > + /* Raise L0 TPR-threshold by queueing vector in LAPIC IRR */ > + cli(); > + apic_set_tpr((ipi_vector >> 4) + 1); > + apic_icr_write(APIC_DEST_SELF | APIC_DEST_PHYSICAL | > + APIC_DM_FIXED | ipi_vector, > + 0); > + > + test_set_guest(vmx_apic_passthrough_tpr_threshold_guest); > + enter_guest(); > + > + report("TPR was zero by guest", apic_get_tpr() == 0); > + > + /* Clean pending self-IPI */ > + vmx_apic_passthrough_tpr_threshold_ipi_isr_fired = false; > + handle_irq(ipi_vector, vmx_apic_passthrough_tpr_threshold_ipi_isr); > + sti(); > + asm volatile ("nop"); > + report("self-IPI fired", vmx_apic_passthrough_tpr_threshold_ipi_isr_fired); > + > + report(__func__, 1); > +} > + > static u64 init_signal_test_exit_reason; > static bool init_signal_test_thread_continued; > > @@ -9022,6 +9064,7 @@ struct vmx_test vmx_tests[] = { > /* APIC pass-through tests */ > TEST(vmx_apic_passthrough_test), > TEST(vmx_apic_passthrough_thread_test), > + TEST(vmx_apic_passthrough_tpr_threshold_test), > TEST(vmx_init_signal_test), > /* VMCS Shadowing tests */ > TEST(vmx_vmcs_shadow_test), > Queued, thanks.
diff --git a/x86/unittests.cfg b/x86/unittests.cfg index 5ecb9bba535b..fd3197455aa6 100644 --- a/x86/unittests.cfg +++ b/x86/unittests.cfg @@ -232,7 +232,7 @@ extra_params = -cpu qemu64,+umip [vmx] file = vmx.flat -extra_params = -cpu host,+vmx -append "-exit_monitor_from_l2_test -ept_access* -vmx_smp* -vmx_vmcs_shadow_test -atomic_switch_overflow_msrs_test -vmx_init_signal_test" +extra_params = -cpu host,+vmx -append "-exit_monitor_from_l2_test -ept_access* -vmx_smp* -vmx_vmcs_shadow_test -atomic_switch_overflow_msrs_test -vmx_init_signal_test -vmx_apic_passthrough_tpr_threshold_test" arch = x86_64 groups = vmx @@ -278,6 +278,13 @@ arch = x86_64 groups = vmx timeout = 10 +[vmx_apic_passthrough_tpr_threshold_test] +file = vmx.flat +extra_params = -cpu host,+vmx -m 2048 -append vmx_apic_passthrough_tpr_threshold_test +arch = x86_64 +groups = vmx +timeout = 10 + [vmx_vmcs_shadow_test] file = vmx.flat extra_params = -cpu host,+vmx -append vmx_vmcs_shadow_test diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c index 4aebc3fe1ff9..b137fc5456b8 100644 --- a/x86/vmx_tests.c +++ b/x86/vmx_tests.c @@ -8343,6 +8343,48 @@ static void vmx_apic_passthrough_thread_test(void) vmx_apic_passthrough(true); } +static void vmx_apic_passthrough_tpr_threshold_guest(void) +{ + cli(); + apic_set_tpr(0); +} + +static bool vmx_apic_passthrough_tpr_threshold_ipi_isr_fired; +static void vmx_apic_passthrough_tpr_threshold_ipi_isr(isr_regs_t *regs) +{ + vmx_apic_passthrough_tpr_threshold_ipi_isr_fired = true; + eoi(); +} + +static void vmx_apic_passthrough_tpr_threshold_test(void) +{ + int ipi_vector = 0xe1; + + disable_intercept_for_x2apic_msrs(); + vmcs_clear_bits(PIN_CONTROLS, PIN_EXTINT); + + /* Raise L0 TPR-threshold by queueing vector in LAPIC IRR */ + cli(); + apic_set_tpr((ipi_vector >> 4) + 1); + apic_icr_write(APIC_DEST_SELF | APIC_DEST_PHYSICAL | + APIC_DM_FIXED | ipi_vector, + 0); + + test_set_guest(vmx_apic_passthrough_tpr_threshold_guest); + enter_guest(); + + report("TPR was zero by guest", apic_get_tpr() == 0); + + /* Clean pending self-IPI */ + vmx_apic_passthrough_tpr_threshold_ipi_isr_fired = false; + handle_irq(ipi_vector, vmx_apic_passthrough_tpr_threshold_ipi_isr); + sti(); + asm volatile ("nop"); + report("self-IPI fired", vmx_apic_passthrough_tpr_threshold_ipi_isr_fired); + + report(__func__, 1); +} + static u64 init_signal_test_exit_reason; static bool init_signal_test_thread_continued; @@ -9022,6 +9064,7 @@ struct vmx_test vmx_tests[] = { /* APIC pass-through tests */ TEST(vmx_apic_passthrough_test), TEST(vmx_apic_passthrough_thread_test), + TEST(vmx_apic_passthrough_tpr_threshold_test), TEST(vmx_init_signal_test), /* VMCS Shadowing tests */ TEST(vmx_vmcs_shadow_test),
Test aims to verify that the issue fixed by commit ("KVM: nVMX: Update vmcs01 TPR_THRESHOLD if L2 changed L1 TPR") is indeed fixed. Test performs the following steps: 1) Disable interrupts. 2) Raise TPR to high value and queue a pending interrupt in LAPIC by issueing a self-IPI with lower priority. 3) Launch guest such that it is provided with passthrough access to LAPIC. 4) Inside guest, disable interrupts and lower TPR to 0 and then exit guest. 5) Back on host, verify that indeed TPR was set to 0 and that enabling interrupts indeed deliever pending interrupt in LAPIC. Without above mentioned commit in L0, step (2) will cause L0 to raise TPR-threshold to self-IPI vector priority and step (4) will *not* change vmcs01 TPR-threshold to 0. This will result in infinite loop of VMExits on TPR_BELOW_THRESHOLD every time L0 attempts to enter L1. Which will cause test to hang and eventually fail on timeout. Reviewed-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: Liran Alon <liran.alon@oracle.com> --- x86/unittests.cfg | 9 ++++++++- x86/vmx_tests.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 51 insertions(+), 1 deletion(-)