APICv traps register writes, so we can't retrieve previous value and omit timer cancelation when mode changes.
timer_mode_mask shouldn't be changing as it depends on cpuid. Signed-off-by: Radim Krčmář <[email protected]> --- #define assign(a, b) (a == b ? false : (a = b, true)) arch/x86/kvm/lapic.c | 12 ++++++++---- arch/x86/kvm/lapic.h | 1 + 2 files changed, 9 insertions(+), 4 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index f538b14..d3a3a1c 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1205,17 +1205,20 @@ static int apic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val) break; - case APIC_LVTT: - if ((kvm_apic_get_reg(apic, APIC_LVTT) & - apic->lapic_timer.timer_mode_mask) != - (val & apic->lapic_timer.timer_mode_mask)) + case APIC_LVTT: { + u32 timer_mode = val & apic->lapic_timer.timer_mode_mask; + + if (apic->lapic_timer.timer_mode != timer_mode) { + apic->lapic_timer.timer_mode = timer_mode; hrtimer_cancel(&apic->lapic_timer.timer); + } if (!kvm_apic_sw_enabled(apic)) val |= APIC_LVT_MASKED; val &= (apic_lvt_mask[0] | apic->lapic_timer.timer_mode_mask); apic_set_reg(apic, APIC_LVTT, val); break; + } case APIC_TMICT: if (apic_lvtt_tscdeadline(apic)) @@ -1449,6 +1452,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu) for (i = 0; i < APIC_LVT_NUM; i++) apic_set_reg(apic, APIC_LVTT + 0x10 * i, APIC_LVT_MASKED); + apic->lapic_timer.timer_mode = 0; apic_set_reg(apic, APIC_LVT0, SET_APIC_DELIVERY_MODE(0, APIC_MODE_EXTINT)); diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h index 5fcc3d3..755a954 100644 --- a/arch/x86/kvm/lapic.h +++ b/arch/x86/kvm/lapic.h @@ -11,6 +11,7 @@ struct kvm_timer { struct hrtimer timer; s64 period; /* unit: ns */ + u32 timer_mode; u32 timer_mode_mask; u64 tscdeadline; atomic_t pending; /* accumulated triggered timers */ -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
